Forum: Frontier BBS

HVYRAIN: Excessive Rainfall Discussion

From COD Weather Processor@1:2320/127 to wx-storm@lists.illinois.edu on Tue Jul 7 00:48:54 2026

FOUS30 KWBC 070048
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
848 PM EDT Mon Jul 6 2026

Day 1
Valid 01Z Tue Jul 07 2026 - 12Z Tue Jul 07 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE MID ATLANTIC AND SOUTHERN NEW ENGLAND...

...Mid Atlantic to Southern New England...

PWAT anomalies maintain +2 to +3 deviations as we move through the
evening across much of the Mid Atlantic and Northeast. Latest
mesoanalysis indicates 2.0-2.4" PWAT relevant across much of VA/NC
and points northeast along and east of I=3D95. Present pattern
indicates the best instability, however, will reside over VA/NC up
through the western half of PA with its orientation driven by the
residence of a quasi-stationary front over the area. Scattered
thunderstorms are already causing issues across western PA down
into WV and VA given the environment in place with the threat
likely to continue for several more hours before dissipation. The
activity across central and southeastern VA will likely maintain a
presence beyond 06z before finally dwindling, but even still some
cells could linger well into the early morning hours Tuesday. Low
FFG's across many areas in the Mid Atlantic precluded the activity
in question, so the threat for flash flooding remains more elevated
than normal. For more on the threat across western PA down into the
Central Mid Atlantic, please see MPD #0632. For more information on
the current threat into VA, see MPD #0630. Given the above, the
SLGT risk over western PA down through the Central and Southern Mid
Atlantic remains with a high- end SLGT forecast for that area of
western PA between I-80 down to the M/D.

For the Northeast, surface low will wander off the northern Mid
Atlantic coast with some onshore component likely to materialize
over parts of Southern New England. The issue in sustaining a more
appreciable threat for flash flooding is the lack of general
instability with the area theta_E pattern relatively benign for
areas inland, away from the coastal plain. Increasing low-level
convergence will transpire over Southern New England which could
produce some low-topped convection capable of locally heavy
rainfall given the antecedent environment. In this case, this was
enough to maintain the SLGT risk over the above areas, but not
enough of a risk to maintain the previous Moderate risk, so that
was removed with coordination from the local WFO's.

...Upper Midwest...

Energetic shortwave rolling through southern Canada extends into
the northern tier of the CONUS with thunderstorms migrating
southeast through the North Woods of MN. Expectation is for the
convection to be heavy enough to potentially cause some isolated
flash flood concerns, but likely too progressive to cause more
significant problems. Will monitor the southwestern edge of the
convective signature for possible training as indicated via a few
of the CAMs this afternoon/evening, but for now, the MRGL risk was
more than relevant for this setup.

...Texas into Tennessee Valley...

A few disturbances will interact with a generally favorable
environment in place to allow for an isolated flash flood threat
from the central RGV all the way back into the Tennessee Valley.
A few more organized complexes are moving through the Lower
Mississippi Valley currently which will be the root of any flash
flood concerns in that area for the next several hours. MRGL risk
remains in these areas for the limited threat overnight.

Kleebauer
=20

Day 2
Valid 12Z Tue Jul 07 2026 - 12Z Wed Jul 08 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE NORTHERN PLAINS AND MID-ATLANTIC...

20z Update: A Slight risk was added across portions of the Mid-
Atlantic where cell mergers near a backdoor front should lead to
isolated to scattered flash flooding. Pretty good agreement between
the 12z HREF and REFS on this axis from portions of southwest PA
into central VA and northeast NC, with rainfall expected to
locally exceed 3".

The Marginal risk was expanded across the TN Valley and into
portions of the lower MS Valley. Convection along this corridor
should be disorganized and pulse in nature...however lingering
high moisture and instability will support heavy rainfall rates
and a localized flash flood risk where cell mergers occur.

The Slight risk across portions of the Dakotas into MN still looks in
good shape, and so only minor adjustments were made.

Chenard

...Previous Discussion...

...Northern Plains...

During this period a shortwave rounding the ridge anchored over the
Four Corners will make its way through central Montana to western
Minnesota. This shortwave will drive downstream PVA and height
falls while concurrent but modest RRQ diffluence in the tail of a
distant jet streak helps enhance synoptic lift. At the surface, a
wavering boundary with a wave of low pressure moving along it will
try to shift north in response to subtly increasing southerly low-
level flow, with the resulting isentropic ascent aiding lift across
the region. This robust ascent will act upon PWs that will surge
to 1.25 to 1.75 inches, or around +2 sigma, collocated with a plume
of MUCAPE exceeding 2000 J/kg.

Areal coverage of convection will increase through the day,
tracking from west to east. The environment will be favorable for
backbuilding or training. Hourly rainfall as much as 0.75"-1.0"+
is likely, which could create locally 2-3" of rainfall as reflected
by modest (5-15% chance) of 3"/24 hrs. Soils across this part of
the country have been recently wet thus increasing sensitivity. A
Slight Risk remains in effect from the eastern Dakotas to western
Wisconsin. A broad Marginal Risk extends from eastern Montana to
north-central Wisconsin.

...Mid-Atlantic States...

Much of this region will continue to have scattered to widespread
thunderstorms as weak impulses traverse through the trough
overhead. In general, these storms should be of the pulse variety
and move E/NE on 15 kts of 0-6km mean wind. However, the impressive thermodynamics in place (PWs over 1.75 inches overlapping MUCAPE
of 1000-2000 J/kg) will support rainfall rates of 1-2"/hr, through
which any short-term training or repeating rounds could lead to
instances of flash flooding.

...Eastern Massachusetts & Rhode Island...

A wave of low pressure will be tracking south of Rhode Island
during this period keeping some showers and thunderstorms in place
across southern New England. Although new accumulations are
expected to be modest hourly rates of 1+ inches/hr will be
possible. A Marginal Risk area was maintained for this period.

Weiss/Campbell
=20

Day 3
Valid 12Z Wed Jul 08 2026 - 12Z Thu Jul 09 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE UPPER MISSISSIPPI VALLEY/UPPER GREAT LAKES...

The Slight risk over the Upper Midwest still look pretty good,
although we did nudge it a bit south with this update. Convection
should be ongoing at 12z Wednesday moving from west to east across
MN and WI. While this activity could be moving along and weakening
during the morning, we should see renewed development along the
front by afternoon from southeast MN into WI. Approaching shortwave
energy and an upper level jet will help drive this uptick in
activity, with PWs above the climatological 90th percentile and
CAPE approaching 2000 J/kg supporting heavy rainfall rates. While a
progressive squall line should eventually evolve, there will be an
opportunity for some training and backbuilding during the
development and initial upscale growth phase of convection.
Rainfall totals of 1-2" should be most common, but localized swaths
over 3" are probable and supported by the 12z RRFS.

A Marginal risk was added across portions of the OH/TN Valley into
the Mid-Atlantic. A shortwave moving across KY/TN and a lingering
backdoor front over WV/VA should both act as a focus for
convective development Wednesday. Not expecting anything too
organized or widespread, but enough moisture and instability will
be around to support locally heavy rainfall rates.

Chenard
=20

Day 4 and Day 5

Valid 12Z Thu Jul 09 2026 - 12Z Sat Jul 11 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE OHIO VALLEY AND CENTRAL APPALACHIANS ON DAY 5...

20Z Update: Additional information provided on an upgrade for the
D5 period with a maintenance of a broad MRGL for D4, below.

Stronger flow will initially remain along the northern tier of the
CONUS early to mid-week with mean upper-ridging across the western
to central U.S. Embedded shortwaves rounding the upper-ridge will
eventually lead to deepening troughing across the the Midwest and
adjacent areas on Thursday. The southward shift of stronger flow
aloft into the central Plains east through the Middle Mississippi/Ohio/Tennessee Valleys and Lower Great Lakes will bring
more scattered thunderstorm chances across the region.

Seasonably high instability and moisture pooling along a southward
progressing, wavy cold front will support locally heavy rainfall
bringing the threat for at least isolated instances of flash
flooding, and a broad Marginal Risk of Excessive Rainfall exists
for D4 (Thursday) with enough confidence to upgrade a large portion
of the Ohio Valley and Central Appalachians to a SLGT risk for D5
(Friday) as increasing low-level convergence ample mid-level ascent
will likely trigger widespread convection with training potential
over the region, compounding with any impacts from convection the
previous forecast period. Consensus grew over the past series of
NWP updates with the ensemble mean QPF structure signaling a large
area of 1-2" areal average totals with embedded higher amounts
positioned over the southern-third of IL/IN/OH through much of KY
into WV. This is coincident with the progression of both the front
and a strengthening shortwave trough migrating out of the Central
Plains into the region as we move into Friday. ML output is also
favoring the Ohio River Basin into the Central Appalachians
extended from southwestern PA down through WV as terrain influences
along with the synoptic evolution will couple into a targeted
threat for heavy rainfall and local maxima sufficient for scattered
flash flood prospects. PQPF forecast for at least 1" signals a
broad 20-40% probability with a bullseye of 50-80% located over the
Central Appalachian front in northern WV. This is a relatively
bullish signature at this lead, enough to warrant an upgrade to a
SLGT risk over the aforementioned areas from IL to WV.

Putnam/Kleebauer
=20

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!83QLPwS03x0ZQX4qf8Ktj6HjV1TkvOHYv-FlwSD5nnfG= 7_gBPTOBd-O8oC__TrzOFabeo1rvRz-QU_4vrYyMa7nhY-0$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!83QLPwS03x0ZQX4qf8Ktj6HjV1TkvOHYv-FlwSD5nnfG= 7_gBPTOBd-O8oC__TrzOFabeo1rvRz-QU_4vrYyMC8-Ln90$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!83QLPwS03x0ZQX4qf8Ktj6HjV1TkvOHYv-FlwSD5nnfG= 7_gBPTOBd-O8oC__TrzOFabeo1rvRz-QU_4vrYyMbwzyHzM$=20

$$

=3D =3D =3D
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* Origin: Capitol City Weather Station (1:2320/127)

From COD Weather Processor @1:2320/107 to All on Wed Jul 8 00:50:26 2026

FOUS30 KWBC 080050
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
850 PM EDT Tue Jul 7 2026

Day 1
Valid 01Z Wed Jul 08 2026 - 12Z Wed Jul 08 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE NORTHERN PLAINS, UPPER MIDWEST AND SOUTHERN MID-ATLANTIC...

...Mid Atlantic...

Elevated PWATs above 2" and the presence of a cold front across
southern and southeast VA has led to a focus of enhanced convection
across the area. Significant hourly rates are the driver behind any
flash flood prospect as weak shear coupled with modest buoyancy
allows for pulse type convection with slow cell motions. Outflows
generated by storms have allowed for local initiation of
thunderstorms considering how favorable the environment is across
the region. This setup is also conducive for heavy rain prospects
all the day into NC where current radar/sat composite indicate a
strong cluster of thunderstorms already impacting the Raleigh
metro. This will continue for another few hours before the loss of
diurnal instability will eventually degrade any activity in the
area. This goes for areas of VA as well, so the SLGT risk was
maintained in these areas with the best prospect for flash flooding
likely to occur in the window between 00-06z. The SLGT risk was
expanded to include the Raleigh metro due to the ongoing heavy
rainfall and flash flood warnings in effect with potential impacts
lingering for another few hours.

...Northern Plains to Upper Midwest...

Energetic shortwave analyzed upstream over eastern MT into the
western Dakotas will aid in the maturation of a round of strong to
severe thunderstorms across eastern ND/SD, extending through MN
with activity eventually propagating east and southeast into WI
overnight. CAMs have been consistent with the signature of this
convective initiation along a front draped over the region.
Increased convergence along the front will stem from a combination
of frontal enhancement and the nose of an 850mb LLJ entering into
the area. Flow aloft will align parallel to the front with shear
provided via a 50kt jet max at 500mb. Deep moisture pool across the
Northern Plains and Midwest is present with PWATs between
1.7-2.0", verified via the 00z KMPX sounding running at 1.93"
PWATs as of the 08/00z RAOB. HREF probs continue to highlight
central MN as the focal point, however, hourly CAMs such as the
HRRR have inferred that the area over northeast SD down through
south-central MN may end up as the primary target, or at least
provide a secondary maxima as they align within the quasi-
stationary front in place, and storm motions move into the warm
sector and better localized shear overnight. No matter the case,
the environment is ripe for locally enhanced rainfall with hourly
rates likely to reach 2-3"/hr in the strongest cell cores leading
to rainfall totals between 3-5" in spots across the region. More on
this setup can be reviewed with the latest MPD #0642 issued over
the area of interest. The previous SLGT risk was generally
maintained with just a minor expansion to the east in WI, and a
nudge south on the southern flank of the inherited risk.

Kleebauer

Day 2
Valid 12Z Wed Jul 08 2026 - 12Z Thu Jul 09 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE UPPER MISSISSIPPI VALLEY/UPPER GREAT LAKES...

20Z Update...
The previously issued outlook still in good shape. Even though
there were a couple of minor adjustments...there was no fundamental
shift in the forecast reasoning.

Previous Excessive Rainfall Discussion...

...Central Plains to the Upper Great Lakes...

Several locations remain sensitive given recent rains and lowered
FFGs, particularly for portions of the Upper Mississippi Valley and
Upper Great Lakes. A Slight Risk area remains warranted for this
part of the country where areal averages of 1-2 inches are expected
with localized swaths of 3+ inches. Convection from overnight may
be weakening during the morning hours however redevelopment near
the frontal boundary midday should occur over Minnesota and
Wisconsin. Approaching shortwave energy and an upper level jet
will help drive this uptick in activity, with PWs above the
climatological 90th percentile and CAPE approaching 2000 J/kg
supporting heavy rainfall rates. While a progressive squall line
should eventually evolve, there will be an opportunity for some
training and backbuilding during the development and initial
upscale growth phase of convection. A Marginal Risk spans from the
Central Plains to the Great Lakes and surrounding area.

...Tennessee/Ohio Valley to the Mid-Atlantic...

A Marginal Risk was maintained for this region. A shortwave moving
across Kentucky/Tennessee and a lingering backdoor front over
West Virginia/Virginia should both act as a focus for convective
development. Not expecting anything too organized or widespread,
but enough moisture and instability will be around to support
locally heavy rainfall rates.

Campbell

Day 3
Valid 12Z Thu Jul 09 2026 - 12Z Fri Jul 10 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE NORTHERN/CENTRAL PLAINS, MIDWEST, OHIO/TENNESSEE VALLEYS
AND GREAT LAKES REGION...

Stronger flow will initially remain along the northern tier of the
CONUS early to mid-week with mean upper-ridging across the western
to central United States. Embedded shortwaves rounding the upper-
ridge will eventually lead to deepening troughing across the the
Midwest and adjacent areas on Thursday. The southward shift of
stronger flow aloft into the Central Plains east through the Middle Mississippi/Ohio/Tennessee Valleys and Lower Great Lakes will
bring a better chance for scattered thunderstorms across the
region.

Seasonably high instability and moisture pooling southward of a wavy
cold front will support locally heavy rainfall rates with training
potential over the region. That will compound impacts from
convection the previous forecast period. A large area of 1-2 inch areal
average totals with embedded higher amounts positioned over the
southern-third of Illinois/Indiana/Ohio through much of Kentucky
into West Virginia. This is coincident with the progression of both
the front and a strengthening shortwave trough migrating out of
the Central Plains into the region as we move into Friday. Machine
Learning output is also favoring the Ohio River Basin into the
Central Appalachians extended from southwestern Pennsylvania down
through West Virginia as terrain influences along with the synoptic
evolution will couple into a targeted threat for heavy rainfall
and local maxima sufficient for scattered flash flood prospects.

Bann

Day 4 and Day 5

Valid 12Z Fri Jul 10 2026 - 12Z Sun Jul 12 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE OHIO/MID-MISSISSIPPI VALLEYS AND CENTRAL APPALACHIANS ON
FRIDAY AND SATURDAY...

...Ohio and Mid-Mississippi Valley's...

20Z Update: The previous forecast was generally maintained with the
overall synoptic pattern still maintaining continuity in the
proposed evolution at both the upper levels and at the surface.
Ensembles continue to indicate a multi-day bout of heavy rainfall
across the Mid-Mississippi to Ohio Valley in conjunction with both
mid-level ascent and the proxy of a cold/quasi-stationary front
that will aid in scattered to widespread convective activity in-of
a very moist environment positioned over the region. The trends in
guidance indicate a bit more emphasis further west into MO with
even the D4 showing an extension of heavy rain prospects back into
the Southern High Plains thanks to a likely convective complex
developing around the eastern flank of a strengthening ridge over
the Four Corners. Classic summer pattern materializing for areas
west of the Mississippi, so the threat for isolated flash flooding
will likely have some footing in the extended with D4 the first
prospectus day for the threat. The SLGT risk inherited was expanded
into the Mid-Mississippi area of eastern MO on D4 and across
southern MO on D5 given the trends. The MRGL risk expands westward
into the Southern High Plains on D4.

Kleebauer

..Previous Discussion..

Stronger flow will initially remain along the northern tier of the
CONUS through mid-week with mean upper-ridging across the western
to central U.S. Embedded shortwaves rounding the upper-ridge will
eventually lead to deepening troughing across the the Midwest and
adjacent areas by Thursday. The southward shift of stronger flow
aloft will bring increasingly widespread storm chances from the
central Plains east through the Mississippi Valley into the
Ohio/Tennessee Valleys and central Appalachians. Seasonably high
instability and moisture pooling along a southward progressing,
wavy cold front will lead to multiple rounds of heavy rain-
producing storms later this week and into the weekend. Mean flow
generally parallel to the east-west oriented front will support clustering/training storms increasing the threat for longer-
duration rainfall and higher totals. The embedded waves will help
to slow the frontal progression at times also helping to increase
the chance for repeated rounds/training of storms. For Friday (day
4), the latest guidance shows widespread areal average rainfall of
1-2" with good overlap between the ensemble means and AI guidance
favoring the Ohio/Tennessee Valleys into the central Appalachians,
where a Slight Risk has been maintained. While the guidance is not
quite as bullish on amounts yet on Saturday (day 5), a similar set
up will support additional locally heavy rainfall, with the concern
being that much of the mean/AI guidance overlaps similar regions
to Friday, favoring the middle to upper Ohio/Tennessee Valleys into
the central Appalachians. Given the increasingly wet antecedent
conditions expected from the prior days with additional storms
likely, another Slight Risk has been introduced.

Putnam

...Southwest U.S...

Monsoonal activity will finally make an appearance by the end of
the week with the threat ramping up into some more appreciable in
regards to magnitude and coverage across the terrain of
southeastern and central AZ, mainly following the Huachucas up
through the Mogollon Rim in east-central AZ. PWATs will surge north
along prevailing southerly flow on the western side of the broad
upper ridge centered over the Four Corners. QPF signatures are
textbook in monsoonal convection billowing up across the terrain at
lead which is a good indicator of at least the isolated threat of
flash flooding to kick off the Monsoon season across the Southwest.
A MRGL risk has been added to account for the threat on D5 with
perhaps an upgrade plausible on D4, but signals are not as prolific
on Friday compared to Saturday on both the global deterministic and
their ensembles.

Kleebauer

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!_rYHCi7yHcS4gRo8rsva7ZNeNKx8BQt46w9cZasdyuC3qis9oZiZ1lRJx_6FCbCFcuxbllg3SthNmP8DJEmVEfGDk5U$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!_rYHCi7yHcS4gRo8rsva7ZNeNKx8BQt46w9cZasdyuC3qis9oZiZ1lRJx_6FCbCFcuxbllg3SthNmP8DJEmVWNoCbYQ$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!_rYHCi7yHcS4gRo8rsva7ZNeNKx8BQt46w9cZasdyuC3qis9oZiZ1lRJx_6FCbCFcuxbllg3SthNmP8DJEmV-qVjtFA$

$$

= = =
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--- scorpsmtpd
* Origin: Capitol City Online (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Jul 11 20:05:32 2026

FOUS30 KWBC 112005
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
405 PM EDT Sat Jul 11 2026

Day 1
Valid 16Z Sat Jul 11 2026 - 12Z Sun Jul 12 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
ARIZONA AND THE SOUTHERN PLAINS TO THE CENTRAL APPALACHIANS...

1600Z Update -- Main change to the Day 1 ERO was to expand the
Marginal Risk to include much of the western and central Gulf
Coast. Deep-layer bulk shear values do remain low (<20kts), however
weak mid-level perturbations (including a H5 vort across South TX)
and weak, broad cyclonic flow along the coast will allow for more
organized storm clusters within such a favorable thermodynamic
profile (mixed layer CAPEs between 2000-3000 J/Kg and PWs of
2.0-2.3 inches).

Hurley

Previous discussion...

...OK into the OH and TN valleys...
An active convective regime is anticipated ahead of a
southeastward moving shortwave trough axis extending from MO to OH.
At 12z this morning, an initial round of convection will be
ongoing from southern IL into portions of KY and TN. Model guidance
supports a transition toward a primarily forward propagating
convective mode this morning, which should place the overall flash
flood risk on a declining trend, though localized upwind
propagation may keep an isolated threat going.

By this afternoon, the primary MCV/shortwave will shift over IL
and IN, interacting with a southward moving frontal boundary to
trigger scattered redevelopment across portions of IL, IN and WV.
Within this zone, PW values near or just under 2" will overlap with
CAPE of 1000-2000 J/kg. While widespread convective organization
is not anticipated, slow cell motions and localized mergers near
the frontal zone will support heavy rainfall rates capable of
producing localized pockets of 2-3" of rain. This is supported by
the 00z HREF and REFS, which both show FFG exceedance
probabilities of 15-40%.

A more organized, and potentially higher end, flash flood threat
is expected to evolve later this afternoon into tonight across
portions of KY and TN. Convection should develop to the south-
southeast of the main shortwave/MCV, likely focusing along remnant
outflow boundaries and instability gradients left behind by the
morning activity. Global deterministic and AI models favor a heavy
rainfall axis focused primarily from KY into northeast TN,
whereas high res models (including the RRFS/REFS) suggest the core
threat may track further south into TN. Given the strong westerly
low level moisture transport south of the MCV, the environment
will be favorable for backbuilding and training convective clusters
tonight. This environment, combined with PWs hovering around 2",
suggests that many HREF members may be underdoing the
afternoon/nocturnal threat. Do expect to see a swath of heavy
rainfall materialize somewhere across the KY/TN corridor, where an
axis of locally higher end flash flood impacts is possible. A
higher end Slight risk is maintained, with a MDT risk upgrade not
out of the question if we gain spatial model convergence and more
confidence on exact convective mode.

Further west, isolated to scattered flash flooding is also expected
across portions of central OK into AR. Low level flow will become
convergent on the southwestern flank of the broader convective
regime. Slow cell motions near a boundary will pose a threat over
OK, while enhanced northerly flow on the western periphery of the
MCV/shortwave will converge with the broad south-southwesterly
inflow to promote some backbuilding/training threat over parts AR.

...Mid-Atlantic...
A localized flash flood threat is forecast across portions of the
Mid-Atlantic. While low level flow will be northerly, one or two
low level convergence axes are projected to setup across the
region, potentially acting as a focus for convection. Despite the
northerly flow, ample moisture and instability will remain in
place. Convective cells will generally track from north to south,
but localized repeating cells will be possible along the trough
axis. The strongest signal for localized 3" totals with the HREF
resides along the coastal plain from NJ southward into southeast
VA where convergence is enhanced. Because FFG values are generally
higher here compared to inland locations, think the overall flash
flood risk should stay isolated, though localized urban and low
lying flood impacts are expected.

...AZ and NM...
The persistent terrain driven pattern continues across the
Southwest, with convection developing over the higher elevations
before propagating southwestward into a pooling instability axis
over the lower deserts of southern AZ. Instability and moisture
profiles should be a bit higher today relative to the past few
days, leading to a corresponding increase in the overall flash
flood risk. Both the 00z HREF and REFS depict greater convective
coverage and higher localized rainfall totals. While fast
southwestward storm propagation and cell speeds may act as a
limiting factor, the moisture/instability footprint should be
sufficient to promote some cell mergers and localized 1-2"/hr
rainfall, justifying the maintenance of the Slight risk.

A Marginal risk has been added to portions of eastern NM. This area
received locally heavy rain yesterday, and the model QPF signal is
a bit stronger today within an environment characterized by
slightly higher moisture and instability. Convection should remain
isolated to scattered, with the primary flash flood threat focused
over recent burn scars, particularly across the Sacramento
Mountains.

...TX...
A Marginal risk was added to portions of the TX Hill Country, where
PWs are forecast to climb above 2". Isolated to scattered
convection is expected within a broad southerly low level flow
regime. While most cells will remain transient and produce only
brief downpours, any cells that establish mesoscale organization
could briefly train or backbuild into the low level inflow.
Guidance suggests a weak MCV currently south of the Rio Grande
that may track northward towards the region later today, which
could provide an additional focus for ascent. The risk area aligns
closely with the HREF and REFS 1" EAS probabilities of 10-20%
(signaling organization potential), and 3" neighborhood
probabilities exceeding 40%. Global deterministic and AI suites
also show a distinct convective focus over this corridor.

Chenard

Day 2
Valid 12Z Sun Jul 12 2026 - 12Z Mon Jul 13 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM PORTIONS OF
EASTERN KENTUCKY AND TENNESSEE INTO THE CAROLINAS..

2000Z Update: Only minor tweaks made to the Day 2 ERO based on the
latest (12Z) guidance suite. We did trim back a little bit of the
Marginal Risk across central AR, northern MS, and along the OH
River based on the latest trends. Especially with the CAMs,
including the HREF probabilistic suite, which collectively
indicate more pronounced post-MCV stability and drying over these
areas.

Otherwise, one area we will need to continue to monitor the need
for a Slight Risk on the current Day 2 period will be the central
Gulf Coast, specifically southern LA. Both the 12Z HREF and REFS
have >5" 24hr probabilities above 50% across the southern LA Gulf
Coast. This ahead (south) of an elongated H5 vort lobe and
associated W-E surface front that will be pressing south towards
the Gulf Coast. Thermodynamically, the airmass will remain primed
for areas of excessive rainfall, with mixed layer CAPEs between
1500-2500 J/Kg and PWs 2.1-2.3" remaining optimal in terms of
rainfall efficiency. However, working against an upgrade for a
slight would be the extensive swamps/marshes within this region,
along with 0-6km bulk shear values remaining under 20kts,
indicative of intense sub-hourly rainfall rates that should quickly
become outflow dominated. For now we've continued with the Marginal
Risk.

Hurley

Previous discussion..

...Southeast Quarter of the Country...
A Slight risk has been introduced stretching from KY and TN
eastward into southern VA and the Carolinas. A well defined
shortwave/low over the KY/TN vicinity will interact with a slow
moving backdoor front to focus organized convection. High res
guidance, including the RRFS, FV3 and 3km NAM, indicates a
concentrated axis of convection capable of producing localized
totals exceeding 3". While the global GFS and ECMWF are less
pronounced with their QPF swaths the GEM regional and UKMET are
more in line with the high res guidance. The AIFS and AIGFS also
depict a corridor of enhanced QPF that generally matches the Slight
risk placement. Beneath the closed low over KY and TN, convection
may be less organized, but slow moving. Given PWs near 2" and the
possibility of saturated soils from day 1 rainfall, a flash flood
risk should continue. Across the central and eastern Carolinas PWs
over 2" combined with low level southerly moisture transport and
backdoor frontal convergence should create an environment for high
rainfall rate driven flash flood potential.

Surrounding the Slight risk, a broad Marginal encompasses eastern
NM, TX and much of the Southeast. A southward advancing cold front,
the aforementioned mid level shortwave/low, and upper jet support
will provide the necessary synoptic forcing for scattered
convection. PWs over 2" and CAPE of 2000-3000 J/kg where daytime
heating is maximized, will support heavy rainfall rates. Some
mesoscale uncertainty exists with the track and strength of the
shortwave and frontal positions. An embedded Slight risk or two
may be needed on future updates as confidence increases. Increasing
low level westerly flow along the central Gulf Coast provides a
signature for backbuilding and training, but model divergence on
the exact axis remains. Given the higher regional FFG, did not
want to go with an overly large Slight risk at this time.

...Southwest...
Monsoonal moisture and instability will expand northwestward on
Sunday, necessitating a broader Marginal risk across AZ. While an
embedded Slight risk may eventually be needed, lingering questions
regarding storm coverage and organization keep the risk at
Marginal for now. Current indications suggest that while robust
convection will initiate over the terrain, it will propagate
westward quickly, potentially limiting the threat to isolate
instances of flash flooding.

Chenard

Day 3
Valid 12Z Mon Jul 13 2026 - 12Z Tue Jul 14 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE CENTRAL GULF COAST...

2000Z Update: Very few (subtle) changes made to the previous Day 3
ERO. See discussion below for more on the meteorological
reasoning, which per the latest (12Z) guidance/model trends, has
not changed much.

Hurley

...Central Gulf Coast to the Southeast...
The inherited Slight risk across portions of the central Gulf Coast
has been maintained and expanded both westward into southeast TX
and eastward into the FL Panhandle. A favorable synoptic and
mesoscale setup for training and backbuilding is forecast to align
with coastal areas. Enhanced west to northwesterly low level flow
south of the persistent shortwave/low over the TN/GA vicinity will
converge with southwesterly inflow off the Gulf. This configuration
is conducive for upwind propagation and some training convection.
While some uncertainty remains regarding how far inland the heavier
totals will reach, the moist airmass characterized by PWs around
2.25" will support heavy rainfall rates.

Further west, increasing low level southerly moisture transport
out of the western Gulf will push up the Rio Grande Valley and into
central TX, potentially resulting in convective clusters Monday
night. Future shifts may need to expand the Slight risk even
further into TX depending on how this threat evolves.

A broad Marginal risk remains in place from TN into the Southeast
and southern Mid-Atlantic, Similar to day 2, a lingering
shortwave/low will continue to interact with a backdoor frontal
zone. Model divergence exists regarding the exact positioning of
these features and the available instability footprint by this
time. Given this, and the fact that model QPF signals are a bit
more muted compared to Sunday, we will maintain the Marginal
risk...although an embedded Slight risk upgrade may still
eventually be needed as the mesoscale details clarify.

...Southwest...
A Marginal risk is maintained from southern NM into AZ, southeast
CA and southern NV. Deep monsoonal moisture will continue to push
northwestward with isolated to scattered convection expected TO
result in at least a localized flash food threat.

Chenard

Day 4 and Day 5

Valid 12Z Tue Jul 14 2026 - 12Z Thu Jul 16 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ALONG PARTS OF THE
CENTRAL GULF COAST ON MONDAY...

2030Z Update...

Daytime guidance did not indicate any need for significant changes,
therefore the update reflects only minor adjustments.

Pereira

Previous Discussion...
...Southeast U.S. into Texas...

Lingering effects from elevated moisture and slowly decaying
quasi-stationary front across the Southeast U.S. will lead to one
last period of elevated convective enhancements from east TX
through the southern half of the Southeastern CONUS. PWAT anomalies
will remain generally seasonal to perhaps upwards of +1 standard
deviations over the region, enough of a threat for heavy rain
prospects in a environment that favors relatively slower cell
motions. Considering the fact some of the Southeast will have
received a formidable amount of rainfall leading into the D4, some
localized flash flood concerns will linger for at least one more
day before finally waning into the D5 where the risk over the
Southeast is void and we settle into a more benign pattern overall.

Further west into the western half of TX, the same story cannot be
said as the pattern will begin shaping up into a much more
favorable flash flood environment thanks to a shift in the mid and
upper level pattern west of the Mississippi. Dominant ridging over
the top into the northern tier of the CONUS will give way to
a broad inverted trough axis migrating westward into the Southern
Plains as we move into the middle of next week leading to weakening
flow aloft and a myriad of smaller mid-level perturbations rotating
under the dominant cyclonic flow. Lowering heights and regional
forcing align to foster a more suitable convective environment
across the western half of TX with an emphasis currently on
west and southwest TX as noted via the multi-model consensus in
both the deterministic and ensemble outputs. Some of the guidance
is incredibly aggressive in their presentations with several inches
of rain in both the D4 and D5 time frames with a general maxima
located over the Lower Trans Pecos over into the neighboring
Edwards Plateau where the pattern would allow for greater low-level
convergence and prospects for organized convective clusters to
sneak out of Mexico (Mexican State of Coahuila). Considering a
solid agreement within the model suite this evening, felt confident
enough to introduce a SLGT risk across southwest TX over into the
Edwards Plateau and portions of the central RGV. This is certainly
an area to monitor closely as significant rainfall potential is
plausible in the current synoptic evolution being depicted.

...Southwest U.S...

The Southwestern U.S. will lie within the western flank of the
broad ridge pattern over the Central and Eastern U.S which will
provide a dominant southerly flow over the region allowing for
continued moisture advection and enhanced surface troughing over AZ
up through the Great Basin. This pattern is a continuation of the
Monsoonal presence out west with a potential for increasing flash
flood prospects as multi-day impacts could spur targeted
opportunities for repetition of areas getting hit by convection in
consecutive periods. This setup remains very stable in terms of the
broad synoptic pattern in place over the western CONUS, however we
will see a persistent moisture plume advect more formidable deep
layer moisture poleward as we move into early-mid next week leading
to PWAT anomalies pushing the 90-99th percentile according to the
NAEFS and 00z ECENS outputs. The strongest anomalies will lie
within the Great Basin up into the Northern Rockies on D4 with some modification by D5, but still very much entrenched within the upper
bounds of the anomalies, especially over the Northern Rockies and
Interior Northwest. Increased upper troughing migrating from the
west will slide under the ridge across the Northern CONUS leading
to an enhancement for convective potential over a broader scope by
D5 with widespread thunderstorm prospects aligned from the Canadian
border in MT down through the Inter-Mountain West into the
Southwestern deserts. This setup can lead to sneaky significant
rainfall prospects for those in the interior with a more typical
Monsoonal presentation in the convective coverage.

Given the above variables, the MRGL was expanded north and
northwest for D4 into the Great Basin with another MRGL risk added
across the Northern Rockies in the western half of MT and northern
ID. D5 is a broad MRGL risk for much of the Southwest and interior
west, including areas that were omitted from the previous period(s)
MRGL risks. There is potential for targeted SLGT risks to be issued
in future updates as we move closer to the event, so please check
back over the next several days as the pattern becomes much more
active and favorable for flash flood prospects.

Kleebauer

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!9W_aGLl-uBwbowpGccYu1Zn9uWfH9v07yrurhoGoGhywCu10EZwLBE6zKDpR2iHjIEdb6Kul36txw54s1sYPX7IEnsU$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!9W_aGLl-uBwbowpGccYu1Zn9uWfH9v07yrurhoGoGhywCu10EZwLBE6zKDpR2iHjIEdb6Kul36txw54s1sYPg6mnteE$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!9W_aGLl-uBwbowpGccYu1Zn9uWfH9v07yrurhoGoGhywCu10EZwLBE6zKDpR2iHjIEdb6Kul36txw54s1sYPH7MhhFM$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Jul 16 08:24:12 2026

FOUS30 KWBC 160823
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
423 AM EDT Thu Jul 16 2026

Day 1
Valid 12Z Thu Jul 16 2026 - 12Z Fri Jul 17 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE EDWARDS PLATEAU, CENTRAL RIO GRANDE VALLEY, AND HILL
COUNTRY. A MODERATE RISK IS ALSO IN PLACE OVER PORTIONS OF SOUTHERN
ARIZONA...

...Texas...

The persistent convective pattern centered near the Edwards Plateau
and southern Hill Country is expected to enter its final high-
impact phase this period. The high-end Moderate Risk has been
maintained over south-central Texas, centering on a corridor from
Val Verde and Crockett counties eastward into the southern Hill
Country. Extremely compromised soil conditions from multi-day
rainfall and very low flash flood guidance mean any additional
precipitation will exacerbate ongoing flooding. Convection that has
developed early this morning will likely linger past daybreak
around a slow-moving MCV, followed by another anticipated round of
locally heavy nocturnal storms late Thursday night into early
Friday morning. Both the HREF and REFS show robust probabilities
for additional rainfall totals exceeding 3 inches, with localized
narrow bands potentially reaching over 5 inches.

Farther north, the Slight Risk was extended into portions of
Northwest Texas. This expansion is supported by deep moisture
pooling along a low-to-mid level boundary, combined with shortwave
energy lifting northward out of the main system, which will fuel
scattered, high-rate convective cores capable of localized runoff
concerns.

...Southwest into the Great Basin...

No significant changes were made to the risk areas out West for
this update. A prime monsoonal setup remains in place for southern
Arizona, where a Moderate Risk remains in place. PWs are expected
to climb above 2 inches, or exceeding 2 std dev normal, across
portions of southern Arizona. This moisture along with sufficient
instability and upper level support, will likely support terrain-
initiated thunderstorms. Subsequent rain-cooled outflows will drive
additional intense cells into the evening hours, pushing rainfall
rates up 2 inches/hr in some locations. A broader Slight Risk
encompasses much of Arizona, extending north into the slot canyons
of southern Utah and eastward into far western New Mexico.

...Mid Mississippi Valley into the Lower Ohio/Tennessee Valleys
and Southern Appalachians...

The Marginal Risk has been adjusted and expanded father east,
stretching from the Mid Mississippi Valley into portions of the
lower Ohio and Tennessee valleys, as well as the southern
Appalachians. A remnant mid-level shortwave moving into the region
will provide weak ascent. Southwesterly inflow into a downstream
boundary will support deepening moisture (PWs increasing to 1.75-2
inches). Both the HREF and REFS guidance are showing notable
probabilities for localized rainfall totals exceeding 2 inches.
Hourly rainfall rates along the boundary may support isolated flash
flood occurrences, particularly in complex terrain and urban
areas.

Pereira

Day 2
Valid 12Z Fri Jul 17 2026 - 12Z Sat Jul 18 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS MUCH OF WEST
TEXAS, SOUTHERN NEW MEXICO, ARIZONA, AND THE SOUTHERN GREAT
BASIN...

...West Texas into Southern New Mexico...

A transition and decay in the high-impact heavy rain setup across
the Edwards Plateau and southern Hill Country is expected as the
mid-level trough over West Texas weakens and begins to dissolve.
However, despite the trend, lingering elevated moisture beneath the
lower height field will allow for scattered activity, mostly
northwest of the areas most severely impacted earlier in the week.

While the general forecast totals are lower than previous days,
localized heavy rates may result in additional concerns, especially
in areas left vulnerable by prior rounds of heavy rainfall.

In southern New Mexico, storms are expected to develop along and
near the Sacramento Mountains by the afternoon and continue into
the evening before diminishing with the loss of diurnal heating.
Active wildfire burn scars in this region make it particularly
susceptible to rapid runoffs, supporting the continuation of the
Slight Risk.

...Western U.S./Great Basin...

Overall, only minor changes were made to the risk areas in the
West, as a persistent monsoonal pattern remains locked in place.
A robust moisture profile will sustain widespread convective
coverage from southern Arizona north-northeastward into the Great
Basin. Moisture anomalies will remain high, with standardized
anomalies of 2-3 extending all the way from the Southwest to the
northern Rockies.

This moisture, along with with sufficient instability will support
highly efficient rainfall rates. A broad Slight Risk was maintained
from southern Arizona to southern Utah, with complex terrain,
urbanized areas, and other vulnerable areas likely to a be a focus
for the greater runoff concerns across the region.

...Ohio/Tennessee Valleys into the Central and Southern
Appalachians....

A Marginal Risk covering much of the Ohio and Tennessee Valleys
into the central and southern Appalachians was maintained. Storms
developing across this region will be fueled by the same high-PW
airmass noted in the Day 1 period as it spread farther north and
east. These diurnally-driven storms are once again expected to
raise isolated runoff concerns.

...Northern Great Lakes...

A progressive upper trough digging southeast across central Canada,
will shift a notable jet max south into northern Minnesota. Strong
low level convergence along with favorable upper jet forcing will
support nocturnal storms from the Minnesota Arrowhead eastward into
Upper Michigan. Although fast storm motions will the heavy
accumulation and flash flooding threat, anomalous moisture
supporting heavy rates, along with some potential for brief
training, may raise isolated concerns.

Pereira

Day 3
Valid 12Z Sat Jul 18 2026 - 12Z Sun Jul 19 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM WEST TEXAS AND
SOUTHERN NEW MEXICO TO SOUTHERN UTAH...

...Western U.S....

An expansive monsoonal convective pattern will continue, prompting
the inclusion of a Slight Risk stretching from West Texas and
southern New Mexico northwestward across Arizona and into southern
Utah. Overnight guidance indicated a notable uptick in low level
moisture transport into these region on Saturday. This surge will
act to revitalize the potential for additional rounds of high
rainfall rate convective cores capable of producing flash flooding.

Once again, the combination of anomalous moisture and instability
will support highly efficient rainfall rates within the stronger
storms. The threat of rapid runoff and flash flooding will be
elevated across the complex terrain, normally dry washes, and slot
canyons, as well as over highly sensitive soils and wildfire burn
scars.

...Ohio Valley/Central and Southern Appalachians to the Mid
Atlantic and Northeast...

The core of the high-PW airmass will continue to shift east, with
moisture pooling ahead of a strong cold front dropping south
across the Northeast. Strong synoptic forcing, driven by an
amplifying trough over the Northeast and favorable upper jet
dynamics, will support an axis of organized storms from the upper
Ohio Valley into the Northeast. Given the high PWs and strong
forcing, heavy rainfall rates producing at least localized runoff
concerns are expected. Given the uncertainty regarding where the
axis of heaviest rains will occur, maintained a Marginal Risk for
now. However, a targeted Slight Risk may be introduced in future
updates if confidence increases.

Pereira

Day 4 and Day 5

Valid 12Z Sun Jul 19 2026 - 12Z Tue Jul 21 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE WEST ON DAYS 4 AND 5, THE VIRGINIA TIDEWATER ON DAY 4, AND
PORTIONS OF FLORIDA ON DAYS 4 AND 5...

...Western U.S...

A traditional Monsoonal pattern will continue across the Western
CONUS with scattered to widespread bouts of heavy rainfall across
much of the Desert Southwest up through the Great Basin with an
northern inflection into portions of the Rockies. Ridging will
prevail across the west as we move through the weekend into early
next week with a solidified Monsoonal trough positioned over AZ
down through Mexico. Even at leads, there's a well- defined axis
of elevated instability coupling with PWAT anomalies between +2 and
+3 standard deviations positioned from the Great Basin to points
south with the strongest anomalies situated over NV and UT was
assessing both the ECENS and NAEFS anomaly forecast. QPF maxima
are currently situated within the Mogollon Rim and portions of
southern UT, both of which are the more susceptible areas given the
persistence of heavy rainfall leading in, plus the complex
topography and slot canyon allotment. This is really a seasonal
setup which could likely spur short term upgrades in spots as we
move closer to both the D4 and D5 time frame. Broad MRGL risks
exist for both days in similar locations outlining much of the
aforementioned area(s) above.

...Florida...

Models continue to depict heavy rainfall across the western coast
of FL on D4 (Sunday), spreading further east towards the northern
half of the state on D5 (Monday) thanks to developing mid-level
disturbance over the eastern Gulf. General model consensus is for a
development of heavier rains across the western FL coast with a
northern inflection into the Florida Big Bend thanks to increasing
low-level convergence on the eastern flank of a weak low center
progged off the coast. Ensemble QPF for both periods indicate
multiple inches of rain possible which could enhance further if
there is a greater likelihood of tropical cyclogenesis as noted via
the latest National Hurricane Center T.W.O for a disturbance of
interest (Disturbance 2) at 20% chance for development the next
7-days. This is a period to monitor for the prospects of this being
something more organized which models might not have a great grasp
of yet considering the lead time, and the slow maturation of any
organized low the next 5-7 days. For now, MRGL risks exist on both
D4 and D5 for the threat of heavy rainfall.

...Virginia Tidewater into Northeast North Carolina...

Slow-moving front will make headway through southeastern VA and
northeastern NC by Sunday with a deep moisture pooling anticipated
along and ahead of the front which will likely lead to areas of
heavy thunderstorms prior to fropa. Ensemble consensus lends
credence to a localized QPF maxima positioned somewhere around the
VA Tidewater through the northeastern corner of NC, coincident
with the progged frontal positioning around the time of Sunday
afternoon. PQPF for >1" is between 20-40% across the region which
at D4 is formidable enough to monitor closely. Considering some of
the more appreciable outputs via the global deterministic and bias
corrected ensemble, and in coordination with the local Wakefield,
VA WFO, opted to add a D4 MRGL risk for the threat, highlighting
that Tidewater area down into northeastern NC.

Kleebauer

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!-kPHlNyfS_sniVf3p26vYrQIJoOlUtsyAVp-0V8KqcsWlmNthk-tV14O3TZCmKxvMpgnFjucF5xguZ0tHxsWN8T3nCg$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!-kPHlNyfS_sniVf3p26vYrQIJoOlUtsyAVp-0V8KqcsWlmNthk-tV14O3TZCmKxvMpgnFjucF5xguZ0tHxsWp0ietb0$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!-kPHlNyfS_sniVf3p26vYrQIJoOlUtsyAVp-0V8KqcsWlmNthk-tV14O3TZCmKxvMpgnFjucF5xguZ0tHxsW3-0mG7U$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Jul 16 09:51:14 2026

FOUS30 KWBC 160950
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
550 AM EDT Thu Jul 16 2026

Day 1
Valid 12Z Thu Jul 16 2026 - 12Z Fri Jul 17 2026

...THERE IS A HIGH RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
SOUTH-CENTRAL TEXAS...

...Texas...

0930Z Update...
A High Risk was introduced at 0930Z across portions
of south-central Texas. This includes areas where heavy rainfall
continues to fall and drift slowly to the north. Areas of slow-
moving, heavy rainfall are expected to continue beyond 12Z,
exacerbating the catastrophic impacts that unfolded across
portions of the region overnight. The Moderate Risk was also
expanded a little farther to the north to account for the current
trends.

Previous discussion...
The persistent convective pattern centered near the Edwards Plateau
and southern Hill Country is expected to enter its final high-
impact phase this period. The high-end Moderate Risk has been
maintained over south-central Texas, centering on a corridor from
Val Verde and Crockett counties eastward into the southern Hill
Country. Extremely compromised soil conditions from multi-day
rainfall and very low flash flood guidance mean any additional
precipitation will exacerbate ongoing flooding. Convection that has
developed early this morning will likely linger past daybreak
around a slow-moving MCV, followed by another anticipated round of
locally heavy nocturnal storms late Thursday night into early
Friday morning. Both the HREF and REFS show robust probabilities
for additional rainfall totals exceeding 3 inches, with localized
narrow bands potentially reaching over 5 inches.

Farther north, the Slight Risk was extended into portions of
Northwest Texas. This expansion is supported by deep moisture
pooling along a low-to-mid level boundary, combined with shortwave
energy lifting northward out of the main system, which will fuel
scattered, high-rate convective cores capable of localized runoff
concerns.

...Southwest into the Great Basin...

No significant changes were made to the risk areas out West for
this update. A prime monsoonal setup remains in place for southern
Arizona, where a Moderate Risk remains in place. PWs are expected
to climb above 2 inches, or exceeding 2 std dev normal, across
portions of southern Arizona. This moisture along with sufficient
instability and upper level support, will likely support terrain-
initiated thunderstorms. Subsequent rain-cooled outflows will drive
additional intense cells into the evening hours, pushing rainfall
rates up 2 inches/hr in some locations. A broader Slight Risk
encompasses much of Arizona, extending north into the slot canyons
of southern Utah and eastward into far western New Mexico.

...Mid Mississippi Valley into the Lower Ohio/Tennessee Valleys
and Southern Appalachians...

The Marginal Risk has been adjusted and expanded father east,
stretching from the Mid Mississippi Valley into portions of the
lower Ohio and Tennessee valleys, as well as the southern
Appalachians. A remnant mid-level shortwave moving into the region
will provide weak ascent. Southwesterly inflow into a downstream
boundary will support deepening moisture (PWs increasing to 1.75-2
inches). Both the HREF and REFS guidance are showing notable
probabilities for localized rainfall totals exceeding 2 inches.
Hourly rainfall rates along the boundary may support isolated flash
flood occurrences, particularly in complex terrain and urban
areas.

Pereira

Day 2
Valid 12Z Fri Jul 17 2026 - 12Z Sat Jul 18 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS MUCH OF WEST
TEXAS, SOUTHERN NEW MEXICO, ARIZONA, AND THE SOUTHERN GREAT
BASIN...

...West Texas into Southern New Mexico...

A transition and decay in the high-impact heavy rain setup across
the Edwards Plateau and southern Hill Country is expected as the
mid-level trough over West Texas weakens and begins to dissolve.
However, despite the trend, lingering elevated moisture beneath the
lower height field will allow for scattered activity, mostly
northwest of the areas most severely impacted earlier in the week.

While the general forecast totals are lower than previous days,
localized heavy rates may result in additional concerns, especially
in areas left vulnerable by prior rounds of heavy rainfall.

In southern New Mexico, storms are expected to develop along and
near the Sacramento Mountains by the afternoon and continue into
the evening before diminishing with the loss of diurnal heating.
Active wildfire burn scars in this region make it particularly
susceptible to rapid runoffs, supporting the continuation of the
Slight Risk.

...Western U.S./Great Basin...

Overall, only minor changes were made to the risk areas in the
West, as a persistent monsoonal pattern remains locked in place.
A robust moisture profile will sustain widespread convective
coverage from southern Arizona north-northeastward into the Great
Basin. Moisture anomalies will remain high, with standardized
anomalies of 2-3 extending all the way from the Southwest to the
northern Rockies.

This moisture, along with with sufficient instability will support
highly efficient rainfall rates. A broad Slight Risk was maintained
from southern Arizona to southern Utah, with complex terrain,
urbanized areas, and other vulnerable areas likely to a be a focus
for the greater runoff concerns across the region.

...Ohio/Tennessee Valleys into the Central and Southern
Appalachians....

A Marginal Risk covering much of the Ohio and Tennessee Valleys
into the central and southern Appalachians was maintained. Storms
developing across this region will be fueled by the same high-PW
airmass noted in the Day 1 period as it spread farther north and
east. These diurnally-driven storms are once again expected to
raise isolated runoff concerns.

...Northern Great Lakes...

A progressive upper trough digging southeast across central Canada,
will shift a notable jet max south into northern Minnesota. Strong
low level convergence along with favorable upper jet forcing will
support nocturnal storms from the Minnesota Arrowhead eastward into
Upper Michigan. Although fast storm motions will the heavy
accumulation and flash flooding threat, anomalous moisture
supporting heavy rates, along with some potential for brief
training, may raise isolated concerns.

Pereira

Day 3
Valid 12Z Sat Jul 18 2026 - 12Z Sun Jul 19 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM WEST TEXAS AND
SOUTHERN NEW MEXICO TO SOUTHERN UTAH...

...Western U.S....

An expansive monsoonal convective pattern will continue, prompting
the inclusion of a Slight Risk stretching from West Texas and
southern New Mexico northwestward across Arizona and into southern
Utah. Overnight guidance indicated a notable uptick in low level
moisture transport into these region on Saturday. This surge will
act to revitalize the potential for additional rounds of high
rainfall rate convective cores capable of producing flash flooding.

Once again, the combination of anomalous moisture and instability
will support highly efficient rainfall rates within the stronger
storms. The threat of rapid runoff and flash flooding will be
elevated across the complex terrain, normally dry washes, and slot
canyons, as well as over highly sensitive soils and wildfire burn
scars.

...Ohio Valley/Central and Southern Appalachians to the Mid
Atlantic and Northeast...

The core of the high-PW airmass will continue to shift east, with
moisture pooling ahead of a strong cold front dropping south
across the Northeast. Strong synoptic forcing, driven by an
amplifying trough over the Northeast and favorable upper jet
dynamics, will support an axis of organized storms from the upper
Ohio Valley into the Northeast. Given the high PWs and strong
forcing, heavy rainfall rates producing at least localized runoff
concerns are expected. Given the uncertainty regarding where the
axis of heaviest rains will occur, maintained a Marginal Risk for
now. However, a targeted Slight Risk may be introduced in future
updates if confidence increases.

Pereira

Day 4 and Day 5

Valid 12Z Sun Jul 19 2026 - 12Z Tue Jul 21 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE WEST ON DAYS 4 AND 5, THE VIRGINIA TIDEWATER ON DAY 4, AND
PORTIONS OF FLORIDA ON DAYS 4 AND 5...

...Western U.S...

A traditional Monsoonal pattern will continue across the Western
CONUS with scattered to widespread bouts of heavy rainfall across
much of the Desert Southwest up through the Great Basin with an
northern inflection into portions of the Rockies. Ridging will
prevail across the west as we move through the weekend into early
next week with a solidified Monsoonal trough positioned over AZ
down through Mexico. Even at leads, there's a well- defined axis
of elevated instability coupling with PWAT anomalies between +2 and
+3 standard deviations positioned from the Great Basin to points
south with the strongest anomalies situated over NV and UT was
assessing both the ECENS and NAEFS anomaly forecast. QPF maxima
are currently situated within the Mogollon Rim and portions of
southern UT, both of which are the more susceptible areas given the
persistence of heavy rainfall leading in, plus the complex
topography and slot canyon allotment. This is really a seasonal
setup which could likely spur short term upgrades in spots as we
move closer to both the D4 and D5 time frame. Broad MRGL risks
exist for both days in similar locations outlining much of the
aforementioned area(s) above.

...Florida...

Models continue to depict heavy rainfall across the western coast
of FL on D4 (Sunday), spreading further east towards the northern
half of the state on D5 (Monday) thanks to developing mid-level
disturbance over the eastern Gulf. General model consensus is for a
development of heavier rains across the western FL coast with a
northern inflection into the Florida Big Bend thanks to increasing
low-level convergence on the eastern flank of a weak low center
progged off the coast. Ensemble QPF for both periods indicate
multiple inches of rain possible which could enhance further if
there is a greater likelihood of tropical cyclogenesis as noted via
the latest National Hurricane Center T.W.O for a disturbance of
interest (Disturbance 2) at 20% chance for development the next
7-days. This is a period to monitor for the prospects of this being
something more organized which models might not have a great grasp
of yet considering the lead time, and the slow maturation of any
organized low the next 5-7 days. For now, MRGL risks exist on both
D4 and D5 for the threat of heavy rainfall.

...Virginia Tidewater into Northeast North Carolina...

Slow-moving front will make headway through southeastern VA and
northeastern NC by Sunday with a deep moisture pooling anticipated
along and ahead of the front which will likely lead to areas of
heavy thunderstorms prior to fropa. Ensemble consensus lends
credence to a localized QPF maxima positioned somewhere around the
VA Tidewater through the northeastern corner of NC, coincident
with the progged frontal positioning around the time of Sunday
afternoon. PQPF for >1" is between 20-40% across the region which
at D4 is formidable enough to monitor closely. Considering some of
the more appreciable outputs via the global deterministic and bias
corrected ensemble, and in coordination with the local Wakefield,
VA WFO, opted to add a D4 MRGL risk for the threat, highlighting
that Tidewater area down into northeastern NC.

Kleebauer

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!8WyPRQXtNdL7B0Ftgqd1GZOzO1FUKNn8ElKlsfQFrlIknS_b3c_-vcCjoCosXW7BgcfkvZxiZ1on7x06CE3Xg-PRFvI$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!8WyPRQXtNdL7B0Ftgqd1GZOzO1FUKNn8ElKlsfQFrlIknS_b3c_-vcCjoCosXW7BgcfkvZxiZ1on7x06CE3XJqtYDZA$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!8WyPRQXtNdL7B0Ftgqd1GZOzO1FUKNn8ElKlsfQFrlIknS_b3c_-vcCjoCosXW7BgcfkvZxiZ1on7x06CE3XElgzn54$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Fri Jul 17 00:51:50 2026

FOUS30 KWBC 170051
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
851 PM EDT Thu Jul 16 2026

Day 1
Valid 01Z Fri Jul 17 2026 - 12Z Fri Jul 17 2026

...THERE IS A HIGH RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
SOUTH-CENTRAL TEXAS...

01Z Update...
Previous update captured the evolution of convection well so only
some minor nudging of the risk area boundaries were needed. Texas
remained the prime candidate for catastrophic and life-threatening
flash flooding in the overnight hours given additional rainfall
on top of what has already overwhelmed some places. The channel of moisture/instability fueling convection from Arizona/southwestern
New Mexico northward into parts of Wyoming and Montanan pretty well established...changes were pretty small and largely made to fit
the latest radar trends.

Bann

16Z Update...

...Texas...

Catastrophic and life-threatening flash flooding continues in
the Texas Hill Country as the pain-stakingly slow MCV responsible
for the copious amounts of rainfall in recent days continues to
cause widespread excessive rainfall rates. Through the early
afternoon, the low-level jet will continue to supply low-level
moisture and shear into the Hill Country, helping to sustain the
current thunderstorm activity and their prolific rainfall rates
between 2-4"/hr in many cases. Meanwhile, 700mb flow is convergent
west of the Rio Grande and is aiding in providing some mid-level
ascent on the southern and eastern flanks of the MCV. WPC's
Metwatch issued an MPD (#740) that goes into more detail on the
evolving setup through early afternoon.

CAMs generally show the same pattern as recent days with thunderstorms decreasing in areal coverage later this afternoon, only to re-
develop overnight as the low-level jet strengthens and diffluent
500-700mb flow supports upscale ascent. PWs tonight will continue
to be highly anomalous (>2.0") over the Hill Country on north and
west through north-central TX and the Edwards Plateau. The ongoing
stream of Gulf moisture will also accompany additional instability
as well, priming the atmosphere for another round of widespread
storms in areas hit this morning and even a little farther north
and west that include areas north and east of Del Rio towards the
Concho Valley. CAMs continue to disagree on exact placement, but
recent days of thunderstorm activity would suggest the more
southern and eastern envelope of solutions should be favored. New
12Z HREF and REFS shows moderate-to-high chances (50-70%) for >5"
of rainfall north and east of Del Rio, TX with a highly concerning
30-50% area for >8" through 12Z Friday when utilizing both ensemble
suites.

The High Risk was expanded a little farther N&W into areas north
and east of Del Rio where the remnant MCV will be tracking across
tonight, and the Moderate Risk encompasses more of the Concho
Valley. The region is facing tremendous ongoing impacts from
urban, stream, and river flooding and any additional rainfall is
going to exacerbate this ongoing catastrophic event. TX Hill
Country residents should continue to follow guidance from local
officials and maintain multiple ways to receive weather alerts
during this ongoing flood disaster.

...Elsewhere...

The Slight Risk in Arizona and southern Utah remains in good shape,
although there are locally some moderate chance probabilities
(40-60%) between the 12Z HREF and REFS for >3" of rainfall along
the southern periphery of the Mogollon Rim. The setup has more of a
look of a high-end Slight here, as areal extent of flash flooding
may not be high enough to warrant a Moderate Risk, but locally
significant flash flooding cannot be ruled out given the
sensitivities of the region and the potential 2"/hr rainfall rates.
The Marginal Risk was maintained from the Middle MS Valley on east
to the TN Valley. Signals in probabilistic guidance are not in
great agreement on exactly where to favor a Slight Risk at the
moment. That said, the Lower OH Valley and TN Valleys have 1-hr
FFGs that are <2" today and could be more favored for areas of localized
flash flooding this afternoon.

Mullinax

---Previous Discussion---

...Southwest into the Great Basin...

No significant changes were made to the risk areas out West for
this update. A prime monsoonal setup remains in place for southern
Arizona, where a Moderate Risk remains in place. PWs are expected
to climb above 2 inches, or exceeding 2 std dev normal, across
portions of southern Arizona. This moisture along with sufficient
instability and upper level support, will likely support terrain-
initiated thunderstorms. Subsequent rain-cooled outflows will drive
additional intense cells into the evening hours, pushing rainfall
rates up 2 inches/hr in some locations. A broader Slight Risk
encompasses much of Arizona, extending north into the slot canyons
of southern Utah and eastward into far western New Mexico.

...Mid Mississippi Valley into the Lower Ohio/Tennessee Valleys
and Southern Appalachians...

The Marginal Risk has been adjusted and expanded father east,
stretching from the Mid Mississippi Valley into portions of the
lower Ohio and Tennessee valleys, as well as the southern
Appalachians. A remnant mid-level shortwave moving into the region
will provide weak ascent. Southwesterly inflow into a downstream
boundary will support deepening moisture (PWs increasing to 1.75-2
inches). Both the HREF and REFS guidance are showing notable
probabilities for localized rainfall totals exceeding 2 inches.
Hourly rainfall rates along the boundary may support isolated flash
flood occurrences, particularly in complex terrain and urban
areas.

Pereira

Day 2
Valid 12Z Fri Jul 17 2026 - 12Z Sat Jul 18 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS MUCH OF WEST
TEXAS, SOUTHERN NEW MEXICO, ARIZONA, AND THE SOUTHERN GREAT
BASIN...

20Z Update...

...Texas...

The MCV responsible for the catastrophic flooding in the Hill
Country will finally begin to make its way N&W on Friday. There
remains concern that the eastern and southern flanks will be close
enough to affected areas of central TX to further exacerbate flash
flooding, as well as along streams, creeks, and rivers. Moisture
content will remain quite anomalous for the time of year (1.8-2.0",
above the 90th climatological percentile) for much of central TX. A
revitalized low-level jet will also play a prominent role in
supplying both low-level moisture/theta-e advection, additional
MUCAPE, and an increase in low-level shear, giving storms
additional longevity into the late morning hours. CAMs show less
areal coverage compared to recent days, but given the strength of
the low-level jet (surpassing 30 kts) it will provide sufficient
inflow and some upslope enhancement into western portions of the
Hill Country and the Edwards Plateau through midday. The gradual
westward shift will mean more scattered to widespread showers and
storms throughout West Texas, and hourly rainfall rates around
2"/hr are possible even towards the Davis Mountains.

Most probabilistic guidance is at least in better agreement on an
axis of thunderstorms from the Rio Grande on north through the
Edwards Plateau and the Conch Valley Friday morning. Rainfall rates
between 2-3"/hr with peak maximum approaching 4"/hr remain
possible. In total, another 2-6" of rainfall is possible late
tonight and through Friday morning within that band of thunderstorm
activity, with locally higher amounts possible within the Slight
Risk from Del Rio on north to the Concho Valley. Additional
flash flooding is expected with significant flooding possible.
Should any storms ensue over areas hit in recent days over the Hill
Country, it could rejuvenate areas with lingering flood waters and
may result in renewed areas of dangerous flooding.

...Western Florida...

A cut-off 500mb low just west of Tampa Bay will reside within an
area where PWs between 2.0-2.2", which is hovering around the 90th climatological percentile. MLCAPE over 1,000 J/kg and warm cloud
layers approaching 14,000' deep will provide developing
thunderstorms with a favorable environment to generate highly
efficient rainfall rates that could surpass 3"/hr in the most
intense cells. Given the greater Tampa/St. Petersburg area may also
have slightly more sensitive soils following today's storms, it is
possible localized flash flooding occurs within the more urbanized
areas of west-central FL. For these reasons, a Marginal Risk was
introduced this forecast update.

...Northern Arizona...

Newest 12Z HREF/12Z REFS guidance has shown an increased signal for

3" and locally >5" rainfall totals in portions of the Mogollon Rim

for Friday. On the heels of an active Thursday, it is possible the
atmosphere is more over-worked and struggle to produce the too
excessive of rates. On the flip side, soils will be more sensitive
to additional thunderstorms. The setup supports a more "high-end"
Slight in the Mogollon Rim, suggesting more scattered instances of
flash flooding with the potential for localized significant flash
flooding, particularly near burn scars and dry washes.

Mullinax

---Previous Discussion---

...Southern New Mexico...

In southern New Mexico, storms are expected to develop along and
near the Sacramento Mountains by the afternoon and continue into
the evening before diminishing with the loss of diurnal heating.
Active wildfire burn scars in this region make it particularly
susceptible to rapid runoffs, supporting the continuation of the
Slight Risk.

...Western U.S./Great Basin...

Overall, only minor changes were made to the risk areas in the
West, as a persistent monsoonal pattern remains locked in place.
A robust moisture profile will sustain widespread convective
coverage from southern Arizona north-northeastward into the Great
Basin. Moisture anomalies will remain high, with standardized
anomalies of 2-3 extending all the way from the Southwest to the
northern Rockies.

This moisture, along with with sufficient instability will support
highly efficient rainfall rates. A broad Slight Risk was maintained
from southern Arizona to southern Utah, with complex terrain,
urbanized areas, and other vulnerable areas likely to a be a focus
for the greater runoff concerns across the region.

...Ohio/Tennessee Valleys into the Central and Southern
Appalachians....

A Marginal Risk covering much of the Ohio and Tennessee Valleys
into the central and southern Appalachians was maintained. Storms
developing across this region will be fueled by the same high-PW
airmass noted in the Day 1 period as it spread farther north and
east. These diurnally-driven storms are once again expected to
raise isolated runoff concerns.

...Northern Great Lakes...

A progressive upper trough digging southeast across central Canada,
will shift a notable jet max south into northern Minnesota. Strong
low level convergence along with favorable upper jet forcing will
support nocturnal storms from the Minnesota Arrowhead eastward into
Upper Michigan. Although fast storm motions will the heavy
accumulation and flash flooding threat, anomalous moisture
supporting heavy rates, along with some potential for brief
training, may raise isolated concerns.

Pereira

Day 3
Valid 12Z Sat Jul 18 2026 - 12Z Sun Jul 19 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM WEST TEXAS AND
SOUTHERN NEW MEXICO TO SOUTHERN UTAH, AND OVER PORTIONS OF THE
NORTHERN MID-ATLANTIC...

20Z Update...

...Northern Mid-Atlantic...

A deepening area of low pressure in southern Ontario will work in
tandem with high pressure south of Bermuda to cause an acceleration
in southerly low-level winds over the Northern Mid-Atlantic
Saturday morning and into the afternoon hours. PWs will jump to
above 2.0" Saturday morning for areas such as northern MD,
southeast PA, all of NJ, and northward through NYC/Long Island and
along the southern New England coast. In the northern DelMarVa and
Delaware Valley, some guidance shows >2.2" PWs which tops the 97.5 climatological percentile. Strong low-level flow and rising dew
points will support pre-frontal thunderstorm activity Saturday
afternoon; some cases firing off the higher terrain to the west,
and in other cases through strong daytime heating and mid-70s dew
points simply breaking the capping inversion. Sufficient wind shear
will also be present to support potential mesocyclones, which
would further enhance excessive rainfall rates.

Surface winds out of the south to start the day would help direct
high theta-e air over the Chesapeake into these areas initially and
provide a more buoyant air-mass to support hourly rainfall rates
approaching 3"/hr. Additionally, various model guidance shows a
corridor of >2,000 J/kg MLCAPE moving from northeast MD into the
Delaware Valley Saturday afternoon. Given the region in the Slight
also sports a larger urbanized population, rainfall rates to this
caliber would be a recipe for flash flooding with such a high
concentration of hydrophobic surfaces. Parts of the Lehigh and
Susquehanna Valleys may be a little more resilient initially, but
additional thunderstorms look to come through Saturday evening as
the cold front approaches. In collaboration with PHI/CTP/LWX, a
Slight Risk was issued for portions of northeast MD, northern DE,
eastern PA, and much of NJ, while also including the greater
Philadelphia metro area. Should more guidance come into better
consensus on the positioning of heaviest rainfall over the I-95
corridor, the Slight Risk could see additional expansion in future
forecast cycles.

Mullinax

---Previous Discussion---

...Western U.S....

An expansive monsoonal convective pattern will continue, prompting
the inclusion of a Slight Risk stretching from West Texas and
southern New Mexico northwestward across Arizona and into southern
Utah. Overnight guidance indicated a notable uptick in low level
moisture transport into these region on Saturday. This surge will
act to revitalize the potential for additional rounds of high
rainfall rate convective cores capable of producing flash flooding.

Once again, the combination of anomalous moisture and instability
will support highly efficient rainfall rates within the stronger
storms. The threat of rapid runoff and flash flooding will be
elevated across the complex terrain, normally dry washes, and slot
canyons, as well as over highly sensitive soils and wildfire burn
scars.

...Ohio Valley/Central and Southern Appalachians to the Mid
Atlantic and Northeast...

The core of the high-PW airmass will continue to shift east, with
moisture pooling ahead of a strong cold front dropping south
across the Northeast. Strong synoptic forcing, driven by an
amplifying trough over the Northeast and favorable upper jet
dynamics, will support an axis of organized storms from the upper
Ohio Valley into the Northeast. Given the high PWs and strong
forcing, heavy rainfall rates producing at least localized runoff
concerns are expected. Given the uncertainty regarding where the
axis of heaviest rains will occur, maintained a Marginal Risk for
now. However, a targeted Slight Risk may be introduced in future
updates if confidence increases.

Pereira

Day 4 and Day 5

Valid 12Z Sun Jul 19 2026 - 12Z Tue Jul 21 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE WEST ON DAYS 4 AND 5, THE VIRGINIA TIDEWATER ON DAY 4, AND
PORTIONS OF FLORIDA ON DAYS 4 AND 5...

2030Z Update...
Models still depict an active pattern between a risk of excessive
rainfall to portions of the western United States and parts of the eastern/southeastern part of the country. Little run to run change
in the synoptic pattern meant little change in the QPF associated
with the monsoon in the western United States, Placement and timing
of QPF and any associated risk of excessive flooding in
Florida/adjacent part of the southeastern US states needed little
adjustment based on latest guidance.

Bann

Previous Discussion...

...Western U.S...

A traditional Monsoonal pattern will continue across the Western
CONUS with scattered to widespread bouts of heavy rainfall across
much of the Desert Southwest up through the Great Basin with an
northern inflection into portions of the Rockies. Ridging will
prevail across the west as we move through the weekend into early
next week with a solidified Monsoonal trough positioned over AZ
down through Mexico. Even at leads, there's a well- defined axis
of elevated instability coupling with PWAT anomalies between +2 and
+3 standard deviations positioned from the Great Basin to points
south with the strongest anomalies situated over NV and UT was
assessing both the ECENS and NAEFS anomaly forecast. QPF maxima
are currently situated within the Mogollon Rim and portions of
southern UT, both of which are the more susceptible areas given the
persistence of heavy rainfall leading in, plus the complex
topography and slot canyon allotment. This is really a seasonal
setup which could likely spur short term upgrades in spots as we
move closer to both the D4 and D5 time frame. Broad MRGL risks
exist for both days in similar locations outlining much of the
aforementioned area(s) above.

...Florida...

Models continue to depict heavy rainfall across the western coast
of FL on D4 (Sunday), spreading further east towards the northern
half of the state on D5 (Monday) thanks to developing mid-level
disturbance over the eastern Gulf. General model consensus is for a
development of heavier rains across the western FL coast with a
northern inflection into the Florida Big Bend thanks to increasing
low-level convergence on the eastern flank of a weak low center
progged off the coast. Ensemble QPF for both periods indicate
multiple inches of rain possible which could enhance further if
there is a greater likelihood of tropical cyclogenesis as noted via
the latest National Hurricane Center T.W.O for a disturbance of
interest (Disturbance 2) at 20% chance for development the next
7-days. This is a period to monitor for the prospects of this being
something more organized which models might not have a great grasp
of yet considering the lead time, and the slow maturation of any
organized low the next 5-7 days. For now, MRGL risks exist on both
D4 and D5 for the threat of heavy rainfall.

...Virginia Tidewater into Northeast North Carolina...

Slow-moving front will make headway through southeastern VA and
northeastern NC by Sunday with a deep moisture pooling anticipated
along and ahead of the front which will likely lead to areas of
heavy thunderstorms prior to fropa. Ensemble consensus lends
credence to a localized QPF maxima positioned somewhere around the
VA Tidewater through the northeastern corner of NC, coincident
with the progged frontal positioning around the time of Sunday
afternoon. PQPF for >1" is between 20-40% across the region which
at D4 is formidable enough to monitor closely. Considering some of
the more appreciable outputs via the global deterministic and bias
corrected ensemble, and in coordination with the local Wakefield,
VA WFO, opted to add a D4 MRGL risk for the threat, highlighting
that Tidewater area down into northeastern NC.

Kleebauer

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!5CJtK1OzhEq1I_djA0icpp4tF2-A5g1ejTQSHzPDhzwb_en-jNhGhUxjMRH6OL3n-RS1M-QR6rl7CqOpAYjWxFWNp5k$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!5CJtK1OzhEq1I_djA0icpp4tF2-A5g1ejTQSHzPDhzwb_en-jNhGhUxjMRH6OL3n-RS1M-QR6rl7CqOpAYjW4--XIIs$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!5CJtK1OzhEq1I_djA0icpp4tF2-A5g1ejTQSHzPDhzwb_en-jNhGhUxjMRH6OL3n-RS1M-QR6rl7CqOpAYjWxwmT0MA$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Fri Jul 17 08:25:02 2026

FOUS30 KWBC 170824
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
424 AM EDT Fri Jul 17 2026

Day 1
Valid 12Z Fri Jul 17 2026 - 12Z Sat Jul 18 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS MUCH OF WEST
TEXAS, SOUTHERN NEW MEXICO, ARIZONA, AND THE SOUTHERN GREAT
BASIN...

...Western U.S....
A persistent monsoonal pattern will remain in place across the
West, supporting widespread convective coverage. Standardized
moisture anomalies of 2-3+ std dev extend from Arizona and
southern California to the northern Rockies, sustaining a broadly
unstable environment conducive to highly efficient rainfall.

A "high-end" Slight Risk remains centered along northern Arizona's
Mogollon Rim. The HREF and REFS guidance have remained consistent
in signaling the potential for localized amounts of 3+ inches in
this area, raising the potential for scattered to localized
significant flash flooding, especially given the already moist soil
conditions. Additionally, the Slight has been expanded eastward to
encompass portions of northeastern Arizona and northwestern New
Mexico, where HREF and REFS are also indicating the threat for
localized heavy amounts (2-3 inches).

Farther south and east, storms are expected to develop along the
Sacramento Mountains of southern New Mexico, threatening active
wildfire burn scars susceptible to rapid runoff.

...Texas...
Lingering mid-level energy over south-central Texas will slowly
track north and west on Friday. The overnight hi-res models
continued to suggest significantly less coverage of heavy amounts
than in previous days. However, remaining deep moisture, along
with a revitalized 30+ kt low level jet, will maintain at least a
localized threat for additional heavy rains and therefore a Slight
Risk covering much of Southwest to South-Central Texas was
maintained. Fortunately, the general consensus of the HREF and REFS
indicates the greater threat for heavy amounts will center west of
the areas most severely impacted earlier this week and closer to
the Davis Mountains today. Farther north, moisture and energy
lifting out will carry some potential for localized heavy rain and
perhaps isolated flash flooding into parts of Northwest Texas,
where a broad Marginal Risk was maintained.

...Western Florida...
A cut-off 500mb low lingering over the eastern Gulf will reside in
a favorable environment for highly-efficient rainfall (PWs at or
above 2 inches, MLCAPE over 1,000 J/kg, and deep warm-cloud
depths). This will easily support rainfall rates exceeding 3 in/hr.
Therefore, a Marginal Risk was maintained along portions of
Florida's West Coast, highlighting the potential for isolated
runoff concerns, especially in urbanized areas.

...Ohio/Tennessee Valley to the Central/Southern Appalachians...
A Marginal Risk was maintained as a broad, high-PW airmass
continues to spread north and east, with the expectation that
diurnally-driven storms may produce isolated, short-duration
runoff concerns this afternoon and evening.

...Northern Great Lakes...
A progressive upper trough and associated jet max diving into
northern Minnesota will initiate nocturnal convection from northern
Minnesota into Upper Michigan. While rapid storm motions should
limit widespread heavy accumulations, anomalous moisture and
localized training profiles may produce isolated runoff concerns
within the area highlighted by the Marginal Risk.

Pereira

Day 2
Valid 12Z Sat Jul 18 2026 - 12Z Sun Jul 19 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM WEST TEXAS AND
SOUTHERN NEW MEXICO TO SOUTHERN UTAH, AND FROM THE NORTHERN MID-
ATLANTIC INTO SOUTHERN NEW YORK AND NEW ENGLAND...

...Western U.S.....
An expansive monsoonal convective pattern remains locked in place
across the Western CONUS, supporting the continuation of a broad
Slight Risk extending from West Texas and southern New Mexico
northwestward across central and northern Arizona into southern
Utah. An increase in low level moisture transport into the region,
coupled with the moisture already in place will support PW
anomalies 1.5-3 std dev above normal across much of this region.
This moisture will likely once again support widespread convective
development across the area. With ample daytime heating and
sufficient instability, these storms will be capable of producing
efficient rainfall rates. Given the history of recent
precipitation, soils have become increasingly sensitive across
portions of the region, elevating the potential for rapid runoff
and flash flooding concerns.

...Ohio Valley/Appalachians to the Mid Atlantic and Northeast...
A progressive cold front dropping southeastward will interact with
an anomalously moist airmass pooling ahead of it. Atmospheric
profiles will be highly favorable for efficient warm-rain
processes, featuring PWs over 2 inches and deep warm-cloud layers.
Where daytime heating and mid-70s dewpoints break capping
inversions, prefrontal convection will tap into greater instability
and raise rainfall rates.

This environment along with the concentration of urbanized areas
susceptible to fast runoff provided enough confidence to extend
the Slight Risk farther east from parts of eastern Pennsylvania and
northern New Jersey across southern New York and New England.
Limiting factors to highlighting a more widespread flash flooding
threat include fast storm moisture and lingering model discrepancy
regarding the exact placement of the heaviest precipitation axes.

Farther west through the central Appalachians into the Ohio Valley,
a broader Marginal Risk remains in place to cover what is
anticipated to be more isolated concerns.

Pereira

Day 3
Valid 12Z Sun Jul 19 2026 - 12Z Mon Jul 20 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
THE WESTERN U.S., FLORIDA GULF COAST, SOUTHEASTERN VIRGINIA AND
EASTERN NORTH CAROLINA...

...Western U.S....
The monsoon pattern will persist across the Western CONUS,
maintaining at least scattered convection from the West Texas, New
Mexico and Arizona into the Great Basin and Rockies. PW anomalies
of 2-3+ standard deviations will continue to center over portions
of the Great Basin. The higher areal average precipitation amounts
are expected to once again align along the Mogollon Rim into
southern Utah. Given the prior rainfall and moist soil conditions,
these areas will remain vulnerable to rapid runoff, with the
area's complex terrain and slot canyons raising localized concerns.
A broad Marginal Risk was maintained to highlight the daily
convective potential and runoff concerns.

...Florida Gulf Coast...
Deep tropical moisture and a slow-moving mid-to-upper level low
over the eastern Gulf will maintain a heavy rainfall threat.
Favorable low-level convergence along the eastern flank of the
system may produce heavy rainfall along Florida's West Coast. Some
models show the system lifting out to the north this period,
bringing the threat for heavy rain into the Big Bend region. A
Marginal Risk was maintained from the Tampa Bay area to the Big
Bend to highlight the potential for heavy rain along this area.

...Virginia Tidewater and Eastern North Carolina....
A cold front dropping out of the north is expected to slow across
this region, maintaining a deep moisture pool in advance. Pre-
frontal convergence and diurnal heating will likely produce pockets
of heavy, slow-moving thunderstorms prior to its passage. With
some differences in the details, model consensus continues to
indicate that 1-2 inch, with locally heavier amounts, are likely
within the Marginal Risk area, producing at least isolated concerns.
A targeted upgrade to a Slight may be required, especially if the
model consensus for heavy amounts begins to center across the more
vulnerable Tidewater region.

Pereira

Day 4 and Day 5

Valid 12Z Mon Jul 20 2026 - 12Z Wed Jul 22 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE NORTHEAST/MID ATLANTIC REGION...

...Western U.S...

A continuation of a traditional monsoonal pattern will continue
across the Western CONUS with scattered to widespread bouts of
locally heavy to excessive rainfall each day across much of the
Desert Southwest up through the Great Basin and into portions of
the Rockies. Deep moisture will be drawn northward around the
periphery of a building upper high extending from the Great Basin
to the Southern Plains. This sets up a well-defined axis of
elevated instability coupling with precipitable water anomalies
between +2 and +3 standard deviations above climatology for
July...with the strongest anomalies situated over Nevada and Utah.
QPF maxima are currently situated within the Mogollon Rim and
portions of southern Utah...both of which are the more susceptible
areas given the complex topography and slot canyons. Broad MRGL
risks exist for both days in similar locations outlining much of
the aforementioned area(s) above although short term upgrades in
spots are not our of the question.

...Florida...

Models continue to depict heavy rainfall across portions of the
northern Florida peninsula on Monday (Day 4) which spreads farther
northward in association with an area of low pressure. Ensemble
QPF for both periods indicate multiple inches of rain. This
continues to be a period to monitor for the prospects of this
being something becoming more organized than what the latest model
guidance indicates. For now, MRGL risks exist on both D4 and D5
for the threat of heavy rainfall.

Northeast US...

The deepening of a mid- and upper level trough by a digging upper
level jet will push a surface cold front into the Northeast US.
Deep moisture gets drawn northeastward ahead of the digging system
and should be in place as convection develops in vicinity of the
front. With such a moist environment and favorable low level
instability along with the upper support afforded by the
jet...downpours that lead to heavy or excessive rainfall amount are
possible.

Bann

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!7o2vHJ8Ig_QOA2FYGj8XtiZIjeFTC4FvysAYMuYRbyqkPv3oXiKyOHO63UeBvHhgvkmvxOhXWoQJablFa_Tj8qkW2tc$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!7o2vHJ8Ig_QOA2FYGj8XtiZIjeFTC4FvysAYMuYRbyqkPv3oXiKyOHO63UeBvHhgvkmvxOhXWoQJablFa_Tjz8ZiK0c$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!7o2vHJ8Ig_QOA2FYGj8XtiZIjeFTC4FvysAYMuYRbyqkPv3oXiKyOHO63UeBvHhgvkmvxOhXWoQJablFa_TjyPp7fb0$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Fri Jul 17 16:00:08 2026

FOUS30 KWBC 171559
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1159 AM EDT Fri Jul 17 2026

Day 1
Valid 16Z Fri Jul 17 2026 - 12Z Sat Jul 18 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS MUCH OF WEST
TEXAS, SOUTHERN NEW MEXICO, ARIZONA, AND THE SOUTHERN GREAT
BASIN...

1600Z Update: There were 2 notable adjustments made to the Day 1
ERO, both within Slight Risk areas. The Slight Risk in western AZ
and far southeast NV was expanded westward a bit to include the Las
Vegas metro region, while the Slight across parts of Central TX was
expanded northward to include Abilene and areas east of Midland.
Both of these adjustments were based on current observational
trends (especially with the meso-enhanced vort lobe in TX), along
with the 12Z HREF and REFS QPF exceedance probabilities.

Hurley

Previous discussion...

...Western U.S....
A persistent monsoonal pattern will remain in place across the
West, supporting widespread convective coverage. Standardized
moisture anomalies of 2-3+ std dev extend from Arizona and
southern California to the northern Rockies, sustaining a broadly
unstable environment conducive to highly efficient rainfall.

A "high-end" Slight Risk remains centered along northern Arizona's
Mogollon Rim. The HREF and REFS guidance have remained consistent
in signaling the potential for localized amounts of 3+ inches in
this area, raising the potential for scattered to localized
significant flash flooding, especially given the already moist soil
conditions. Additionally, the Slight has been expanded eastward to
encompass portions of northeastern Arizona and northwestern New
Mexico, where HREF and REFS are also indicating the threat for
localized heavy amounts (2-3 inches).

Farther south and east, storms are expected to develop along the
Sacramento Mountains of southern New Mexico, threatening active
wildfire burn scars susceptible to rapid runoff.

...Texas...
Lingering mid-level energy over south-central Texas will slowly
track north and west on Friday. The overnight hi-res models
continued to suggest significantly less coverage of heavy amounts
than in previous days. However, remaining deep moisture, along
with a revitalized 30+ kt low level jet, will maintain at least a
localized threat for additional heavy rains and therefore a Slight
Risk covering much of Southwest to South-Central Texas was
maintained. Fortunately, the general consensus of the HREF and REFS
indicates the greater threat for heavy amounts will center west of
the areas most severely impacted earlier this week and closer to
the Davis Mountains today. Farther north, moisture and energy
lifting out will carry some potential for localized heavy rain and
perhaps isolated flash flooding into parts of Northwest Texas,
where a broad Marginal Risk was maintained.

...Western Florida...
A cut-off 500mb low lingering over the eastern Gulf will reside in
a favorable environment for highly-efficient rainfall (PWs at or
above 2 inches, MLCAPE over 1,000 J/kg, and deep warm-cloud
depths). This will easily support rainfall rates exceeding 3 in/hr.
Therefore, a Marginal Risk was maintained along portions of
Florida's West Coast, highlighting the potential for isolated
runoff concerns, especially in urbanized areas.

...Ohio/Tennessee Valley to the Central/Southern Appalachians...
A Marginal Risk was maintained as a broad, high-PW airmass
continues to spread north and east, with the expectation that
diurnally-driven storms may produce isolated, short-duration
runoff concerns this afternoon and evening.

...Northern Great Lakes...
A progressive upper trough and associated jet max diving into
northern Minnesota will initiate nocturnal convection from northern
Minnesota into Upper Michigan. While rapid storm motions should
limit widespread heavy accumulations, anomalous moisture and
localized training profiles may produce isolated runoff concerns
within the area highlighted by the Marginal Risk.

Pereira

Day 2
Valid 12Z Sat Jul 18 2026 - 12Z Sun Jul 19 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM WEST TEXAS AND
SOUTHERN NEW MEXICO TO SOUTHERN UTAH, AND FROM THE NORTHERN MID-
ATLANTIC INTO SOUTHERN NEW YORK AND NEW ENGLAND...

...Western U.S.....
An expansive monsoonal convective pattern remains locked in place
across the Western CONUS, supporting the continuation of a broad
Slight Risk extending from West Texas and southern New Mexico
northwestward across central and northern Arizona into southern
Utah. An increase in low level moisture transport into the region,
coupled with the moisture already in place will support PW
anomalies 1.5-3 std dev above normal across much of this region.
This moisture will likely once again support widespread convective
development across the area. With ample daytime heating and
sufficient instability, these storms will be capable of producing
efficient rainfall rates. Given the history of recent
precipitation, soils have become increasingly sensitive across
portions of the region, elevating the potential for rapid runoff
and flash flooding concerns.

...Ohio Valley/Appalachians to the Mid Atlantic and Northeast...
A progressive cold front dropping southeastward will interact with
an anomalously moist airmass pooling ahead of it. Atmospheric
profiles will be highly favorable for efficient warm-rain
processes, featuring PWs over 2 inches and deep warm-cloud layers.
Where daytime heating and mid-70s dewpoints break capping
inversions, prefrontal convection will tap into greater instability
and raise rainfall rates.

This environment along with the concentration of urbanized areas
susceptible to fast runoff provided enough confidence to extend
the Slight Risk farther east from parts of eastern Pennsylvania and
northern New Jersey across southern New York and New England.
Limiting factors to highlighting a more widespread flash flooding
threat include fast storm moisture and lingering model discrepancy
regarding the exact placement of the heaviest precipitation axes.

Farther west through the central Appalachians into the Ohio Valley,
a broader Marginal Risk remains in place to cover what is
anticipated to be more isolated concerns.

Pereira

Day 3
Valid 12Z Sun Jul 19 2026 - 12Z Mon Jul 20 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
THE WESTERN U.S., FLORIDA GULF COAST, SOUTHEASTERN VIRGINIA AND
EASTERN NORTH CAROLINA...

...Western U.S....
The monsoon pattern will persist across the Western CONUS,
maintaining at least scattered convection from the West Texas, New
Mexico and Arizona into the Great Basin and Rockies. PW anomalies
of 2-3+ standard deviations will continue to center over portions
of the Great Basin. The higher areal average precipitation amounts
are expected to once again align along the Mogollon Rim into
southern Utah. Given the prior rainfall and moist soil conditions,
these areas will remain vulnerable to rapid runoff, with the
area's complex terrain and slot canyons raising localized concerns.
A broad Marginal Risk was maintained to highlight the daily
convective potential and runoff concerns.

...Florida Gulf Coast...
Deep tropical moisture and a slow-moving mid-to-upper level low
over the eastern Gulf will maintain a heavy rainfall threat.
Favorable low-level convergence along the eastern flank of the
system may produce heavy rainfall along Florida's West Coast. Some
models show the system lifting out to the north this period,
bringing the threat for heavy rain into the Big Bend region. A
Marginal Risk was maintained from the Tampa Bay area to the Big
Bend to highlight the potential for heavy rain along this area.

...Virginia Tidewater and Eastern North Carolina....
A cold front dropping out of the north is expected to slow across
this region, maintaining a deep moisture pool in advance. Pre-
frontal convergence and diurnal heating will likely produce pockets
of heavy, slow-moving thunderstorms prior to its passage. With
some differences in the details, model consensus continues to
indicate that 1-2 inch, with locally heavier amounts, are likely
within the Marginal Risk area, producing at least isolated concerns.
A targeted upgrade to a Slight may be required, especially if the
model consensus for heavy amounts begins to center across the more
vulnerable Tidewater region.

Pereira

Day 4 and Day 5

Valid 12Z Mon Jul 20 2026 - 12Z Wed Jul 22 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE NORTHEAST/MID ATLANTIC REGION...

...Western U.S...

A continuation of a traditional monsoonal pattern will continue
across the Western CONUS with scattered to widespread bouts of
locally heavy to excessive rainfall each day across much of the
Desert Southwest up through the Great Basin and into portions of
the Rockies. Deep moisture will be drawn northward around the
periphery of a building upper high extending from the Great Basin
to the Southern Plains. This sets up a well-defined axis of
elevated instability coupling with precipitable water anomalies
between +2 and +3 standard deviations above climatology for
July...with the strongest anomalies situated over Nevada and Utah.
QPF maxima are currently situated within the Mogollon Rim and
portions of southern Utah...both of which are the more susceptible
areas given the complex topography and slot canyons. Broad MRGL
risks exist for both days in similar locations outlining much of
the aforementioned area(s) above although short term upgrades in
spots are not our of the question.

...Florida...

Models continue to depict heavy rainfall across portions of the
northern Florida peninsula on Monday (Day 4) which spreads farther
northward in association with an area of low pressure. Ensemble
QPF for both periods indicate multiple inches of rain. This
continues to be a period to monitor for the prospects of this
being something becoming more organized than what the latest model
guidance indicates. For now, MRGL risks exist on both D4 and D5
for the threat of heavy rainfall.

Northeast US...

The deepening of a mid- and upper level trough by a digging upper
level jet will push a surface cold front into the Northeast US.
Deep moisture gets drawn northeastward ahead of the digging system
and should be in place as convection develops in vicinity of the
front. With such a moist environment and favorable low level
instability along with the upper support afforded by the
jet...downpours that lead to heavy or excessive rainfall amount are
possible.

Bann

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!_zXMH3-H1ZE4ARm4IEt-4tSMCfTBCnkUmbMg055EJLb0sARixd-MDwC4Z5Of6kAvHBmdz2ACXuALonPm855Rnz0iMZI$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!_zXMH3-H1ZE4ARm4IEt-4tSMCfTBCnkUmbMg055EJLb0sARixd-MDwC4Z5Of6kAvHBmdz2ACXuALonPm855RunqfK1A$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!_zXMH3-H1ZE4ARm4IEt-4tSMCfTBCnkUmbMg055EJLb0sARixd-MDwC4Z5Of6kAvHBmdz2ACXuALonPm855RIau3krE$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Fri Jul 17 19:50:42 2026

FOUS30 KWBC 171950
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
350 PM EDT Fri Jul 17 2026

Day 1
Valid 16Z Fri Jul 17 2026 - 12Z Sat Jul 18 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS MUCH OF WEST
TEXAS, SOUTHERN NEW MEXICO, ARIZONA, AND THE SOUTHERN GREAT
BASIN...

1600Z Update: There were 2 notable adjustments made to the Day 1
ERO, both within Slight Risk areas. The Slight Risk in western AZ
and far southeast NV was expanded westward a bit to include the Las
Vegas metro region, while the Slight across parts of Central TX was
expanded northward to include Abilene and areas east of Midland.
Both of these adjustments were based on current observational
trends (especially with the meso-enhanced vort lobe in TX), along
with the 12Z HREF and REFS QPF exceedance probabilities.

Hurley

Previous discussion...

...Western U.S....
A persistent monsoonal pattern will remain in place across the
West, supporting widespread convective coverage. Standardized
moisture anomalies of 2-3+ std dev extend from Arizona and
southern California to the northern Rockies, sustaining a broadly
unstable environment conducive to highly efficient rainfall.

A "high-end" Slight Risk remains centered along northern Arizona's
Mogollon Rim. The HREF and REFS guidance have remained consistent
in signaling the potential for localized amounts of 3+ inches in
this area, raising the potential for scattered to localized
significant flash flooding, especially given the already moist soil
conditions. Additionally, the Slight has been expanded eastward to
encompass portions of northeastern Arizona and northwestern New
Mexico, where HREF and REFS are also indicating the threat for
localized heavy amounts (2-3 inches).

Farther south and east, storms are expected to develop along the
Sacramento Mountains of southern New Mexico, threatening active
wildfire burn scars susceptible to rapid runoff.

...Texas...
Lingering mid-level energy over south-central Texas will slowly
track north and west on Friday. The overnight hi-res models
continued to suggest significantly less coverage of heavy amounts
than in previous days. However, remaining deep moisture, along
with a revitalized 30+ kt low level jet, will maintain at least a
localized threat for additional heavy rains and therefore a Slight
Risk covering much of Southwest to South-Central Texas was
maintained. Fortunately, the general consensus of the HREF and REFS
indicates the greater threat for heavy amounts will center west of
the areas most severely impacted earlier this week and closer to
the Davis Mountains today. Farther north, moisture and energy
lifting out will carry some potential for localized heavy rain and
perhaps isolated flash flooding into parts of Northwest Texas,
where a broad Marginal Risk was maintained.

...Western Florida...
A cut-off 500mb low lingering over the eastern Gulf will reside in
a favorable environment for highly-efficient rainfall (PWs at or
above 2 inches, MLCAPE over 1,000 J/kg, and deep warm-cloud
depths). This will easily support rainfall rates exceeding 3 in/hr.
Therefore, a Marginal Risk was maintained along portions of
Florida's West Coast, highlighting the potential for isolated
runoff concerns, especially in urbanized areas.

...Ohio/Tennessee Valley to the Central/Southern Appalachians...
A Marginal Risk was maintained as a broad, high-PW airmass
continues to spread north and east, with the expectation that
diurnally-driven storms may produce isolated, short-duration
runoff concerns this afternoon and evening.

...Northern Great Lakes...
A progressive upper trough and associated jet max diving into
northern Minnesota will initiate nocturnal convection from northern
Minnesota into Upper Michigan. While rapid storm motions should
limit widespread heavy accumulations, anomalous moisture and
localized training profiles may produce isolated runoff concerns
within the area highlighted by the Marginal Risk.

Pereira

Day 2
Valid 12Z Sat Jul 18 2026 - 12Z Sun Jul 19 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
THE FOUR CORNERS AND SOUTHWEST, AND ACROSS PARTS OF THE UPPER MID
ATLANTIC INTO SOUTHERN NEW YORK AND NEW ENGLAND...

2000 UTC Update: The most notable change to the Day 2 ERO was the
eastward and northward expansion of the Slight Risk area across
northeast AZ, southeast UT, central NM, and into southwest CO. The
expansion incorporates the Slot Canyons across southern UT, and was
supported by the high HREF and REFS probabilities (>50%) of hourly
rainfall rates of at least .50". Maximum FFG probabilities (40km
neighborhood probs) of the 1/3/6 hr FFG peak above 25% in these
areas per the 12Z HREF, while climb above 40% (over 70% in northern
AZ) per the 12Z REFS. Based on the 00Z guidance, and particularly
over UT, the ECMWF EFI does indicate spotty values over 0.7, with
shift- of- tails values < 1.0.

In addition, also based on the latest guidance/trends (particularly
the CAMs), have expanded the Slight Risk over the Northeast to
include more of CT, southern NY, eastern PA, much of NJ, and far
northern DE. Quite a few CAMs show spotty 3-5" totals ahead of the
mid/upper shortwave and associated surface cold front, with the 12Z
REFS showing 30-40% probabilities of >5.00" across CT-RI and
southern MA.

Hurley

Previous discussion..

...Western U.S.....
An expansive monsoonal convective pattern remains locked in place
across the Western CONUS, supporting the continuation of a broad
Slight Risk extending from West Texas and southern New Mexico
northwestward across central and northern Arizona into southern
Utah. An increase in low level moisture transport into the region,
coupled with the moisture already in place will support PW
anomalies 1.5-3 std dev above normal across much of this region.
This moisture will likely once again support widespread convective
development across the area. With ample daytime heating and
sufficient instability, these storms will be capable of producing
efficient rainfall rates. Given the history of recent
precipitation, soils have become increasingly sensitive across
portions of the region, elevating the potential for rapid runoff
and flash flooding concerns.

...Ohio Valley/Appalachians to the Mid Atlantic and Northeast...
A progressive cold front dropping southeastward will interact with
an anomalously moist airmass pooling ahead of it. Atmospheric
profiles will be highly favorable for efficient warm-rain
processes, featuring PWs over 2 inches and deep warm-cloud layers.
Where daytime heating and mid-70s dewpoints break capping
inversions, prefrontal convection will tap into greater instability
and raise rainfall rates.

This environment along with the concentration of urbanized areas
susceptible to fast runoff provided enough confidence to extend
the Slight Risk farther east from parts of eastern Pennsylvania and
northern New Jersey across southern New York and New England.
Limiting factors to highlighting a more widespread flash flooding
threat include fast storm moisture and lingering model discrepancy
regarding the exact placement of the heaviest precipitation axes.

Farther west through the central Appalachians into the Ohio Valley,
a broader Marginal Risk remains in place to cover what is
anticipated to be more isolated concerns.

...Florida Gulf Coast into Southeast Alabama and Southwest Georgia...
Deep tropical moisture and a slow-moving mid-to-upper level low
over the eastern Gulf will maintain a heavy rainfall threat, which
translates into the Day 3 ERO. Model QPFs have come up in this
area, now within the CAM windows, with high (>60%) probabilities of
24hr QPF exceeding 3" per both the 12Z HREF and REFS. Both are also
fairly bullish with the >5" probabilities west of the FL Big Bend
(30-40% per the HREF, 40-50% per the REFS).

Hurley/Pereira

Day 3
Valid 12Z Sun Jul 19 2026 - 12Z Mon Jul 20 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
THE WESTERN U.S., SOUTHEAST, AND LOWER MID ATLANTIC...

2000 UTC Update: Minor changes were made to the Day 3 ERO, based on
the latest (12Z) guidance suite. Per collaboration with WFO RAH,
felt that an expansion of the Marginal Risk area into central NC
and northeast SC was warranted. Have also expanded the Marginal
along the eastern Gulf Coast, while again nudging the western
periphery of the Marginal Risk to include more of southern NV
(including Las Vegas) and portions of southeast CA.

Not much change in the overall monsoonal pattern, though most of
the global guidance is a bit more diffuse with the heavier QPF
totals. Still think a Slight Risk will be likely somewhere,
probably very similar to the Slight Risk area on the current Day 2
ERO, but for now given the variance in the model QPFs, will keep
the Marginal Risk going and reassess with the next 1-2 forecast
cycles.

Hurley

Previous discussion...

...Western U.S....
The monsoon pattern will persist across the Western CONUS,
maintaining at least scattered convection from the West Texas, New
Mexico and Arizona into the Great Basin and Rockies. PW anomalies
of 2-3+ standard deviations will continue to center over portions
of the Great Basin. The higher areal average precipitation amounts
are expected to once again align along the Mogollon Rim into
southern Utah. Given the prior rainfall and moist soil conditions,
these areas will remain vulnerable to rapid runoff, with the
area's complex terrain and slot canyons raising localized concerns.
A broad Marginal Risk was maintained to highlight the daily
convective potential and runoff concerns.

...Florida Gulf Coast...
Deep tropical moisture and a slow-moving mid-to-upper level low
over the eastern Gulf will maintain a heavy rainfall threat.
Favorable low-level convergence along the eastern flank of the
system may produce heavy rainfall along Florida's West Coast. Some
models show the system lifting out to the north this period,
bringing the threat for heavy rain into the Big Bend region. A
Marginal Risk was maintained from the Tampa Bay area to the Big
Bend to highlight the potential for heavy rain along this area.

...Virginia Tidewater and Eastern North Carolina....
A cold front dropping out of the north is expected to slow across
this region, maintaining a deep moisture pool in advance. Pre-
frontal convergence and diurnal heating will likely produce pockets
of heavy, slow-moving thunderstorms prior to its passage. With
some differences in the details, model consensus continues to
indicate that 1-2 inch, with locally heavier amounts, are likely
within the Marginal Risk area, producing at least isolated concerns.
A targeted upgrade to a Slight may be required, especially if the
model consensus for heavy amounts begins to center across the more
vulnerable Tidewater region.

Pereira

Day 4 and Day 5

Valid 12Z Mon Jul 20 2026 - 12Z Wed Jul 22 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE NORTHEAST/MID ATLANTIC REGION AS WELL AS THE WESTERN US...

2030Z Discussion
Introduced a Marginal Risk area on Day 4 from the Great Lakes to
the Mid Atlantic region on Day 4 given a strengthening signal in
both the operational models and ensemble QPF guidance and the
magnitude of the moisture in place. Also made some minor
adjustments on Day 5 in the Northeast US and Mid-Atlantic region.
Maintained continuity in Florida and coastal Southeast US as an
area of low pressure tracks across the Florida peninsula. No change
needed in the West where weak and difficult-to-time shortwave
energy and anomalous moisture lingers on the western periphery of
an upper high in region of broad ridging.

Bann

Previous Discussion...

...Western U.S...

A continuation of a traditional monsoonal pattern will continue
across the Western CONUS with scattered to widespread bouts of
locally heavy to excessive rainfall each day across much of the
Desert Southwest up through the Great Basin and into portions of
the Rockies. Deep moisture will be drawn northward around the
periphery of a building upper high extending from the Great Basin
to the Southern Plains. This sets up a well-defined axis of
elevated instability coupling with precipitable water anomalies
between +2 and +3 standard deviations above climatology for
July...with the strongest anomalies situated over Nevada and Utah.
QPF maxima are currently situated within the Mogollon Rim and
portions of southern Utah...both of which are the more susceptible
areas given the complex topography and slot canyons. Broad MRGL
risks exist for both days in similar locations outlining much of
the aforementioned area(s) above although short term upgrades in
spots are not our of the question.

...Florida...

Models continue to depict heavy rainfall across portions of the
northern Florida peninsula on Monday (Day 4) which spreads farther
northward in association with an area of low pressure. Ensemble
QPF for both periods indicate multiple inches of rain. This
continues to be a period to monitor for the prospects of this
being something becoming more organized than what the latest model
guidance indicates. For now, MRGL risks exist on both D4 and D5
for the threat of heavy rainfall.

Northeast US...

The deepening of a mid- and upper level trough by a digging upper
level jet will push a surface cold front into the Northeast US.
Deep moisture gets drawn northeastward ahead of the digging system
and should be in place as convection develops in vicinity of the
front. With such a moist environment and favorable low level
instability along with the upper support afforded by the
jet...downpours that lead to heavy or excessive rainfall amount are
possible.

Bann

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!6MsgEfhfwyze6GL20Z3MUVz1tSBnbq0Ch-Kepqn8bA6BEwz0SMPRyJu33SN5G4t7PGulwb2_6i6h4K8yiCZAxAYBbVo$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!6MsgEfhfwyze6GL20Z3MUVz1tSBnbq0Ch-Kepqn8bA6BEwz0SMPRyJu33SN5G4t7PGulwb2_6i6h4K8yiCZAniVVTRU$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!6MsgEfhfwyze6GL20Z3MUVz1tSBnbq0Ch-Kepqn8bA6BEwz0SMPRyJu33SN5G4t7PGulwb2_6i6h4K8yiCZA8hjGGJI$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Jul 18 00:45:22 2026

FOUS30 KWBC 180044
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
844 PM EDT Fri Jul 17 2026

Day 1
Valid 01Z Sat Jul 18 2026 - 12Z Sat Jul 18 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS MUCH OF WEST
TEXAS, SOUTHERN NEW MEXICO, ARIZONA, AND THE SOUTHERN GREAT
BASIN...

0100Z Update...Only real change was the removal of the Marginal
Risk area in the Upper Peninsula of Michigan based on expected
forward speed of any convection that has yet to develop and the
lack of support from the HREF/RREF exceedance probabilities.
Otherwise, changes were more to adjust the boundaries of
previously-issued areas based on satellite or radar trends.

Bann

1600Z Update: There were 2 notable adjustments made to the Day 1
ERO, both within Slight Risk areas. The Slight Risk in western AZ
and far southeast NV was expanded westward a bit to include the Las
Vegas metro region, while the Slight across parts of Central TX was
expanded northward to include Abilene and areas east of Midland.
Both of these adjustments were based on current observational
trends (especially with the meso-enhanced vort lobe in TX), along
with the 12Z HREF and REFS QPF exceedance probabilities.

Hurley

Previous discussion...

...Western U.S....
A persistent monsoonal pattern will remain in place across the
West, supporting widespread convective coverage. Standardized
moisture anomalies of 2-3+ std dev extend from Arizona and
southern California to the northern Rockies, sustaining a broadly
unstable environment conducive to highly efficient rainfall.

A "high-end" Slight Risk remains centered along northern Arizona's
Mogollon Rim. The HREF and REFS guidance have remained consistent
in signaling the potential for localized amounts of 3+ inches in
this area, raising the potential for scattered to localized
significant flash flooding, especially given the already moist soil
conditions. Additionally, the Slight has been expanded eastward to
encompass portions of northeastern Arizona and northwestern New
Mexico, where HREF and REFS are also indicating the threat for
localized heavy amounts (2-3 inches).

Farther south and east, storms are expected to develop along the
Sacramento Mountains of southern New Mexico, threatening active
wildfire burn scars susceptible to rapid runoff.

...Texas...
Lingering mid-level energy over south-central Texas will slowly
track north and west on Friday. The overnight hi-res models
continued to suggest significantly less coverage of heavy amounts
than in previous days. However, remaining deep moisture, along
with a revitalized 30+ kt low level jet, will maintain at least a
localized threat for additional heavy rains and therefore a Slight
Risk covering much of Southwest to South-Central Texas was
maintained. Fortunately, the general consensus of the HREF and REFS
indicates the greater threat for heavy amounts will center west of
the areas most severely impacted earlier this week and closer to
the Davis Mountains today. Farther north, moisture and energy
lifting out will carry some potential for localized heavy rain and
perhaps isolated flash flooding into parts of Northwest Texas,
where a broad Marginal Risk was maintained.

...Western Florida...
A cut-off 500mb low lingering over the eastern Gulf will reside in
a favorable environment for highly-efficient rainfall (PWs at or
above 2 inches, MLCAPE over 1,000 J/kg, and deep warm-cloud
depths). This will easily support rainfall rates exceeding 3 in/hr.
Therefore, a Marginal Risk was maintained along portions of
Florida's West Coast, highlighting the potential for isolated
runoff concerns, especially in urbanized areas.

...Ohio/Tennessee Valley to the Central/Southern Appalachians...
A Marginal Risk was maintained as a broad, high-PW airmass
continues to spread north and east, with the expectation that
diurnally-driven storms may produce isolated, short-duration
runoff concerns this afternoon and evening.

...Northern Great Lakes...
A progressive upper trough and associated jet max diving into
northern Minnesota will initiate nocturnal convection from northern
Minnesota into Upper Michigan. While rapid storm motions should
limit widespread heavy accumulations, anomalous moisture and
localized training profiles may produce isolated runoff concerns
within the area highlighted by the Marginal Risk.

Pereira

Day 2
Valid 12Z Sat Jul 18 2026 - 12Z Sun Jul 19 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
THE FOUR CORNERS AND SOUTHWEST, AND ACROSS PARTS OF THE UPPER MID
ATLANTIC INTO SOUTHERN NEW YORK AND NEW ENGLAND...

2000 UTC Update: The most notable change to the Day 2 ERO was the
eastward and northward expansion of the Slight Risk area across
northeast AZ, southeast UT, central NM, and into southwest CO. The
expansion incorporates the Slot Canyons across southern UT, and was
supported by the high HREF and REFS probabilities (>50%) of hourly
rainfall rates of at least .50". Maximum FFG probabilities (40km
neighborhood probs) of the 1/3/6 hr FFG peak above 25% in these
areas per the 12Z HREF, while climb above 40% (over 70% in northern
AZ) per the 12Z REFS. Based on the 00Z guidance, and particularly
over UT, the ECMWF EFI does indicate spotty values over 0.7, with
shift- of- tails values < 1.0.

In addition, also based on the latest guidance/trends (particularly
the CAMs), have expanded the Slight Risk over the Northeast to
include more of CT, southern NY, eastern PA, much of NJ, and far
northern DE. Quite a few CAMs show spotty 3-5" totals ahead of the
mid/upper shortwave and associated surface cold front, with the 12Z
REFS showing 30-40% probabilities of >5.00" across CT-RI and
southern MA.

Hurley

Previous discussion..

...Western U.S.....
An expansive monsoonal convective pattern remains locked in place
across the Western CONUS, supporting the continuation of a broad
Slight Risk extending from West Texas and southern New Mexico
northwestward across central and northern Arizona into southern
Utah. An increase in low level moisture transport into the region,
coupled with the moisture already in place will support PW
anomalies 1.5-3 std dev above normal across much of this region.
This moisture will likely once again support widespread convective
development across the area. With ample daytime heating and
sufficient instability, these storms will be capable of producing
efficient rainfall rates. Given the history of recent
precipitation, soils have become increasingly sensitive across
portions of the region, elevating the potential for rapid runoff
and flash flooding concerns.

...Ohio Valley/Appalachians to the Mid Atlantic and Northeast...
A progressive cold front dropping southeastward will interact with
an anomalously moist airmass pooling ahead of it. Atmospheric
profiles will be highly favorable for efficient warm-rain
processes, featuring PWs over 2 inches and deep warm-cloud layers.
Where daytime heating and mid-70s dewpoints break capping
inversions, prefrontal convection will tap into greater instability
and raise rainfall rates.

This environment along with the concentration of urbanized areas
susceptible to fast runoff provided enough confidence to extend
the Slight Risk farther east from parts of eastern Pennsylvania and
northern New Jersey across southern New York and New England.
Limiting factors to highlighting a more widespread flash flooding
threat include fast storm moisture and lingering model discrepancy
regarding the exact placement of the heaviest precipitation axes.

Farther west through the central Appalachians into the Ohio Valley,
a broader Marginal Risk remains in place to cover what is
anticipated to be more isolated concerns.

...Florida Gulf Coast into Southeast Alabama and Southwest Georgia...
Deep tropical moisture and a slow-moving mid-to-upper level low
over the eastern Gulf will maintain a heavy rainfall threat, which
translates into the Day 3 ERO. Model QPFs have come up in this
area, now within the CAM windows, with high (>60%) probabilities of
24hr QPF exceeding 3" per both the 12Z HREF and REFS. Both are also
fairly bullish with the >5" probabilities west of the FL Big Bend
(30-40% per the HREF, 40-50% per the REFS).

Hurley/Pereira

Day 3
Valid 12Z Sun Jul 19 2026 - 12Z Mon Jul 20 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
THE WESTERN U.S., SOUTHEAST, AND LOWER MID ATLANTIC...

2000 UTC Update: Minor changes were made to the Day 3 ERO, based on
the latest (12Z) guidance suite. Per collaboration with WFO RAH,
felt that an expansion of the Marginal Risk area into central NC
and northeast SC was warranted. Have also expanded the Marginal
along the eastern Gulf Coast, while again nudging the western
periphery of the Marginal Risk to include more of southern NV
(including Las Vegas) and portions of southeast CA.

Not much change in the overall monsoonal pattern, though most of
the global guidance is a bit more diffuse with the heavier QPF
totals. Still think a Slight Risk will be likely somewhere,
probably very similar to the Slight Risk area on the current Day 2
ERO, but for now given the variance in the model QPFs, will keep
the Marginal Risk going and reassess with the next 1-2 forecast
cycles.

Hurley

Previous discussion...

...Western U.S....
The monsoon pattern will persist across the Western CONUS,
maintaining at least scattered convection from the West Texas, New
Mexico and Arizona into the Great Basin and Rockies. PW anomalies
of 2-3+ standard deviations will continue to center over portions
of the Great Basin. The higher areal average precipitation amounts
are expected to once again align along the Mogollon Rim into
southern Utah. Given the prior rainfall and moist soil conditions,
these areas will remain vulnerable to rapid runoff, with the
area's complex terrain and slot canyons raising localized concerns.
A broad Marginal Risk was maintained to highlight the daily
convective potential and runoff concerns.

...Florida Gulf Coast...
Deep tropical moisture and a slow-moving mid-to-upper level low
over the eastern Gulf will maintain a heavy rainfall threat.
Favorable low-level convergence along the eastern flank of the
system may produce heavy rainfall along Florida's West Coast. Some
models show the system lifting out to the north this period,
bringing the threat for heavy rain into the Big Bend region. A
Marginal Risk was maintained from the Tampa Bay area to the Big
Bend to highlight the potential for heavy rain along this area.

...Virginia Tidewater and Eastern North Carolina....
A cold front dropping out of the north is expected to slow across
this region, maintaining a deep moisture pool in advance. Pre-
frontal convergence and diurnal heating will likely produce pockets
of heavy, slow-moving thunderstorms prior to its passage. With
some differences in the details, model consensus continues to
indicate that 1-2 inch, with locally heavier amounts, are likely
within the Marginal Risk area, producing at least isolated concerns.
A targeted upgrade to a Slight may be required, especially if the
model consensus for heavy amounts begins to center across the more
vulnerable Tidewater region.

Pereira

Day 4 and Day 5

Valid 12Z Mon Jul 20 2026 - 12Z Wed Jul 22 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE NORTHEAST/MID ATLANTIC REGION AS WELL AS THE WESTERN US...

2030Z Discussion
Introduced a Marginal Risk area on Day 4 from the Great Lakes to
the Mid Atlantic region on Day 4 given a strengthening signal in
both the operational models and ensemble QPF guidance and the
magnitude of the moisture in place. Also made some minor
adjustments on Day 5 in the Northeast US and Mid-Atlantic region.
Maintained continuity in Florida and coastal Southeast US as an
area of low pressure tracks across the Florida peninsula. No change
needed in the West where weak and difficult-to-time shortwave
energy and anomalous moisture lingers on the western periphery of
an upper high in region of broad ridging.

Bann

Previous Discussion...

...Western U.S...

A continuation of a traditional monsoonal pattern will continue
across the Western CONUS with scattered to widespread bouts of
locally heavy to excessive rainfall each day across much of the
Desert Southwest up through the Great Basin and into portions of
the Rockies. Deep moisture will be drawn northward around the
periphery of a building upper high extending from the Great Basin
to the Southern Plains. This sets up a well-defined axis of
elevated instability coupling with precipitable water anomalies
between +2 and +3 standard deviations above climatology for
July...with the strongest anomalies situated over Nevada and Utah.
QPF maxima are currently situated within the Mogollon Rim and
portions of southern Utah...both of which are the more susceptible
areas given the complex topography and slot canyons. Broad MRGL
risks exist for both days in similar locations outlining much of
the aforementioned area(s) above although short term upgrades in
spots are not our of the question.

...Florida...

Models continue to depict heavy rainfall across portions of the
northern Florida peninsula on Monday (Day 4) which spreads farther
northward in association with an area of low pressure. Ensemble
QPF for both periods indicate multiple inches of rain. This
continues to be a period to monitor for the prospects of this
being something becoming more organized than what the latest model
guidance indicates. For now, MRGL risks exist on both D4 and D5
for the threat of heavy rainfall.

Northeast US...

The deepening of a mid- and upper level trough by a digging upper
level jet will push a surface cold front into the Northeast US.
Deep moisture gets drawn northeastward ahead of the digging system
and should be in place as convection develops in vicinity of the
front. With such a moist environment and favorable low level
instability along with the upper support afforded by the
jet...downpours that lead to heavy or excessive rainfall amount are
possible.

Bann

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!5hNRpsSV_SnxIYKPz9Z-UG9ZxlzvsEOIRoMMPe8HyM3cMmFukDm6ygzhiahmZbuusrBhZL6Q1A9l2ixVCMjwXOZ1SIE$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!5hNRpsSV_SnxIYKPz9Z-UG9ZxlzvsEOIRoMMPe8HyM3cMmFukDm6ygzhiahmZbuusrBhZL6Q1A9l2ixVCMjw-8GA73o$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!5hNRpsSV_SnxIYKPz9Z-UG9ZxlzvsEOIRoMMPe8HyM3cMmFukDm6ygzhiahmZbuusrBhZL6Q1A9l2ixVCMjwAtMFuoo$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Jul 18 08:35:12 2026

FOUS30 KWBC 180834
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
434 AM EDT Sat Jul 18 2026

Day 1
Valid 12Z Sat Jul 18 2026 - 12Z Sun Jul 19 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE SOUTHWEST, GREAT BASIN, WEST TEXAS, AND THE NORTHEAST...

...Western Texas to the Four Corners/Great Basin...
Overall, the forecast remains much the same, with mostly minor
spatial adjustments required based on the latest hi-res ensemble
guidance.

One of the bigger adjustments was a northward extension
of the Slight Risk across western Texas into the southern
Panhandle. This northern expansion was supported by a slow-moving
upper level shear axis combined with low-level southerly flow,
fueling notable moisture advection into that region. Both the HREF
and REFS guidance have trended more bullish, showing localized
potential for rainfall amounts exceeding 3 inches. These totals
will be capable of producing rapid runoff and localized flash
flooding, especially where soil conditions are more sensitive from
recent rainfall.

Farther west, the Slight Risk remains largely unchanged across
portions of New Mexico, Arizona, southern Utah, and southwestern
Colorado. This remains supported by high-moisture anomalies and
indication from the HREF and REFS for rainfall rates likely to
reach at least 0.5 in/hr in the stronger cells. The Mogollon Rim
looks to remain a focus storm initiation and for some of the higher
storm totals, with both the HREF and REFS showing high
probabilities for accumulations over 2 inches in that area. Recent
heavy rains across this area will likely make it more susceptible
to additional flash flooding.

...Midwest to the Mid Atlantic and Northeast...
A progressive cold front dropping southeastward is expected to
interact with an anomalously moist airmass pooling ahead it. While
the primary Slight Risk remains focused across parts of the
northern Mid Atlantic to southern New England, the broad western
shield of the Marginal Risk was expanded farther west across the
Ohio Valley and into northern Illinois. Within this area, a smaller
Slight Risk area was added over portions western Pennsylvania
where the latest HREF and REFS are indicating localized amounts of
2-3 inches are likely.

For the Slight Risk area over the northern Mid Atlantic and
Northeast, guidance shows two rounds of storms impacting portions
of eastern Pennsylvania, New Jersey eastward to southern New
England. A leading round of storms, well in advance of the front,
is expected to impact the region this afternoon, followed by a second
round accompanying the front itself during the overnight. Many of
the hi-res members suggest the heavier rainfall and potential flash
flooding threat will accompany the initial round, with the loss of
daytime heating and more stable air limiting the threat with the
second. With at least the first round, highly-efficient warm rain
processes and localized cell training may yield quick, short-
duration totals capable of producing isolated to scattered runoff
concerns, particularly in low-lying or urbanized areas. The Slight
Risk largely reflects the higher HREF probabilities for
accumulations of 3 inches or more.

...Florida Panhandle into Southeast Alabama and Southwest
Georgia...
Deep moisture spreading north ahead of a slow-moving mid-to-upper
level low will pool along a surface trough extending out of the
eastern Gulf. This moisture (PWs increasing to around 2 inches)
will fuel slow-moving storms developing by the late afternoon that
will be capable of producing heavy rates, which along with their
slow movement, may produce heavy amounts and isolated flash
flooding.

Pereira

Day 2
Valid 12Z Sun Jul 19 2026 - 12Z Mon Jul 20 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS THE
SOUTHWESTERN U.S. FROM WEST TEXAS TO SOUTHERN UTAH...

...Southwestern U.S....
The overall synoptic configuration remains largely unchanged from
the previous period, with a persistent monsoon pattern locked in
place -- keeping scattered to widespread convection in the forecast
from West Texas into the Great Basin and southern Rockies. Given
that PW anomalies remain notably high at 2-3 std dev above normal,
and soil conditions moist from prior rainfall, confidence was
sufficient to introduce a Slight Risk that extends from West Texas northeastward across southern New Mexico, central and northern
Arizona, into southern Utah.

An upper-level high centered over northern Utah and Colorado will
support steady easterly flow across the southern tier, effectively
tapping into and beginning to pull mid-level energy that has been
centered over West Texas along this deeper moisture axis. The
highest areal average precipitation amounts are expected to center
along the higher terrain, where slow-moving storms are expected to
develop with afternoon heating, before propagating off of the
terrain along convective outflows. Given sensitive, moist soil
conditions from successive days of widespread storms, much of this
area remains vulnerable to rapid runoff. Complex terrain, slot
canyons, and recent wildfire burn scars will further accentuate the
threat for flash flooding across parts of the region.

...Mid Mississippi Valley east to the Carolinas and south to the
Eastern Gulf Coast...
A more expansive Marginal Risk has been drawn for this period,
reflecting deep moisture atmospheric profiles and an increasing
potential for localized heavy rainfall amounts producing isolated
runoff concerns. This risk is centered along a cold front dropping
into North Carolina and the Tennessee Valley, while is begins to
slow over the lower Ohio and mid Mississippi valleys. Diurnal
heating and prefrontal convergence will tap into this moisture
pool, generating clusters of slow-moving efficient thunderstorms,
capable of producing 1-2 inch totals, with isolated higher amounts.
There remains a greater threat for more widespread heavier amounts
along the eastern extent of this area, centered over southeastern
Virginia and eastern North Carolina, where more defined upper
forcing will help accentuate the threat for amounts over 3 inches.

Additionally, the Marginal Risk has been extended southward down to
the Gulf Coast. This accounts for the deep tropical moisture
arriving ahead of the slow-moving disturbance lingering in the
eastern Gulf, as well as favorable low-level convergence focusing
along a slow-moving surface trough extending north from the Gulf.
Highly efficient warm-rain processes along these features will
maintain a threat for heavy, short-term duration totals and
isolated runoff concerns.

Pereira

Day 3
Valid 12Z Mon Jul 20 2026 - 12Z Tue Jul 21 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
ARIZONA AND NEW MEXICO...

...Southwest...
The primary adjustment for this forecast cycle is the introduction
of a Slight Risk across portions of New Mexico and Arizona. For
parts of the region, the setup remains much the same, with
anomalous moisture (2+ std dev above normal) supporting convective
activity and rainfall efficiency.

Mid-to-upper level energy/an inverted trough drifting east across
the region will provide larger-scale ascent to help better
organize monsoon convection. Furthermore, this feature will help
steer and push the convective and heavy rainfall threat a bit
farther west across portions of southeastern Arizona than in the
previous days. Given the combination of persistent anomalous
moisture, enhanced upper-level support, and sensitive soils,
expect localized rainfall rates to easily raise runoff concerns
across parts of the region. A surrounding broad Marginal Risk
remains in place extending up into the Great Basin and central
Rockies -- outlining the risk for less-organized storms, producing
isolated runoff concerns in those area.

...Upper Great Lakes...
A well-defined shortwave interacting with deepening moisture is
expected to produce strong storms capable of producing heavy
rainfall across the region. Guidance shows southwesterly to
easterly inflow supporting PWs increasing to around 2 inches. This
moisture along with strong ascent, afforded in part by favorable
upper jet dynamics, will fuel the potential for heavy rainfall-
producing storms. Training storms along the front may raise the
threat for heavy amounts and flash flooding concerns. Models differ
on the details, but there is some consensus for the heaviest
amounts centering from southern Wisconsin to northern Illinois,
where an upgrade to a Slight may be introduced in a future
issuance, if the trends hold.

...Eastern North Carolina...
A Marginal Risk was maintained where a front and coinciding pool of
deep moisture (PWs at or above 2 inches) are expected to linger,
extending the threat for heavy rainfall and possible flash flooding
into a second day.

...Florida Gulf Coast...
It remains uncertain how the disturbance in the eastern Gulf will
evolve and track. However, regardless of development, it is
expected that heavy rainfall will remain a threat for parts of the
Gulf Coast. Therefore, a Marginal Risk was maintained from the
Tampa Bay region to the Panhandle.

Pereira

Day 4 and Day 5
Valid 12Z Tue Jul 21 2026 - 12Z Thu Jul 23 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHWEST AS WELL AS THE CENTRAL APPALACHIANS ON TUESDAY...

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR EASTERN NORTH
CAROLINA AND SOUTHEASTERN VIRGINIA ON WEDNESDAY...

...Southwest...

The Southwest Monsoon will remain in full force across Arizona and
into Utah on Tuesday. Moisture anomalies especially to the north
across Utah could approach 5 sigma above normal for this time of
year, while into Arizona, PWATs to 2 inches will be a solid 3 sigma
above normal. With daytime heating, renewed rounds of thunderstorms
are expected to redevelop for the latest in the multi-afternoon
pattern. Soil moisture levels are already saturated over much of
Arizona and into southern Utah. Expect with the thermal low peaking
in intensity on Tuesday, that flash flooding concerns will become
more widespread as rains impact beyond the 4 Corners into Nevada,
Idaho, and Wyoming. A Slight Risk upgrade was introduced with this
update, and it's possible localized areas may see further upgrades
as Tuesday approaches. By Wednesday, ridging over the Southwest
will push the greater threats for thunderstorms further north into
the Intermountain West, with a low developing over the Plains
allowing for some of the moisture to overspread into portions of
the central Plains. The signal for heavy rain lessens on Wednesday,
so the threat drops to Marginal for now, though a Slight may be
needed into the Intermountain West with continued consistency in
the guidance.

...Central Appalachians...

A Slight Risk upgrade was also introduced for portions of the
Central Appalachians, particularly across West Virginia and into
southwest Pennsylvania. Abundant moisture across the Mid-Atlantic
will interact with a strong cold front pushing southwest across
Ohio during the afternoon. This will allow for numerous
thunderstorms to develop Tuesday afternoon. Upslope flow into the
flash flood prone mountains of West Virginia and Pennsylvania will
support additional thunderstorm development as compared with areas
further west where the front will clear the moisture, and further
east where there will be less forcing. PWATs approaching 2 inches
will also support storms capable of multiple inch per hour rainfall
rates, especially as they run into the mountains.

To the east across the Mid-Atlantic, moisture levels further
increase, with some areas perhaps reaching 2.25 inch PWATs Tuesday
afternoon. The forcing will be a bit more uncertain, but any storms
that form will be capable of very heavy rains. The I-95 corridor
from DC to NYC will have to be closely monitored as these heavily
populated and flood prone areas may have enough widespread activity
to need further upgrades.

...Tidewater of North Carolina and Virginia...

On Day 5/Wednesday, the same cold front that swings through the
Midwest, Northeast, and Mid-Atlantic on Tuesday slows down its
forward speed, perhaps even stalling to the west of the Tidewater
of North Carolina and Virginia. Plentiful tropical moisture
continues riding northeastward along that front, providing ample
opportunity for numerous training showers and thunderstorms to
develop over the region, likely moving out over the Atlantic off
Ocean City, Maryland and points north. Thus, the focus will be in
the highly urbanized Hampton Roads area, extending into much of the
coastal plain of North Carolina. Given the pretty impressive signal
for heavy rain, have started out the Day 5 ERO with a Slight Risk
in this region. There remains some uncertainty as to whether any
tropical development over the northeastern Gulf contributes to the
heavy rainfall expected in this region on Wednesday. Given the
signals for heavy rain expected Sunday/Monday over eastern North
Carolina, expect the soils by Wednesday to be significantly more
saturated than they are now, contributing to the heightened flash
flooding risk.

Wegman

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!7djHfDQGfH_oVV3iULmMeIvugdxoEw3sLxsfLKTK4ls3zM1xIU0gkZb7gGMSlFT6luS33_G6pO9LgR3JzxjNE0AEfcc$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!7djHfDQGfH_oVV3iULmMeIvugdxoEw3sLxsfLKTK4ls3zM1xIU0gkZb7gGMSlFT6luS33_G6pO9LgR3JzxjNLR4mIg0$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!7djHfDQGfH_oVV3iULmMeIvugdxoEw3sLxsfLKTK4ls3zM1xIU0gkZb7gGMSlFT6luS33_G6pO9LgR3JzxjN-sE8RgA$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Jul 18 16:01:10 2026

FOUS30 KWBC 181600
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1200 PM EDT Sat Jul 18 2026

Day 1
Valid 16Z Sat Jul 18 2026 - 12Z Sun Jul 19 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM PORTIONS OF
WEST TEXAS THROUGH THE EASTERN GREAT BASIN, AS WELL AS PARTS OF THE
NORTHEAST AND MID-ATLANTIC...

...Western Texas to the Four Corners/Great Basin...
Monsoon ridge will become favorably aligned to draw impressive
thermodynamics northward from Mexico, reaching from West Texas
through much of the Desert Southwest and then northward into the
Great Basin and Intermountain West. Multiple weak shortwaves
embedded within the flow will continue to progress anti-
cyclonically around this ridge, bringing locally enhanced ascent
to the region, with a few of these impulses noted on morning WV
imagery in TX and NM. While any of these impulses will locally
enhance ascent leading to clusters of more organized convection
today, the greatest risk is just the breadth of coverage of
thunderstorms with potentially heavy rainfall today.

PWs this morning are impressive across the region, measured via GPS
and morning RAOBs vary from around 1.2 inches at SLC to as high as
2.1 inches at PHX, at or above the 90th percentile across a large
area (and as high as +3 sigma), and that measured PW at PHX this
morning is a daily record. At the same time instability is progged
to climb to 1000-2000 J/kg, locally even higher, as far as 40N
latitude in the Four Corners, which is impressive and is a typical discriminator of more widespread monsoonal heavy rain/flash flood
days.

THe CAMs, including the UA WRF, are aggressive with coverage of
their simulated reflectivity across much of the area today, with
hourly rainfall potentially reaching 1.5 to 2.5 inches. This could
easily exceed the 1-hr FFG across the region, and in some areas the
3-hr FFG even has a high chance (40-60%) of being exceeded where
terrain-tying or boundary-collisions can cause a temporal extension
of the heavy rain rates. With storm motions generally expected to
be weak at 5-10 kts and chaotic, an active day is expected, with
scattered flash flooding expected, especially across vulnerable
features like burn scars, slot canyons, and urban areas.

The inherited SLGT risk was modified to account for recent
guidance, and there was some consideration of an increased risk
based on the impressive REFS exceedance probabilities which rise
above 55% for FFG, but the more muted HREF was used more heavily,
especially since the highest FFG exceedance is across the higher
elevations of the Mogollon Rim and not down into the deserts
(although an expansion SW into some lower terrain was made with
this update).

...Midwest to the Mid Atlantic and Northeast...
A cold front will drop steadily southeast from the Great Lakes,
reaching the lower Ohio Valley and the Mid-Atlantic by Sunday
morning. Ahead of this front, impressive moisture will pool from
Kentucky eastward to Long Island and Cape Cod, where PWs are
already 1.75 to 2.0 inches and will climb above 2.0 inches through
this aftn. The overlap of this elevated PW with increasing SBCAPE
(2000-3000 J/kg forecast) will create robust thermodynamics which
will support widespread convection capable of producing intense
hourly rainfall for which the HREF and REFS suggest has a 40-60%
(10-15% chance) of exceeding 1 inch (2 inches).

The excessive rainfall risk will steadily increase through the aftn
and continue into this evening/tonight as multiple rounds of
thunderstorms develop and track across the area. 0-6km bulk shear is
progged to increase to 30-40 kts ahead of the cold front, and as
weak impulses move west to east from the Ohio Valley into the Mid-
Atlantic, this will allow for some organization into clusters
tracking parallel to the front (and pre-frontal trough). Ahead of
the front, the Corfidi vectors and mean flow will align from the
west, leading to an increased backbuilding potential into the
higher thermodynamics with cells then tracking across the same
areas of the Mid-Atlantic states and into southern New England.
This will occur ahead of the front which will produce a second
round of heavy rainfall potential, albeit with more progressive NW
to SE motion to the cells.

The inherited SLGT risk has been adjusted to account for new
guidance, and due to elevated probabilities from both the HREF and
REFS (40-60% for 3"/24hrs, 10-15% for 5"/24hrs) atop sensitive
areas due to urban development and recent rainfall producing compromised
FFG. This included connecting the SLGT risks across PA where the
ARW guidance is most aggressive and there is sufficient potential
for some training (or meso-cyclones to enhance rainfall rates) to
include a larger area. Considered an elevated internal SLGT risk
for the Tri-State area as well, but enough uncertainty in position
and timing of redevelopment after CAPE exhaustion this morning
prevented that category increase.

...Florida Panhandle through Southwest Georgia...
Deep moisture spreading north ahead of a slow-moving mid-to-upper
level low will pool along a surface trough extending out of the
eastern Gulf. This moisture (PWs increasing to above 2 inches)
will fuel slow-moving storms as Corfidi vectors become aligned
anti-parallel to weak 0-6km mean winds of just 5-10 kts. With rain
rates possibly (20-40%) exceeding 2"/hr at times this could create
at least isolated instances of excessive rainfall leading to flash
flooding.

...Western Florida Peninsula...
A convective MCV positioned west of the Florida Panhandle across
the northeast Gulf will drift westward today within a pool of
tropical PWs nearing 2.25 inches. As this feature drifts slowly
westward, it has, at least this morning, temporarily stalled inflow
along the Florida west coast between Naples and Fort Meyers. The
high-res CAMs are not extremely aggressive with rainfall today,
but have been under-forecasting the current activity (MRMS already
2-4" in some areas with hourly rain rates of 2-3"). If this band
continues to stall, continued impressive rainfall rates are likely,
and the recent RRFS, HRRR, and some of the experimental REFS
members show an additional 2-4" of rain are possible. This has
resulted in a narrow MRGL risk addition which aligns well with
recently issued MPD #764.

Weiss

Day 2
Valid 12Z Sun Jul 19 2026 - 12Z Mon Jul 20 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS THE
SOUTHWESTERN U.S. FROM WEST TEXAS TO SOUTHERN UTAH...

...Southwestern U.S....
The overall synoptic configuration remains largely unchanged from
the previous period, with a persistent monsoon pattern locked in
place -- keeping scattered to widespread convection in the forecast
from West Texas into the Great Basin and southern Rockies. Given
that PW anomalies remain notably high at 2-3 std dev above normal,
and soil conditions moist from prior rainfall, confidence was
sufficient to introduce a Slight Risk that extends from West Texas northeastward across southern New Mexico, central and northern
Arizona, into southern Utah.

An upper-level high centered over northern Utah and Colorado will
support steady easterly flow across the southern tier, effectively
tapping into and beginning to pull mid-level energy that has been
centered over West Texas along this deeper moisture axis. The
highest areal average precipitation amounts are expected to center
along the higher terrain, where slow-moving storms are expected to
develop with afternoon heating, before propagating off of the
terrain along convective outflows. Given sensitive, moist soil
conditions from successive days of widespread storms, much of this
area remains vulnerable to rapid runoff. Complex terrain, slot
canyons, and recent wildfire burn scars will further accentuate the
threat for flash flooding across parts of the region.

...Mid Mississippi Valley east to the Carolinas and south to the
Eastern Gulf Coast...
A more expansive Marginal Risk has been drawn for this period,
reflecting deep moisture atmospheric profiles and an increasing
potential for localized heavy rainfall amounts producing isolated
runoff concerns. This risk is centered along a cold front dropping
into North Carolina and the Tennessee Valley, while is begins to
slow over the lower Ohio and mid Mississippi valleys. Diurnal
heating and prefrontal convergence will tap into this moisture
pool, generating clusters of slow-moving efficient thunderstorms,
capable of producing 1-2 inch totals, with isolated higher amounts.
There remains a greater threat for more widespread heavier amounts
along the eastern extent of this area, centered over southeastern
Virginia and eastern North Carolina, where more defined upper
forcing will help accentuate the threat for amounts over 3 inches.

Additionally, the Marginal Risk has been extended southward down to
the Gulf Coast. This accounts for the deep tropical moisture
arriving ahead of the slow-moving disturbance lingering in the
eastern Gulf, as well as favorable low-level convergence focusing
along a slow-moving surface trough extending north from the Gulf.
Highly efficient warm-rain processes along these features will
maintain a threat for heavy, short-term duration totals and
isolated runoff concerns.

Pereira

Day 3
Valid 12Z Mon Jul 20 2026 - 12Z Tue Jul 21 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
ARIZONA AND NEW MEXICO...

...Southwest...
The primary adjustment for this forecast cycle is the introduction
of a Slight Risk across portions of New Mexico and Arizona. For
parts of the region, the setup remains much the same, with
anomalous moisture (2+ std dev above normal) supporting convective
activity and rainfall efficiency.

Mid-to-upper level energy/an inverted trough drifting east across
the region will provide larger-scale ascent to help better
organize monsoon convection. Furthermore, this feature will help
steer and push the convective and heavy rainfall threat a bit
farther west across portions of southeastern Arizona than in the
previous days. Given the combination of persistent anomalous
moisture, enhanced upper-level support, and sensitive soils,
expect localized rainfall rates to easily raise runoff concerns
across parts of the region. A surrounding broad Marginal Risk
remains in place extending up into the Great Basin and central
Rockies -- outlining the risk for less-organized storms, producing
isolated runoff concerns in those area.

...Upper Great Lakes...
A well-defined shortwave interacting with deepening moisture is
expected to produce strong storms capable of producing heavy
rainfall across the region. Guidance shows southwesterly to
easterly inflow supporting PWs increasing to around 2 inches. This
moisture along with strong ascent, afforded in part by favorable
upper jet dynamics, will fuel the potential for heavy rainfall-
producing storms. Training storms along the front may raise the
threat for heavy amounts and flash flooding concerns. Models differ
on the details, but there is some consensus for the heaviest
amounts centering from southern Wisconsin to northern Illinois,
where an upgrade to a Slight may be introduced in a future
issuance, if the trends hold.

...Eastern North Carolina...
A Marginal Risk was maintained where a front and coinciding pool of
deep moisture (PWs at or above 2 inches) are expected to linger,
extending the threat for heavy rainfall and possible flash flooding
into a second day.

...Florida Gulf Coast...
It remains uncertain how the disturbance in the eastern Gulf will
evolve and track. However, regardless of development, it is
expected that heavy rainfall will remain a threat for parts of the
Gulf Coast. Therefore, a Marginal Risk was maintained from the
Tampa Bay region to the Panhandle.

Pereira

Day 4 and Day 5
Valid 12Z Tue Jul 21 2026 - 12Z Thu Jul 23 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHWEST AS WELL AS THE CENTRAL APPALACHIANS ON TUESDAY...

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR EASTERN NORTH
CAROLINA AND SOUTHEASTERN VIRGINIA ON WEDNESDAY...

...Southwest...

The Southwest Monsoon will remain in full force across Arizona and
into Utah on Tuesday. Moisture anomalies especially to the north
across Utah could approach 5 sigma above normal for this time of
year, while into Arizona, PWATs to 2 inches will be a solid 3 sigma
above normal. With daytime heating, renewed rounds of thunderstorms
are expected to redevelop for the latest in the multi-afternoon
pattern. Soil moisture levels are already saturated over much of
Arizona and into southern Utah. Expect with the thermal low peaking
in intensity on Tuesday, that flash flooding concerns will become
more widespread as rains impact beyond the 4 Corners into Nevada,
Idaho, and Wyoming. A Slight Risk upgrade was introduced with this
update, and it's possible localized areas may see further upgrades
as Tuesday approaches. By Wednesday, ridging over the Southwest
will push the greater threats for thunderstorms further north into
the Intermountain West, with a low developing over the Plains
allowing for some of the moisture to overspread into portions of
the central Plains. The signal for heavy rain lessens on Wednesday,
so the threat drops to Marginal for now, though a Slight may be
needed into the Intermountain West with continued consistency in
the guidance.

...Central Appalachians...

A Slight Risk upgrade was also introduced for portions of the
Central Appalachians, particularly across West Virginia and into
southwest Pennsylvania. Abundant moisture across the Mid-Atlantic
will interact with a strong cold front pushing southwest across
Ohio during the afternoon. This will allow for numerous
thunderstorms to develop Tuesday afternoon. Upslope flow into the
flash flood prone mountains of West Virginia and Pennsylvania will
support additional thunderstorm development as compared with areas
further west where the front will clear the moisture, and further
east where there will be less forcing. PWATs approaching 2 inches
will also support storms capable of multiple inch per hour rainfall
rates, especially as they run into the mountains.

To the east across the Mid-Atlantic, moisture levels further
increase, with some areas perhaps reaching 2.25 inch PWATs Tuesday
afternoon. The forcing will be a bit more uncertain, but any storms
that form will be capable of very heavy rains. The I-95 corridor
from DC to NYC will have to be closely monitored as these heavily
populated and flood prone areas may have enough widespread activity
to need further upgrades.

...Tidewater of North Carolina and Virginia...

On Day 5/Wednesday, the same cold front that swings through the
Midwest, Northeast, and Mid-Atlantic on Tuesday slows down its
forward speed, perhaps even stalling to the west of the Tidewater
of North Carolina and Virginia. Plentiful tropical moisture
continues riding northeastward along that front, providing ample
opportunity for numerous training showers and thunderstorms to
develop over the region, likely moving out over the Atlantic off
Ocean City, Maryland and points north. Thus, the focus will be in
the highly urbanized Hampton Roads area, extending into much of the
coastal plain of North Carolina. Given the pretty impressive signal
for heavy rain, have started out the Day 5 ERO with a Slight Risk
in this region. There remains some uncertainty as to whether any
tropical development over the northeastern Gulf contributes to the
heavy rainfall expected in this region on Wednesday. Given the
signals for heavy rain expected Sunday/Monday over eastern North
Carolina, expect the soils by Wednesday to be significantly more
saturated than they are now, contributing to the heightened flash
flooding risk.

Wegman

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!-FNTNwmN11zByrP7Srk2nfYqtfFDD9Q1c5-qIiuIYvQoD9nJ4xiNPPNuzZqU5ot6m-FZu4w_z71l5FyWnSD_em5kGlk$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!-FNTNwmN11zByrP7Srk2nfYqtfFDD9Q1c5-qIiuIYvQoD9nJ4xiNPPNuzZqU5ot6m-FZu4w_z71l5FyWnSD_IA1DHnY$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!-FNTNwmN11zByrP7Srk2nfYqtfFDD9Q1c5-qIiuIYvQoD9nJ4xiNPPNuzZqU5ot6m-FZu4w_z71l5FyWnSD_bLrhDwY$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Jul 18 19:07:04 2026

FOUS30 KWBC 181906
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
306 PM EDT Sat Jul 18 2026

Day 1
Valid 16Z Sat Jul 18 2026 - 12Z Sun Jul 19 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM PORTIONS OF
WEST TEXAS THROUGH THE EASTERN GREAT BASIN, AS WELL AS PARTS OF THE
NORTHEAST AND MID-ATLANTIC...

...Western Texas to the Four Corners/Great Basin...
Monsoon ridge will become favorably aligned to draw impressive
thermodynamics northward from Mexico, reaching from West Texas
through much of the Desert Southwest and then northward into the
Great Basin and Intermountain West. Multiple weak shortwaves
embedded within the flow will continue to progress anti-
cyclonically around this ridge, bringing locally enhanced ascent
to the region, with a few of these impulses noted on morning WV
imagery in TX and NM. While any of these impulses will locally
enhance ascent leading to clusters of more organized convection
today, the greatest risk is just the breadth of coverage of
thunderstorms with potentially heavy rainfall today.

PWs this morning are impressive across the region, measured via GPS
and morning RAOBs vary from around 1.2 inches at SLC to as high as
2.1 inches at PHX, at or above the 90th percentile across a large
area (and as high as +3 sigma), and that measured PW at PHX this
morning is a daily record. At the same time instability is progged
to climb to 1000-2000 J/kg, locally even higher, as far as 40N
latitude in the Four Corners, which is impressive and is a typical discriminator of more widespread monsoonal heavy rain/flash flood
days.

THe CAMs, including the UA WRF, are aggressive with coverage of
their simulated reflectivity across much of the area today, with
hourly rainfall potentially reaching 1.5 to 2.5 inches. This could
easily exceed the 1-hr FFG across the region, and in some areas the
3-hr FFG even has a high chance (40-60%) of being exceeded where
terrain-tying or boundary-collisions can cause a temporal extension
of the heavy rain rates. With storm motions generally expected to
be weak at 5-10 kts and chaotic, an active day is expected, with
scattered flash flooding expected, especially across vulnerable
features like burn scars, slot canyons, and urban areas.

The inherited SLGT risk was modified to account for recent
guidance, and there was some consideration of an increased risk
based on the impressive REFS exceedance probabilities which rise
above 55% for FFG, but the more muted HREF was used more heavily,
especially since the highest FFG exceedance is across the higher
elevations of the Mogollon Rim and not down into the deserts
(although an expansion SW into some lower terrain was made with
this update).

...Midwest to the Mid Atlantic and Northeast...
A cold front will drop steadily southeast from the Great Lakes,
reaching the lower Ohio Valley and the Mid-Atlantic by Sunday
morning. Ahead of this front, impressive moisture will pool from
Kentucky eastward to Long Island and Cape Cod, where PWs are
already 1.75 to 2.0 inches and will climb above 2.0 inches through
this aftn. The overlap of this elevated PW with increasing SBCAPE
(2000-3000 J/kg forecast) will create robust thermodynamics which
will support widespread convection capable of producing intense
hourly rainfall for which the HREF and REFS suggest has a 40-60%
(10-15% chance) of exceeding 1 inch (2 inches).

The excessive rainfall risk will steadily increase through the aftn
and continue into this evening/tonight as multiple rounds of
thunderstorms develop and track across the area. 0-6km bulk shear is
progged to increase to 30-40 kts ahead of the cold front, and as
weak impulses move west to east from the Ohio Valley into the Mid-
Atlantic, this will allow for some organization into clusters
tracking parallel to the front (and pre-frontal trough). Ahead of
the front, the Corfidi vectors and mean flow will align from the
west, leading to an increased backbuilding potential into the
higher thermodynamics with cells then tracking across the same
areas of the Mid-Atlantic states and into southern New England.
This will occur ahead of the front which will produce a second
round of heavy rainfall potential, albeit with more progressive NW
to SE motion to the cells.

The inherited SLGT risk has been adjusted to account for new
guidance, and due to elevated probabilities from both the HREF and
REFS (40-60% for 3"/24hrs, 10-15% for 5"/24hrs) atop sensitive
areas due to urban development and recent rainfall producing compromised
FFG. This included connecting the SLGT risks across PA where the
ARW guidance is most aggressive and there is sufficient potential
for some training (or meso-cyclones to enhance rainfall rates) to
include a larger area. Considered an elevated internal SLGT risk
for the Tri-State area as well, but enough uncertainty in position
and timing of redevelopment after CAPE exhaustion this morning
prevented that category increase.

...Florida Panhandle through Southwest Georgia...
Deep moisture spreading north ahead of a slow-moving mid-to-upper
level low will pool along a surface trough extending out of the
eastern Gulf. This moisture (PWs increasing to above 2 inches)
will fuel slow-moving storms as Corfidi vectors become aligned
anti-parallel to weak 0-6km mean winds of just 5-10 kts. With rain
rates possibly (20-40%) exceeding 2"/hr at times this could create
at least isolated instances of excessive rainfall leading to flash
flooding.

...Western Florida Peninsula...
A convective MCV positioned west of the Florida Panhandle across
the northeast Gulf will drift westward today within a pool of
tropical PWs nearing 2.25 inches. As this feature drifts slowly
westward, it has, at least this morning, temporarily stalled inflow
along the Florida west coast between Naples and Fort Meyers. The
high-res CAMs are not extremely aggressive with rainfall today,
but have been under-forecasting the current activity (MRMS already
2-4" in some areas with hourly rain rates of 2-3"). If this band
continues to stall, continued impressive rainfall rates are likely,
and the recent RRFS, HRRR, and some of the experimental REFS
members show an additional 2-4" of rain are possible. This has
resulted in a narrow MRGL risk addition which aligns well with
recently issued MPD #764.

Weiss

Day 2
Valid 12Z Sun Jul 19 2026 - 12Z Mon Jul 20 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS THE
SOUTHWESTERN U.S. FROM WEST TEXAS TO SOUTHERN UTAH, AS WELL AS
PORTIONS OF NORTH CAROLINA...

...Southwestern U.S....
The monsoon ridge will persist in a favorable alignment Sunday,
keeping the overall synoptic pattern relatively unchanged from D1.
This will create another day of scattered to widespread convection
from the Desert Southwest, through West Texas, and northward into
the Great Basin and Intermountain West. The primary different
between the synoptic pattern Saturday vs Sunday may be just a
subtle reorganization of the ridge center near the WY/CO border,
which could allow for a subtly farther NW shift of thunderstorm
activity than what occurs Saturday.

Regardless, the environment will support another active day, and
with PWs reaching +2 to +3 sigma (a plume of 0.75" north to 1.75"
south) overlapping widespread MUCAPE of 250-1000 J/kg, this will
support heavy rainfall rates within any of the convection on
Sunday. HREF and REFS neighborhood probabilities indicate a 60-80%
chance of hourly rainfall to 1", with locally 2"/hr rates also
possible (10-20%). Although bulk shear is expected to remain
modest, up to 20 kts, suggesting primarily pulse type convection,
weak 0-6km mean winds and Corfidi vectors will allow for storm
mergers and boundary interactions to cause chaotic and slow
motions, with subtle terrain tying or boundary stalling storms
developing at times. This will create locally 3-4" of rain,
especially from the Mogollon Rim southeast into West Texas where
higher MUCAPE is progged. However, anywhere these slow storms
develop with the intense rain rates, instances of flash flooding
will be possible, especially atop sensitive terrain features like
slot canyons and dry washes, or over burn scars and urban areas.

Once again, the probabilities indicate the heaviest rainfall will
occur in the higher terrain, but light E/NE flow and outflows could
help storms dive off the terrain into the lower deserts at times as
well.

...Mid-Mississippi Valley through the Carolinas...
After coordination with the eastern NC WFOs, a targeted SLGT risk
has been added for eastern NC embedded within the broader MRGL
extending from the Mid-Mississippi Valley through the Tennessee
Valley and into the southern Mid-Atlanic states. This area will see
scattered to widespread thunderstorm development along and ahead of
a cold front which will slowly drop southward through the day. The
downstream environment will be extremely supportive of heavy rain
thanks to PWs of 2-2.25 inches overlapped with MUCAPE above 2000
J/kg.

While much of the convection will be of the pulse variety, some
increasing bulk shear reaching 25-35 kts, especially late across NC
and the Mid-Mississippi Valley could help organize storms into
clusters, which will then move parallel to the boundary to support
prolonged periods of training. With rainfall rates of 2"/hr or
more, this could cause locally more than 3" of rain, with a 20-40%
chance of at least 5" across eastern NC where a shortwave will help
spawn a wave of low pressure to improve ascent and organize
thunderstorm activity.

...Eastern Gulf Coast...
A tropical disturbance (AL91) for which NHC has a 40% of
development over the next 7 days in the northeastern Gulf will
spread at least moderate rainfall onshore the west coast of Florida
through the Panhandle and potentially as far east as eastern
Louisiana. While there is considerable uncertainty into the onshore
extent of QPF on D2, the HREF and REFS both suggest a 20-40% chance
of at least 3" of rainfall along the coast, driving the adjustments
to the inherited MRGL risk.

...Upper Mississippi Valley...
A shortwave embedded within squeezed mid-level flow will crest the
Four-Corners ridge and then dive southeast Sunday evening/night
into the Northern Plains and Upper Midwest. This shortwave will
interact with a frontal system to enhance ascent, with a wave of
low pressure potentially also developing. As the LLJ develops
within the accompanying warm sector, it is progged to accelerate to
25-35 kts, drawing robust thermodynamics (PWs above 2" with MUCAPE
over 3000 J/kg) northward and isentropically ascending the NW to SE
oriented warm front. This will help spawn thunderstorms during the
evening, with backbuilding/training possible from the eastern
Dakotas into southern Minnesota. The HREF and REFS probabilities
suggest a 15-25% chance for at least 3" of rainfall thanks to
training 1-2"/hr rain rates, so a MRGL risk was added for at least
localized flash flood potential.

Weiss

Day 3
Valid 12Z Mon Jul 20 2026 - 12Z Tue Jul 21 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
ARIZONA AND NEW MEXICO...

...Southwest...
Changes from inherited were primarily cosmetic to account for new
guidance, but another day of active (although with somewhat less
coverage than the weekend) monsoonal convection is expected. This
is due to a generally unchanged synoptic pattern with anomalous
moisture supporting convective activity and rainfall efficiency.

South of the ridge, as in the previous few days, shortwaves
rotating westward will help steer and enhance convective coverage,
and where this overlaps with the greatest instability/PW across
NM/AZ should receive the greatest coverage of thunderstorms with
flash flood potential. There is some concern that instability may
struggle to return Monday due to widespread convective coverage and
residual cloud cover Sunday night, which may necessitate
additional adjustments to the risk area, but at this time it still
appears there will be another day of scattered to widespread
convection with at least scattered flash flood instances. This will
be most likely across vulnerable features such as dry washes, burn
scars, and slot canyons.

...Great Lakes...
A well-defined shortwave interacting with deepening moisture is
expected to produce strong storms capable of producing heavy
rainfall across the region. Locally backed and accelerated low-
level flow will help surge PWs to 2 inches or more, especially
within a progressive warm sector progged to race across the region
during D3. This moisture, along with strong ascent driven both by
low-level isentropic ascent and favorable upper jet dynamics, will
fuel the potential for heavy rainfall-producing storms. Increasing
bulk shear to 30-50 kts will help organize convection into clusters
or supercells, raising the potential for intense rain rates of
1-2"/hr, through which any short-term training could enhance the
flood risk. At this time storms may move rapidly enough to preclude
a higher risk, but will continue to monitor for a possible targeted
upgrade to a SLGT risk with later issuances.

...North Carolina/Southern Virginia...
A Marginal Risk was maintained where a front and coinciding pool
of deep moisture (PWs at or above 2 inches) are expected to linger,
extending the threat for heavy rainfall and possible flash
flooding into a second day. There is some potential a SLGT risk may
be needed here as well, but that risk will be somewhat dependent on
what occurs D2, so after coordination with the WFOs, opted to
maintain the MRGL for now and reassess as the event gets closer.

...Florida Gulf Coast...
Considerable uncertainty remains regarding AL91 in the northern
Gulf. There will continue to be at least a low-end risk for heavy
rainfall around this system as tropical moisture streams northward
to the FL Panhandle and surrounding areas. At this time the MRGL
risk was maintained and only cosmetically adjusted, but future
refinements are expected as this system becomes more organized.

Weiss

Day 4 and Day 5

Valid 12Z Tue Jul 21 2026 - 12Z Thu Jul 23 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHWEST AS WELL AS THE CENTRAL APPALACHIANS ON TUESDAY...

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR EASTERN NORTH
CAROLINA AND SOUTHEASTERN VIRGINIA ON WEDNESDAY...

2030Z Discussion...
Few changes needed to either the excessive risk in the eastern US
or the western states. The 12Z model QPF and the ensemble guidance
still aligned fairly closely with previous runs...so changes to the
Day 4/5 ERO were minor adjustments rather than a shift in the
overall forecast reasoning,

Bann

Previous Discussion...

...Southwest...

The Southwest Monsoon will remain in full force across Arizona and
into Utah on Tuesday. Moisture anomalies especially to the north
across Utah could approach 5 sigma above normal for this time of
year, while into Arizona, PWATs to 2 inches will be a solid 3 sigma
above normal. With daytime heating, renewed rounds of thunderstorms
are expected to redevelop for the latest in the multi-afternoon
pattern. Soil moisture levels are already saturated over much of
Arizona and into southern Utah. Expect with the thermal low peaking
in intensity on Tuesday, that flash flooding concerns will become
more widespread as rains impact beyond the 4 Corners into Nevada,
Idaho, and Wyoming. A Slight Risk upgrade was introduced with this
update, and it's possible localized areas may see further upgrades
as Tuesday approaches. By Wednesday, ridging over the Southwest
will push the greater threats for thunderstorms further north into
the Intermountain West, with a low developing over the Plains
allowing for some of the moisture to overspread into portions of
the central Plains. The signal for heavy rain lessens on Wednesday,
so the threat drops to Marginal for now, though a Slight may be
needed into the Intermountain West with continued consistency in
the guidance.

...Central Appalachians...

A Slight Risk upgrade was also introduced for portions of the
Central Appalachians, particularly across West Virginia and into
southwest Pennsylvania. Abundant moisture across the Mid-Atlantic
will interact with a strong cold front pushing southwest across
Ohio during the afternoon. This will allow for numerous
thunderstorms to develop Tuesday afternoon. Upslope flow into the
flash flood prone mountains of West Virginia and Pennsylvania will
support additional thunderstorm development as compared with areas
further west where the front will clear the moisture, and further
east where there will be less forcing. PWATs approaching 2 inches
will also support storms capable of multiple inch per hour rainfall
rates, especially as they run into the mountains.

To the east across the Mid-Atlantic, moisture levels further
increase, with some areas perhaps reaching 2.25 inch PWATs Tuesday
afternoon. The forcing will be a bit more uncertain, but any storms
that form will be capable of very heavy rains. The I-95 corridor
from DC to NYC will have to be closely monitored as these heavily
populated and flood prone areas may have enough widespread activity
to need further upgrades.

...Tidewater of North Carolina and Virginia...

On Day 5/Wednesday, the same cold front that swings through the
Midwest, Northeast, and Mid-Atlantic on Tuesday slows down its
forward speed, perhaps even stalling to the west of the Tidewater
of North Carolina and Virginia. Plentiful tropical moisture
continues riding northeastward along that front, providing ample
opportunity for numerous training showers and thunderstorms to
develop over the region, likely moving out over the Atlantic off
Ocean City, Maryland and points north. Thus, the focus will be in
the highly urbanized Hampton Roads area, extending into much of the
coastal plain of North Carolina. Given the pretty impressive signal
for heavy rain, have started out the Day 5 ERO with a Slight Risk
in this region. There remains some uncertainty as to whether any
tropical development over the northeastern Gulf contributes to the
heavy rainfall expected in this region on Wednesday. Given the
signals for heavy rain expected Sunday/Monday over eastern North
Carolina, expect the soils by Wednesday to be significantly more
saturated than they are now, contributing to the heightened flash
flooding risk.

Wegman

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!_D8UGe5WivvDmk7lBZ_AxTnqwiUR1JDUe1FoePjcRFSY_fCVcLXvESrv_mRJodeLZxW7nqjFN7Bc8m-faq3qgqSylok$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!_D8UGe5WivvDmk7lBZ_AxTnqwiUR1JDUe1FoePjcRFSY_fCVcLXvESrv_mRJodeLZxW7nqjFN7Bc8m-faq3q0NL2B9A$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!_D8UGe5WivvDmk7lBZ_AxTnqwiUR1JDUe1FoePjcRFSY_fCVcLXvESrv_mRJodeLZxW7nqjFN7Bc8m-faq3q9N3tBJ8$

$$

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From COD Weather Processor @1:2320/107 to All on Sun Jul 19 00:56:36 2026

FOUS30 KWBC 190056
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
856 PM EDT Sat Jul 18 2026

Day 1
Valid 01Z Sun Jul 19 2026 - 12Z Sun Jul 19 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM PORTIONS OF
WEST TEXAS THROUGH THE EASTERN GREAT BASIN, AS WELL AS PARTS OF THE
NORTHEAST AND MID-ATLANTIC...

01Z Update...
The late day ramp up of convective coverage and rainfall intensity
in the western United States will continue through the evening and
into the overnight hours within a monsoonal flow pattern. Some
minor expansions of the Slight Risk area were made to better fit
the afternoon radar trends...but the greatest coverage of intense
rainfall rates were generally confined to the southern tier of
states and this well handled by the previous forecast.

In the eastern United States...one round of convection from earlier
in the day has pretty well run its course and had either weakened
or moved off-shore. However...additional convection being forced a
cold front making its way through the Ohio Valley and Northeast
into parts of New York...Pennsylvania and the Mid-Atlantic region
has the potential to renew flooding or worsen on-going flooding in
areas primed by earlier rainfall. As a result...main changes were
to remove outlook area that were post-frontal but largely left
areas in tact that were pre-frontal.

Bann

Previous Discussion...

...Western Texas to the Four Corners/Great Basin...
Monsoon ridge will become favorably aligned to draw impressive
thermodynamics northward from Mexico, reaching from West Texas
through much of the Desert Southwest and then northward into the
Great Basin and Intermountain West. Multiple weak shortwaves
embedded within the flow will continue to progress anti-
cyclonically around this ridge, bringing locally enhanced ascent
to the region, with a few of these impulses noted on morning WV
imagery in TX and NM. While any of these impulses will locally
enhance ascent leading to clusters of more organized convection
today, the greatest risk is just the breadth of coverage of
thunderstorms with potentially heavy rainfall today.

PWs this morning are impressive across the region, measured via GPS
and morning RAOBs vary from around 1.2 inches at SLC to as high as
2.1 inches at PHX, at or above the 90th percentile across a large
area (and as high as +3 sigma), and that measured PW at PHX this
morning is a daily record. At the same time instability is progged
to climb to 1000-2000 J/kg, locally even higher, as far as 40N
latitude in the Four Corners, which is impressive and is a typical discriminator of more widespread monsoonal heavy rain/flash flood
days.

THe CAMs, including the UA WRF, are aggressive with coverage of
their simulated reflectivity across much of the area today, with
hourly rainfall potentially reaching 1.5 to 2.5 inches. This could
easily exceed the 1-hr FFG across the region, and in some areas the
3-hr FFG even has a high chance (40-60%) of being exceeded where
terrain-tying or boundary-collisions can cause a temporal extension
of the heavy rain rates. With storm motions generally expected to
be weak at 5-10 kts and chaotic, an active day is expected, with
scattered flash flooding expected, especially across vulnerable
features like burn scars, slot canyons, and urban areas.

The inherited SLGT risk was modified to account for recent
guidance, and there was some consideration of an increased risk
based on the impressive REFS exceedance probabilities which rise
above 55% for FFG, but the more muted HREF was used more heavily,
especially since the highest FFG exceedance is across the higher
elevations of the Mogollon Rim and not down into the deserts
(although an expansion SW into some lower terrain was made with
this update).

...Midwest to the Mid Atlantic and Northeast...
A cold front will drop steadily southeast from the Great Lakes,
reaching the lower Ohio Valley and the Mid-Atlantic by Sunday
morning. Ahead of this front, impressive moisture will pool from
Kentucky eastward to Long Island and Cape Cod, where PWs are
already 1.75 to 2.0 inches and will climb above 2.0 inches through
this aftn. The overlap of this elevated PW with increasing SBCAPE
(2000-3000 J/kg forecast) will create robust thermodynamics which
will support widespread convection capable of producing intense
hourly rainfall for which the HREF and REFS suggest has a 40-60%
(10-15% chance) of exceeding 1 inch (2 inches).

The excessive rainfall risk will steadily increase through the aftn
and continue into this evening/tonight as multiple rounds of
thunderstorms develop and track across the area. 0-6km bulk shear is
progged to increase to 30-40 kts ahead of the cold front, and as
weak impulses move west to east from the Ohio Valley into the Mid-
Atlantic, this will allow for some organization into clusters
tracking parallel to the front (and pre-frontal trough). Ahead of
the front, the Corfidi vectors and mean flow will align from the
west, leading to an increased backbuilding potential into the
higher thermodynamics with cells then tracking across the same
areas of the Mid-Atlantic states and into southern New England.
This will occur ahead of the front which will produce a second
round of heavy rainfall potential, albeit with more progressive NW
to SE motion to the cells.

The inherited SLGT risk has been adjusted to account for new
guidance, and due to elevated probabilities from both the HREF and
REFS (40-60% for 3"/24hrs, 10-15% for 5"/24hrs) atop sensitive
areas due to urban development and recent rainfall producing compromised
FFG. This included connecting the SLGT risks across PA where the
ARW guidance is most aggressive and there is sufficient potential
for some training (or meso-cyclones to enhance rainfall rates) to
include a larger area. Considered an elevated internal SLGT risk
for the Tri-State area as well, but enough uncertainty in position
and timing of redevelopment after CAPE exhaustion this morning
prevented that category increase.

...Florida Panhandle through Southwest Georgia...
Deep moisture spreading north ahead of a slow-moving mid-to-upper
level low will pool along a surface trough extending out of the
eastern Gulf. This moisture (PWs increasing to above 2 inches)
will fuel slow-moving storms as Corfidi vectors become aligned
anti-parallel to weak 0-6km mean winds of just 5-10 kts. With rain
rates possibly (20-40%) exceeding 2"/hr at times this could create
at least isolated instances of excessive rainfall leading to flash
flooding.

...Western Florida Peninsula...
A convective MCV positioned west of the Florida Panhandle across
the northeast Gulf will drift westward today within a pool of
tropical PWs nearing 2.25 inches. As this feature drifts slowly
westward, it has, at least this morning, temporarily stalled inflow
along the Florida west coast between Naples and Fort Meyers. The
high-res CAMs are not extremely aggressive with rainfall today,
but have been under-forecasting the current activity (MRMS already
2-4" in some areas with hourly rain rates of 2-3"). If this band
continues to stall, continued impressive rainfall rates are likely,
and the recent RRFS, HRRR, and some of the experimental REFS
members show an additional 2-4" of rain are possible. This has
resulted in a narrow MRGL risk addition which aligns well with
recently issued MPD #764.

Weiss

Day 2
Valid 12Z Sun Jul 19 2026 - 12Z Mon Jul 20 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS THE
SOUTHWESTERN U.S. FROM WEST TEXAS TO SOUTHERN UTAH, AS WELL AS
PORTIONS OF NORTH CAROLINA...

...Southwestern U.S....
The monsoon ridge will persist in a favorable alignment Sunday,
keeping the overall synoptic pattern relatively unchanged from D1.
This will create another day of scattered to widespread convection
from the Desert Southwest, through West Texas, and northward into
the Great Basin and Intermountain West. The primary different
between the synoptic pattern Saturday vs Sunday may be just a
subtle reorganization of the ridge center near the WY/CO border,
which could allow for a subtly farther NW shift of thunderstorm
activity than what occurs Saturday.

Regardless, the environment will support another active day, and
with PWs reaching +2 to +3 sigma (a plume of 0.75" north to 1.75"
south) overlapping widespread MUCAPE of 250-1000 J/kg, this will
support heavy rainfall rates within any of the convection on
Sunday. HREF and REFS neighborhood probabilities indicate a 60-80%
chance of hourly rainfall to 1", with locally 2"/hr rates also
possible (10-20%). Although bulk shear is expected to remain
modest, up to 20 kts, suggesting primarily pulse type convection,
weak 0-6km mean winds and Corfidi vectors will allow for storm
mergers and boundary interactions to cause chaotic and slow
motions, with subtle terrain tying or boundary stalling storms
developing at times. This will create locally 3-4" of rain,
especially from the Mogollon Rim southeast into West Texas where
higher MUCAPE is progged. However, anywhere these slow storms
develop with the intense rain rates, instances of flash flooding
will be possible, especially atop sensitive terrain features like
slot canyons and dry washes, or over burn scars and urban areas.

Once again, the probabilities indicate the heaviest rainfall will
occur in the higher terrain, but light E/NE flow and outflows could
help storms dive off the terrain into the lower deserts at times as
well.

...Mid-Mississippi Valley through the Carolinas...
After coordination with the eastern NC WFOs, a targeted SLGT risk
has been added for eastern NC embedded within the broader MRGL
extending from the Mid-Mississippi Valley through the Tennessee
Valley and into the southern Mid-Atlanic states. This area will see
scattered to widespread thunderstorm development along and ahead of
a cold front which will slowly drop southward through the day. The
downstream environment will be extremely supportive of heavy rain
thanks to PWs of 2-2.25 inches overlapped with MUCAPE above 2000
J/kg.

While much of the convection will be of the pulse variety, some
increasing bulk shear reaching 25-35 kts, especially late across NC
and the Mid-Mississippi Valley could help organize storms into
clusters, which will then move parallel to the boundary to support
prolonged periods of training. With rainfall rates of 2"/hr or
more, this could cause locally more than 3" of rain, with a 20-40%
chance of at least 5" across eastern NC where a shortwave will help
spawn a wave of low pressure to improve ascent and organize
thunderstorm activity.

...Eastern Gulf Coast...
A tropical disturbance (AL91) for which NHC has a 40% of
development over the next 7 days in the northeastern Gulf will
spread at least moderate rainfall onshore the west coast of Florida
through the Panhandle and potentially as far east as eastern
Louisiana. While there is considerable uncertainty into the onshore
extent of QPF on D2, the HREF and REFS both suggest a 20-40% chance
of at least 3" of rainfall along the coast, driving the adjustments
to the inherited MRGL risk.

...Upper Mississippi Valley...
A shortwave embedded within squeezed mid-level flow will crest the
Four-Corners ridge and then dive southeast Sunday evening/night
into the Northern Plains and Upper Midwest. This shortwave will
interact with a frontal system to enhance ascent, with a wave of
low pressure potentially also developing. As the LLJ develops
within the accompanying warm sector, it is progged to accelerate to
25-35 kts, drawing robust thermodynamics (PWs above 2" with MUCAPE
over 3000 J/kg) northward and isentropically ascending the NW to SE
oriented warm front. This will help spawn thunderstorms during the
evening, with backbuilding/training possible from the eastern
Dakotas into southern Minnesota. The HREF and REFS probabilities
suggest a 15-25% chance for at least 3" of rainfall thanks to
training 1-2"/hr rain rates, so a MRGL risk was added for at least
localized flash flood potential.

Weiss

Day 3
Valid 12Z Mon Jul 20 2026 - 12Z Tue Jul 21 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
ARIZONA AND NEW MEXICO...

...Southwest...
Changes from inherited were primarily cosmetic to account for new
guidance, but another day of active (although with somewhat less
coverage than the weekend) monsoonal convection is expected. This
is due to a generally unchanged synoptic pattern with anomalous
moisture supporting convective activity and rainfall efficiency.

South of the ridge, as in the previous few days, shortwaves
rotating westward will help steer and enhance convective coverage,
and where this overlaps with the greatest instability/PW across
NM/AZ should receive the greatest coverage of thunderstorms with
flash flood potential. There is some concern that instability may
struggle to return Monday due to widespread convective coverage and
residual cloud cover Sunday night, which may necessitate
additional adjustments to the risk area, but at this time it still
appears there will be another day of scattered to widespread
convection with at least scattered flash flood instances. This will
be most likely across vulnerable features such as dry washes, burn
scars, and slot canyons.

...Great Lakes...
A well-defined shortwave interacting with deepening moisture is
expected to produce strong storms capable of producing heavy
rainfall across the region. Locally backed and accelerated low-
level flow will help surge PWs to 2 inches or more, especially
within a progressive warm sector progged to race across the region
during D3. This moisture, along with strong ascent driven both by
low-level isentropic ascent and favorable upper jet dynamics, will
fuel the potential for heavy rainfall-producing storms. Increasing
bulk shear to 30-50 kts will help organize convection into clusters
or supercells, raising the potential for intense rain rates of
1-2"/hr, through which any short-term training could enhance the
flood risk. At this time storms may move rapidly enough to preclude
a higher risk, but will continue to monitor for a possible targeted
upgrade to a SLGT risk with later issuances.

...North Carolina/Southern Virginia...
A Marginal Risk was maintained where a front and coinciding pool
of deep moisture (PWs at or above 2 inches) are expected to linger,
extending the threat for heavy rainfall and possible flash
flooding into a second day. There is some potential a SLGT risk may
be needed here as well, but that risk will be somewhat dependent on
what occurs D2, so after coordination with the WFOs, opted to
maintain the MRGL for now and reassess as the event gets closer.

...Florida Gulf Coast...
Considerable uncertainty remains regarding AL91 in the northern
Gulf. There will continue to be at least a low-end risk for heavy
rainfall around this system as tropical moisture streams northward
to the FL Panhandle and surrounding areas. At this time the MRGL
risk was maintained and only cosmetically adjusted, but future
refinements are expected as this system becomes more organized.

Weiss

Day 4 and Day 5

Valid 12Z Tue Jul 21 2026 - 12Z Thu Jul 23 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHWEST AS WELL AS THE CENTRAL APPALACHIANS ON TUESDAY...

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR EASTERN NORTH
CAROLINA AND SOUTHEASTERN VIRGINIA ON WEDNESDAY...

2030Z Discussion...
Few changes needed to either the excessive risk in the eastern US
or the western states. The 12Z model QPF and the ensemble guidance
still aligned fairly closely with previous runs...so changes to the
Day 4/5 ERO were minor adjustments rather than a shift in the
overall forecast reasoning,

Bann

Previous Discussion...

...Southwest...

The Southwest Monsoon will remain in full force across Arizona and
into Utah on Tuesday. Moisture anomalies especially to the north
across Utah could approach 5 sigma above normal for this time of
year, while into Arizona, PWATs to 2 inches will be a solid 3 sigma
above normal. With daytime heating, renewed rounds of thunderstorms
are expected to redevelop for the latest in the multi-afternoon
pattern. Soil moisture levels are already saturated over much of
Arizona and into southern Utah. Expect with the thermal low peaking
in intensity on Tuesday, that flash flooding concerns will become
more widespread as rains impact beyond the 4 Corners into Nevada,
Idaho, and Wyoming. A Slight Risk upgrade was introduced with this
update, and it's possible localized areas may see further upgrades
as Tuesday approaches. By Wednesday, ridging over the Southwest
will push the greater threats for thunderstorms further north into
the Intermountain West, with a low developing over the Plains
allowing for some of the moisture to overspread into portions of
the central Plains. The signal for heavy rain lessens on Wednesday,
so the threat drops to Marginal for now, though a Slight may be
needed into the Intermountain West with continued consistency in
the guidance.

...Central Appalachians...

A Slight Risk upgrade was also introduced for portions of the
Central Appalachians, particularly across West Virginia and into
southwest Pennsylvania. Abundant moisture across the Mid-Atlantic
will interact with a strong cold front pushing southwest across
Ohio during the afternoon. This will allow for numerous
thunderstorms to develop Tuesday afternoon. Upslope flow into the
flash flood prone mountains of West Virginia and Pennsylvania will
support additional thunderstorm development as compared with areas
further west where the front will clear the moisture, and further
east where there will be less forcing. PWATs approaching 2 inches
will also support storms capable of multiple inch per hour rainfall
rates, especially as they run into the mountains.

To the east across the Mid-Atlantic, moisture levels further
increase, with some areas perhaps reaching 2.25 inch PWATs Tuesday
afternoon. The forcing will be a bit more uncertain, but any storms
that form will be capable of very heavy rains. The I-95 corridor
from DC to NYC will have to be closely monitored as these heavily
populated and flood prone areas may have enough widespread activity
to need further upgrades.

...Tidewater of North Carolina and Virginia...

On Day 5/Wednesday, the same cold front that swings through the
Midwest, Northeast, and Mid-Atlantic on Tuesday slows down its
forward speed, perhaps even stalling to the west of the Tidewater
of North Carolina and Virginia. Plentiful tropical moisture
continues riding northeastward along that front, providing ample
opportunity for numerous training showers and thunderstorms to
develop over the region, likely moving out over the Atlantic off
Ocean City, Maryland and points north. Thus, the focus will be in
the highly urbanized Hampton Roads area, extending into much of the
coastal plain of North Carolina. Given the pretty impressive signal
for heavy rain, have started out the Day 5 ERO with a Slight Risk
in this region. There remains some uncertainty as to whether any
tropical development over the northeastern Gulf contributes to the
heavy rainfall expected in this region on Wednesday. Given the
signals for heavy rain expected Sunday/Monday over eastern North
Carolina, expect the soils by Wednesday to be significantly more
saturated than they are now, contributing to the heightened flash
flooding risk.

Wegman

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!9Iz3VMh8qtV8rX_tjwqBWgh4bEitBeKQXGUWlCLkv-qqpwYvtd8alvw_p2t9CiYI4OYs__RQzdPt_KaMWfomBcPoH3k$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!9Iz3VMh8qtV8rX_tjwqBWgh4bEitBeKQXGUWlCLkv-qqpwYvtd8alvw_p2t9CiYI4OYs__RQzdPt_KaMWfomxftDKAI$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!9Iz3VMh8qtV8rX_tjwqBWgh4bEitBeKQXGUWlCLkv-qqpwYvtd8alvw_p2t9CiYI4OYs__RQzdPt_KaMWfomp6WW1DY$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sun Jul 19 08:32:52 2026

FOUS30 KWBC 190832
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
432 AM EDT Sun Jul 19 2026

Day 1
Valid 12Z Sun Jul 19 2026 - 12Z Mon Jul 20 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE SOUTHWESTERN U.S. FROM WEST TEXAS TO SOUTHERN UTAH, AS WELL AS
EASTERN NORTH CAROLINA AND THE VIRGINIA TIDEWATER REGION...

...Southwestern U.S....
Overall, the synoptic pattern remains much the same, with the
monsoon ridge remaining favorably aligned. PW anomalies of 2-3 std
dev above normal will remain across much of the highlighted area.
This moisture, along with sufficient instability, and areas of
enhanced ascent afforded by easterly-drifting mid-level energy.
will support another day of widespread convective activity. Slow-
storm motions along with likely cell-mergers will raise the threat
for locally heavy amounts and flash flooding concerns. Flash
flooding remains a distinct threat in slot canyons, dry washes,
burn scars, and low desert areas via mountain outflows. The Slight
Risk highlights the area where HREF and REFS guidance indicate the
threat for 1-2 inch amounts is greatest. The REFS, and to a lesser
extend the HREF, indicate that heavier totals of 3+ inches are
possible over portions of West Texas along the Mogollon Rim down
into southeastern Arizona.

...Lower Missouri Valley to Southeastern Virginia and Eastern North
Carolina...
A targeted Slight Risk remains centered over eastern North
Carolina and extends into southeastern Virginia. Convection will
develop ahead of a slow-moving cold front that will be dropping
into a very moist (PWs 2+ inches) and unstable (MUCAPE > 2000
J/kg) environment, while some modest right-entrance region upper
jet forcing will offer some enhanced ascent. Heavy totals appear
likely, with both the HREF and REFS showing high neighborhood
probabilities for amounts over 3 inches within the Slight Risk
area.

Less organized activity is expected back along the front extending
across the southern Appalachians, Tennessee Valley, and parts of
the lower Ohio, mid Mississippi, and lower Missouri valleys. While
widespread heavy totals are not expected, the moisture-rich
environment (PWs 1.75-2 inches) is expected to support storms
capable of producing localized heavy amounts and isolated runoff
concerns.

...Eastern Dakotas into the upper Mississippi Valley...
A shortwave moving off of the top of the western U.S. ridge will
interact with a frontal system advancing through the northern
Plains into the Upper Midwest. An amplifying west-southwesterly
low level jet will support increasing PWs (1.75-2 inches) and
instability east of a warm front. The overnight guidance differed
greatly on the details but continued to present some signal for
backbuilding and training storms, capable of producing locally
heavy rates within the area highlighted by the Marginal Risk.

...Eastern Gulf Coast into the Southeast...
An area of low pressure located over the northeastern Gulf is
gradually becoming better defined, with additional development
becoming more likely. The footprint for heavy amounts through early
Monday is expected to remain mostly offshore, although some
heavier amounts along the immediate Florida Gulf Coast cannot be
ruled out. Therefore, the Marginal Risk was maintained.

An axis of enhanced low level convergence and pooling moisture to
the north is still expected be a focus for diurnal storms capable
of producing heavy rates. Therefore, a Marginal Risk was maintained
from the central Gulf Coast northward into the Tennessee Valley.
HREF and REFS indicate localized totals exceeding 2 inches are
likely along this corridor.

Pereira

Day 2
Valid 12Z Mon Jul 20 2026 - 12Z Tue Jul 21 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
WEST TEXAS, NEW MEXICO, AND ARIZONA...

...Southwest and Great Basin...
Mid-level energy moving west of the region, and dry air advection
from the south will begin to diminish the heavy rainfall and flash
flooding threat over West Texas. However farther west, the
monsoonal moisture plume will remain firmly in place, ensuring
another day of high-efficient rainfall production over portions of
the Southwest and Great Basin.

Models show the upper high originally centered over Utah and
Colorado beginning to slide southeast, allowing moisture and
energy to spread northwest into the Great Basin and along the
western slopes of the Sierra Nevada -- raising the potential for
increasing storm activity and isolated runoff concerns in those
area.

The greater heavy rainfall and flash flooding threat will remain
focused from southwestern New Mexico and southeastern Arizona
northwestward along the Mogollon Rim into northwestern Arizona.
This is expected to be the focus for better synoptic forcing and
greater instability -- supporting intense short-duration rain rates
that will elevate the risk for flash flooding, especially in areas
of complex terrain, dry washes, and burn scars.

...Upper Great Lakes...
An amplifying upper trough supported by energy diving out of
Canada will advance from the upper Mississippi Valley to the upper
Great Lakes. Strong southwesterly to west-southwesterly low level
inflow will continue to sustain deep moisture ahead of the cold
front and across the advancing warm front. This moisture along with
strong forcing, produced in part by left-exit region upper jet
dynamics, will generate organized convection capable of producing
rainfall rates of 1-2 in/hr. Fast storm motions should limit the
overall heavy accumulation and flash flooding threat. However,
localized short-term training could raise at least some isolated
concerns.

...North Carolina and Southern Virginia...
Maintained a Marginal Risk across this area. Apart from the GFS and
REFS, the general model consensus indicates that activity will be
less organized. However, a lingering boundary and corresponding
pool of deep moisture (PWs 2+ inches) will support additional
storms capable of producing heavy downpours. Should the guidance
begin to trend more toward the GFS and REFS, a targeted upgrade
may required, especially if more models begin to show back-to-back
days of overlapping heavy amounts.

...Gulf Coast...
The models continue to show the footprint of the heaviest amounts
associated with the disturbance over the northern Gulf remaining
mostly offshore. Therefore maintained only a Marginal Risk along
the coast from West Florida to southeastern Louisiana. Moisture
pooling along an axis of enhanced low level convergence northwest
of the circulation may extend the threat for heavy rainfall further
inland into the far lower Mississippi Valley.

Pereira

Day 3
Valid 12Z Tue Jul 21 2026 - 12Z Wed Jul 22 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHWEST, CENTRAL APPALACHIANS, AND THE MID ATLANTIC COAST...

...Southwest to the northern Rockies...
Models show the upper high continuing to shift east as an upper
trough begins to drift into the Pacific Northwest. This will allow
the monsoon moisture plume to spread further north, with moisture
anomalies over 3 std dev above normal extending as far north as the
northern Rockies. This will support increasing convective
development with isolated flash flooding concerns as far north as
southwestern Montana and southern Idaho.

However, the greater heavy rainfall and flash flooding threat is
expected to remain centered over western New Mexico, Arizona, and
southern Utah. Guidance shows a fairly well-defined shortwave
moving around the western periphery of the upper high, which along
with PWs over 1.5 inches in many spots, and highly sensitive soils,
will likely generate additional widespread storm coverage and flash
flooding concerns. Given the synoptic setup and anomalous
moisture, this can be considered a high-end Slight for parts of the
region and a future upgrade may be required.

...Central Appalachians and Ohio Valley...
A Slight Risk remains in place across portions of the central
Appalachians and Ohio Valley. Moist soils and flood-prone mountain
terrain are likely to contribute to the flash flood threat across
this region. Deep moisture (PWs around 2 inches) will fuel showers
and storms ahead of a strong cold front advancing southeast across
the region. These storms will be capable of producing 1-2 in/hr
rainfall rates, raising flash flooding concerns.

...Mid Atlantic...
A separate Slight Risk has been introduced along the Mid Atlantic
Coast for late Tuesday into early Wednesday. Strengthening
southeasterly flow ahead of the system moving through the Ohio
Valley will transport a deeply anomalous moisture plume into a
region of strong ascent. This combination will support increasing
coverage of showers and storms capable of producing heavy rainfall.
While the exact spatial coverage of heaviest amounts remains
somewhat uncertain, portions of the the more flood-prone urbanized
I-95 corridor appear to likely be impacted, warranting the upgrade
to a Slight Risk.

...Gulf Coast...
With the heavy rainfall footprint associated the Gulf disturbance,
remaining offshore in most of the guidance, continued to maintain
only a Marginal Risk along parts of the immediate Gulf Coast.

Pereira

Day 4 and Day 5
Valid 12Z Wed Jul 22 2026 - 12Z Fri Jul 24 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR THE COASTAL
CAROLINAS AND SOUTHEAST VIRGINIA ON BOTH WEDNESDAY AND THURSDAY...

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE INTERMOUNTAIN WEST ON WEDNESDAY...

...Tidewater Region of Virginia and the Carolinas...

A slow-moving cold front pushing southeast out of the Mid-Atlantic
on Wednesday is likely to continue slowing down its forward speed
as it approaches the Tidewater Region of Virginia and the Carolinas
on Wednesday. Meanwhile, plentiful tropical moisture will be drawn northeastward from the tropical system that will likely be
meandering somewhere near the Louisiana coast on Wednesday. This
moisture will ride northeastward ahead of the front, spiking PWATs
above 2.25 inches over this entire region. The result of a strong
but slow-moving front, well above normal amounts of moisture, and
upper level support in the form of a deep trough over the Northeast
supporting the surface front from behind/north will make for a
nearly ideal scenario for training and backbuilding storms from the
afternoon through the evening.

This Day 4/Wednesday period is likely to be the fourth consecutive
day that showers and thunderstorms have been dropping locally very
heavy rain and multiple-inch rainfall totals somewhere in and
around eastern North Carolina. The front will act to greatly expand
the footprint of heavy rainfall in this area. Since soils are all
but certain to be nearly saturated in this area by Wednesday, flash
flooding concerns continue to increase. Thus, a higher-end Slight
was introduced with this update from Raleigh east, and from
Wilmington north through the Hampton Roads area. It's probable that
should the trends continue to increase both with the expected
rainfall on Wednesday, and the prior days' rainfall in this same
region, that a Moderate Risk upgrade will be needed with future
updates.

By Day 5/Thursday, the front will sag a hair bit further south,
likely sparing the Raleigh and Hampton Roads metros from much
additional rainfall, but instead concentrating the heaviest rains
from the Outer Banks southwest down the coast through Wilmington
and including Charleston, SC in heavy rainfall. The ERO thus was
started this morning with a Slight Risk for this area. Of course,
even just a small increase in forward speed will push the front up
to the coast, which would then concentrate all of the heaviest
rains off the coast, making the Slight Risk an over-forecast.
However, any slower/westward positioning of the front will make
for a 5th consecutive day of heavy rains in eastern North
Carolina...meaning the Slight Risk would be an under-forecast.
Thus, the Slight represents the "happy medium" of these scenarios
and fits best with the current rainfall forecast in the area for
Thursday.

...Intermountain West...

A Slight Risk upgrade was introduced with this update for a portion
of the Intermountain West on Wednesday. The area highlighted
includes all of southeastern Idaho, much of western Wyoming outside
of Yellowstone, as well as far northern Utah and the northwestern
corner of Colorado. Well above normal amounts of atmospheric
moisture to the tune of up to 4 sigma above normal, and PWATs
locally exceeding 1.25 inches will be in place across this region.
An approaching longwave trough will direct a strong shortwave
northeastward during the afternoon hours. This will result in
widespread shower and thunderstorm activity over this area.
Topographic interaction with the storms will locally enhance
rainfall rates, while also supporting impactful flash flooding as
the rain water races down the slopes of the mountains. Due to the
abundant moisture available, the storms will not only be numerous,
but capable of 2 inch/hour rainfall rates with the strongest cores,
a phenomenon not often seen in this part of the country.

Wegman

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!7mnhLYuweXPehEHWJo6U8Ua3utOtKxDL600W42obdz_sNzYpj77nZ2hKlzOmioOla9QYixhmr--U37MgfS6xqu3eOhk$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!7mnhLYuweXPehEHWJo6U8Ua3utOtKxDL600W42obdz_sNzYpj77nZ2hKlzOmioOla9QYixhmr--U37MgfS6xxSJQ_q4$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!7mnhLYuweXPehEHWJo6U8Ua3utOtKxDL600W42obdz_sNzYpj77nZ2hKlzOmioOla9QYixhmr--U37MgfS6xGFy0a8o$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sun Jul 19 09:21:58 2026

FOUS30 KWBC 190921
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
521 AM EDT Sun Jul 19 2026

Day 1
Valid 12Z Sun Jul 19 2026 - 12Z Mon Jul 20 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE SOUTHWESTERN U.S. FROM WEST TEXAS TO SOUTHERN UTAH, AS WELL AS
EASTERN NORTH CAROLINA AND THE VIRGINIA TIDEWATER REGION...

...Southwestern U.S....
Overall, the synoptic pattern remains much the same, with the
monsoon ridge remaining favorably aligned. PW anomalies of 2-3 std
dev above normal will remain across much of the highlighted area.
This moisture, along with sufficient instability, and areas of
enhanced ascent afforded by easterly-drifting mid-level energy.
will support another day of widespread convective activity. Slow-
storm motions along with likely cell-mergers will raise the threat
for locally heavy amounts and flash flooding concerns. Flash
flooding remains a distinct threat in slot canyons, dry washes,
burn scars, and low desert areas via mountain outflows. The Slight
Risk highlights the area where HREF and REFS guidance indicate the
threat for 1-2 inch amounts is greatest. The REFS, and to a lesser
extend the HREF, indicate that heavier totals of 3+ inches are
possible over portions of West Texas along the Mogollon Rim down
into southeastern Arizona.

...Lower Missouri Valley to Southeastern Virginia and Eastern North
Carolina...
A targeted Slight Risk remains centered over eastern North
Carolina and extends into southeastern Virginia. Convection will
develop ahead of a slow-moving cold front that will be dropping
into a very moist (PWs 2+ inches) and unstable (MUCAPE > 2000
J/kg) environment, while some modest right-entrance region upper
jet forcing will offer some enhanced ascent. Heavy totals appear
likely, with both the HREF and REFS showing high neighborhood
probabilities for amounts over 3 inches within the Slight Risk
area.

Less organized activity is expected back along the front extending
across the southern Appalachians, Tennessee Valley, and parts of
the lower Ohio, mid Mississippi, and lower Missouri valleys. While
widespread heavy totals are not expected, the moisture-rich
environment (PWs 1.75-2 inches) is expected to support storms
capable of producing localized heavy amounts and isolated runoff
concerns.

...Eastern Dakotas into the upper Mississippi Valley...
A shortwave moving off of the top of the western U.S. ridge will
interact with a frontal system advancing through the northern
Plains into the Upper Midwest. An amplifying west-southwesterly
low level jet will support increasing PWs (1.75-2 inches) and
instability east of a warm front. The overnight guidance differed
greatly on the details but continued to present some signal for
backbuilding and training storms, capable of producing locally
heavy rates within the area highlighted by the Marginal Risk.

...Eastern Gulf Coast into the Southeast...
An area of low pressure located over the northeastern Gulf is
gradually becoming better defined, with additional development
becoming more likely. The footprint for heavy amounts through early
Monday is expected to remain mostly offshore, although some
heavier amounts along the immediate Florida Gulf Coast cannot be
ruled out. Therefore, the Marginal Risk was maintained.

An axis of enhanced low level convergence and pooling moisture to
the north is still expected be a focus for diurnal storms capable
of producing heavy rates. Therefore, a Marginal Risk was maintained
from the central Gulf Coast northward into the Tennessee Valley.
HREF and REFS indicate localized totals exceeding 2 inches are
likely along this corridor.

Pereira

Day 2
Valid 12Z Mon Jul 20 2026 - 12Z Tue Jul 21 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
WEST TEXAS, NEW MEXICO, AND ARIZONA...

...Southwest and Great Basin...
Mid-level energy moving west of the region, and dry air advection
from the south will begin to diminish the heavy rainfall and flash
flooding threat over West Texas. However farther west, the
monsoonal moisture plume will remain firmly in place, ensuring
another day of high-efficient rainfall production over portions of
the Southwest and Great Basin.

Models show the upper high originally centered over Utah and
Colorado beginning to slide southeast, allowing moisture and
energy to spread northwest into the Great Basin and along the
western slopes of the Sierra Nevada -- raising the potential for
increasing storm activity and isolated runoff concerns in those
area.

The greater heavy rainfall and flash flooding threat will remain
focused from southwestern New Mexico and southeastern Arizona
northwestward along the Mogollon Rim into northwestern Arizona.
This is expected to be the focus for better synoptic forcing and
greater instability -- supporting intense short-duration rain rates
that will elevate the risk for flash flooding, especially in areas
of complex terrain, dry washes, and burn scars.

...Upper Great Lakes...
An amplifying upper trough supported by energy diving out of
Canada will advance from the upper Mississippi Valley to the upper
Great Lakes. Strong southwesterly to west-southwesterly low level
inflow will continue to sustain deep moisture ahead of the cold
front and across the advancing warm front. This moisture along with
strong forcing, produced in part by left-exit region upper jet
dynamics, will generate organized convection capable of producing
rainfall rates of 1-2 in/hr. Fast storm motions should limit the
overall heavy accumulation and flash flooding threat. However,
localized short-term training could raise at least some isolated
concerns.

...North Carolina and Southern Virginia...
Maintained a Marginal Risk across this area. Apart from the GFS and
REFS, the general model consensus indicates that activity will be
less organized. However, a lingering boundary and corresponding
pool of deep moisture (PWs 2+ inches) will support additional
storms capable of producing heavy downpours. Should the guidance
begin to trend more toward the GFS and REFS, a targeted upgrade
may required, especially if more models begin to show back-to-back
days of overlapping heavy amounts.

...Gulf Coast...
The models continue to show the footprint of the heaviest amounts
associated with the disturbance over the northern Gulf remaining
mostly offshore. Therefore maintained only a Marginal Risk along
the coast from West Florida to southeastern Louisiana. Moisture
pooling along an axis of enhanced low level convergence northwest
of the circulation may extend the threat for heavy rainfall further
inland into the far lower Mississippi Valley.

Pereira

Day 3
Valid 12Z Tue Jul 21 2026 - 12Z Wed Jul 22 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHWEST, CENTRAL APPALACHIANS, OHIO VALLEY, AND THE MID ATLANTIC
COAST...

...Southwest to the northern Rockies...
Models show the upper high continuing to shift east as an upper
trough begins to drift into the Pacific Northwest. This will allow
the monsoon moisture plume to spread further north, with moisture
anomalies over 3 std dev above normal extending as far north as the
northern Rockies. This will support increasing convective
development with isolated flash flooding concerns as far north as
southwestern Montana and southern Idaho.

However, the greater heavy rainfall and flash flooding threat is
expected to remain centered over western New Mexico, Arizona, and
southern Utah. Guidance shows a fairly well-defined shortwave
moving around the western periphery of the upper high, which along
with PWs over 1.5 inches in many spots, and highly sensitive soils,
will likely generate additional widespread storm coverage and flash
flooding concerns. Given the synoptic setup and anomalous
moisture, this can be considered a high-end Slight for parts of the
region and a future upgrade may be required.

...Central Appalachians and Ohio Valley...
A Slight Risk remains in place across portions of the central
Appalachians and Ohio Valley. Moist soils and flood-prone mountain
terrain are likely to contribute to the flash flood threat across
this region. Deep moisture (PWs around 2 inches) will fuel showers
and storms ahead of a strong cold front advancing southeast across
the region. These storms will be capable of producing 1-2 in/hr
rainfall rates, raising flash flooding concerns.

...Mid Atlantic...
A separate Slight Risk has been introduced along the Mid Atlantic
Coast for late Tuesday into early Wednesday. Strengthening
southeasterly flow ahead of the system moving through the Ohio
Valley will transport a deeply anomalous moisture plume into a
region of strong ascent. This combination will support increasing
coverage of showers and storms capable of producing heavy rainfall.
While the exact spatial coverage of heaviest amounts remains
somewhat uncertain, portions of the the more flood-prone urbanized
I-95 corridor appear to likely be impacted, warranting the upgrade
to a Slight Risk.

...Gulf Coast...
With the heavy rainfall footprint associated the Gulf disturbance,
remaining offshore in most of the guidance, continued to maintain
only a Marginal Risk along parts of the immediate Gulf Coast.

Pereira

Day 4 and Day 5
Valid 12Z Wed Jul 22 2026 - 12Z Fri Jul 24 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR THE COASTAL
CAROLINAS AND SOUTHEAST VIRGINIA ON BOTH WEDNESDAY AND THURSDAY...

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE INTERMOUNTAIN WEST ON WEDNESDAY...

...Tidewater Region of Virginia and the Carolinas...

A slow-moving cold front pushing southeast out of the Mid-Atlantic
on Wednesday is likely to continue slowing down its forward speed
as it approaches the Tidewater Region of Virginia and the Carolinas
on Wednesday. Meanwhile, plentiful tropical moisture will be drawn northeastward from the tropical system that will likely be
meandering somewhere near the Louisiana coast on Wednesday. This
moisture will ride northeastward ahead of the front, spiking PWATs
above 2.25 inches over this entire region. The result of a strong
but slow-moving front, well above normal amounts of moisture, and
upper level support in the form of a deep trough over the Northeast
supporting the surface front from behind/north will make for a
nearly ideal scenario for training and backbuilding storms from the
afternoon through the evening.

This Day 4/Wednesday period is likely to be the fourth consecutive
day that showers and thunderstorms have been dropping locally very
heavy rain and multiple-inch rainfall totals somewhere in and
around eastern North Carolina. The front will act to greatly expand
the footprint of heavy rainfall in this area. Since soils are all
but certain to be nearly saturated in this area by Wednesday, flash
flooding concerns continue to increase. Thus, a higher-end Slight
was introduced with this update from Raleigh east, and from
Wilmington north through the Hampton Roads area. It's probable that
should the trends continue to increase both with the expected
rainfall on Wednesday, and the prior days' rainfall in this same
region, that a Moderate Risk upgrade will be needed with future
updates.

By Day 5/Thursday, the front will sag a hair bit further south,
likely sparing the Raleigh and Hampton Roads metros from much
additional rainfall, but instead concentrating the heaviest rains
from the Outer Banks southwest down the coast through Wilmington
and including Charleston, SC in heavy rainfall. The ERO thus was
started this morning with a Slight Risk for this area. Of course,
even just a small increase in forward speed will push the front up
to the coast, which would then concentrate all of the heaviest
rains off the coast, making the Slight Risk an over-forecast.
However, any slower/westward positioning of the front will make
for a 5th consecutive day of heavy rains in eastern North
Carolina...meaning the Slight Risk would be an under-forecast.
Thus, the Slight represents the "happy medium" of these scenarios
and fits best with the current rainfall forecast in the area for
Thursday.

...Intermountain West...

A Slight Risk upgrade was introduced with this update for a portion
of the Intermountain West on Wednesday. The area highlighted
includes all of southeastern Idaho, much of western Wyoming outside
of Yellowstone, as well as far northern Utah and the northwestern
corner of Colorado. Well above normal amounts of atmospheric
moisture to the tune of up to 4 sigma above normal, and PWATs
locally exceeding 1.25 inches will be in place across this region.
An approaching longwave trough will direct a strong shortwave
northeastward during the afternoon hours. This will result in
widespread shower and thunderstorm activity over this area.
Topographic interaction with the storms will locally enhance
rainfall rates, while also supporting impactful flash flooding as
the rain water races down the slopes of the mountains. Due to the
abundant moisture available, the storms will not only be numerous,
but capable of 2 inch/hour rainfall rates with the strongest cores,
a phenomenon not often seen in this part of the country.

Wegman

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!6AlZNDNqae1yPTRPz0n-Sgfy95llsNDpD_wdg3imjL-fDHxUBo9ziI46_1OuIzbWagPZ_3qdgwsPu2qQWZyh8R7MZ24$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!6AlZNDNqae1yPTRPz0n-Sgfy95llsNDpD_wdg3imjL-fDHxUBo9ziI46_1OuIzbWagPZ_3qdgwsPu2qQWZyh6WiMhmg$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!6AlZNDNqae1yPTRPz0n-Sgfy95llsNDpD_wdg3imjL-fDHxUBo9ziI46_1OuIzbWagPZ_3qdgwsPu2qQWZyhHSvXoE8$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sun Jul 19 15:57:12 2026

FOUS30 KWBC 191556
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1156 AM EDT Sun Jul 19 2026

Day 1
Valid 16Z Sun Jul 19 2026 - 12Z Mon Jul 20 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE SOUTHWESTERN U.S. FROM WEST TEXAS TO SOUTHWESTERN UTAH, AND EASTERN
NORTH CAROLINA AND THE VIRGINIA TIDEWATER REGION...

...Southwestern U.S...

Overall, the synoptic pattern remains much the same, with the
monsoon ridge remaining favorably aligned. PW anomalies of 2-3
standard deviations above normal will remain across much of the
highlighted area. This moisture, along with sufficient instability,
and areas of enhanced ascent afforded by easterly-drifting mid-
level energy will support another day of scattered to widespread
convective activity. Slow storm motions along with cell mergers
will raise the threat for locally heavy amounts and flash flooding
concerns, particularly for slot canyons, dry washes, burn scars,
and low desert areas via mountain outflows. The Slight Risk
highlights the area where HREF and REFS guidance indicate the
threat for 1-2 inch amounts is greatest. The main change from
overnight is a reduction in the northward extent of the Slight Risk
area over Utah, now confined to far southwestern Utah. Warmer 700mb temperatures north of the Grand Canyon will likely limit the areal
coverage of convection, with a broad Marginal Risk remaining
valid.

...Lower Missouri Valley to Southeastern Virginia and Eastern North
Carolina...

A targeted Slight Risk remains centered over eastern North
Carolina and extends into southeastern Virginia. Convection will
develop ahead of a slow-moving cold front that will be dropping
south into a very moist (PWs 2+ inches) and unstable (MUCAPE >
2000 J/kg) environment, while some modest right-entrance region
upper jet forcing will offer some enhanced ascent. Heavy totals
appear likely, with both the HREF and REFS showing high
neighborhood probabilities for some 2 to 4 inch totals within the
Slight Risk area, mainly between the Hampton Roads area and
Morehead City. There was a minor northward adjustment of the
Marginal and Slight Risk areas across central Virginia to account
for the latest model trends compared to the overnight issuance.

Less organized activity is expected back along the front extending
across the southern Appalachians, Tennessee Valley, and parts of
the lower Ohio, mid Mississippi, and lower Missouri valleys. While
widespread heavy totals are not expected, the moisture-rich
environment (PWs 1.75-2 inches) is expected to support storms
capable of producing localized heavy amounts and isolated runoff
concerns.

...Eastern Dakotas into the upper Mississippi Valley...

A shortwave moving off of the top of the western U.S. ridge will
interact with a frontal system advancing through the northern
Plains into the Upper Midwest. An amplifying west-southwesterly
low level jet will support increasing PWs (1.75-2 inches) and
instability ahead of a frontal boundary. The models have trended the
axis of heaviest rainfall farther north into central and northern
Minnesota, and therefore the existing Marginal Risk area has been
extended to the Minnesota/Canada border. Any new burn scar areas
will be more susceptible to potential flood issues.

...Eastern Gulf Coast into the Southeast...

Newly formed Tropical Depression Two is idling in place across the
northeastern Gulf about 150 miles south of Panama City, Florida.
Recent radar imagery indicates the core of convection and heaviest
rainfall well offshore, and the latest CAM guidance suite
suggests this will remain the case going through the remainder of
the afternoon and into tonight. However, some heavier amounts
along the west coast of Florida are likely with outer feeder bands
and could lead to some localized instances of flooding where
training convection develops. Therefore, the Marginal Risk was
maintained from the overnight issuance.

An axis of enhanced low level convergence and pooling moisture to
the north is still expected be a focus for diurnal storms capable
of producing heavy rainfall rates. Therefore, a Marginal Risk was
maintained from the central Gulf Coast northward into the Tennessee
Valley. Recent CAM guidance indicate localized totals of 1 to 3 inches
across portions of this region through early evening where the most
persistent convection develops.

Pereira/Hamrick

Day 2
Valid 12Z Mon Jul 20 2026 - 12Z Tue Jul 21 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
WEST TEXAS, NEW MEXICO, AND ARIZONA...

...Southwest and Great Basin...
Mid-level energy moving west of the region, and dry air advection
from the south will begin to diminish the heavy rainfall and flash
flooding threat over West Texas. However farther west, the
monsoonal moisture plume will remain firmly in place, ensuring
another day of high-efficient rainfall production over portions of
the Southwest and Great Basin.

Models show the upper high originally centered over Utah and
Colorado beginning to slide southeast, allowing moisture and
energy to spread northwest into the Great Basin and along the
western slopes of the Sierra Nevada -- raising the potential for
increasing storm activity and isolated runoff concerns in those
area.

The greater heavy rainfall and flash flooding threat will remain
focused from southwestern New Mexico and southeastern Arizona
northwestward along the Mogollon Rim into northwestern Arizona.
This is expected to be the focus for better synoptic forcing and
greater instability -- supporting intense short-duration rain rates
that will elevate the risk for flash flooding, especially in areas
of complex terrain, dry washes, and burn scars.

...Upper Great Lakes...
An amplifying upper trough supported by energy diving out of
Canada will advance from the upper Mississippi Valley to the upper
Great Lakes. Strong southwesterly to west-southwesterly low level
inflow will continue to sustain deep moisture ahead of the cold
front and across the advancing warm front. This moisture along with
strong forcing, produced in part by left-exit region upper jet
dynamics, will generate organized convection capable of producing
rainfall rates of 1-2 in/hr. Fast storm motions should limit the
overall heavy accumulation and flash flooding threat. However,
localized short-term training could raise at least some isolated
concerns.

...North Carolina and Southern Virginia...
Maintained a Marginal Risk across this area. Apart from the GFS and
REFS, the general model consensus indicates that activity will be
less organized. However, a lingering boundary and corresponding
pool of deep moisture (PWs 2+ inches) will support additional
storms capable of producing heavy downpours. Should the guidance
begin to trend more toward the GFS and REFS, a targeted upgrade
may required, especially if more models begin to show back-to-back
days of overlapping heavy amounts.

...Gulf Coast...
The models continue to show the footprint of the heaviest amounts
associated with the disturbance over the northern Gulf remaining
mostly offshore. Therefore maintained only a Marginal Risk along
the coast from West Florida to southeastern Louisiana. Moisture
pooling along an axis of enhanced low level convergence northwest
of the circulation may extend the threat for heavy rainfall further
inland into the far lower Mississippi Valley.

Pereira

Day 3
Valid 12Z Tue Jul 21 2026 - 12Z Wed Jul 22 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHWEST, CENTRAL APPALACHIANS, OHIO VALLEY, AND THE MID ATLANTIC
COAST...

...Southwest to the northern Rockies...
Models show the upper high continuing to shift east as an upper
trough begins to drift into the Pacific Northwest. This will allow
the monsoon moisture plume to spread further north, with moisture
anomalies over 3 std dev above normal extending as far north as the
northern Rockies. This will support increasing convective
development with isolated flash flooding concerns as far north as
southwestern Montana and southern Idaho.

However, the greater heavy rainfall and flash flooding threat is
expected to remain centered over western New Mexico, Arizona, and
southern Utah. Guidance shows a fairly well-defined shortwave
moving around the western periphery of the upper high, which along
with PWs over 1.5 inches in many spots, and highly sensitive soils,
will likely generate additional widespread storm coverage and flash
flooding concerns. Given the synoptic setup and anomalous
moisture, this can be considered a high-end Slight for parts of the
region and a future upgrade may be required.

...Central Appalachians and Ohio Valley...
A Slight Risk remains in place across portions of the central
Appalachians and Ohio Valley. Moist soils and flood-prone mountain
terrain are likely to contribute to the flash flood threat across
this region. Deep moisture (PWs around 2 inches) will fuel showers
and storms ahead of a strong cold front advancing southeast across
the region. These storms will be capable of producing 1-2 in/hr
rainfall rates, raising flash flooding concerns.

...Mid Atlantic...
A separate Slight Risk has been introduced along the Mid Atlantic
Coast for late Tuesday into early Wednesday. Strengthening
southeasterly flow ahead of the system moving through the Ohio
Valley will transport a deeply anomalous moisture plume into a
region of strong ascent. This combination will support increasing
coverage of showers and storms capable of producing heavy rainfall.
While the exact spatial coverage of heaviest amounts remains
somewhat uncertain, portions of the the more flood-prone urbanized
I-95 corridor appear to likely be impacted, warranting the upgrade
to a Slight Risk.

...Gulf Coast...
With the heavy rainfall footprint associated the Gulf disturbance,
remaining offshore in most of the guidance, continued to maintain
only a Marginal Risk along parts of the immediate Gulf Coast.

Pereira

Day 4 and Day 5
Valid 12Z Wed Jul 22 2026 - 12Z Fri Jul 24 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR THE COASTAL
CAROLINAS AND SOUTHEAST VIRGINIA ON BOTH WEDNESDAY AND THURSDAY...

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE INTERMOUNTAIN WEST ON WEDNESDAY...

...Tidewater Region of Virginia and the Carolinas...

A slow-moving cold front pushing southeast out of the Mid-Atlantic
on Wednesday is likely to continue slowing down its forward speed
as it approaches the Tidewater Region of Virginia and the Carolinas
on Wednesday. Meanwhile, plentiful tropical moisture will be drawn northeastward from the tropical system that will likely be
meandering somewhere near the Louisiana coast on Wednesday. This
moisture will ride northeastward ahead of the front, spiking PWATs
above 2.25 inches over this entire region. The result of a strong
but slow-moving front, well above normal amounts of moisture, and
upper level support in the form of a deep trough over the Northeast
supporting the surface front from behind/north will make for a
nearly ideal scenario for training and backbuilding storms from the
afternoon through the evening.

This Day 4/Wednesday period is likely to be the fourth consecutive
day that showers and thunderstorms have been dropping locally very
heavy rain and multiple-inch rainfall totals somewhere in and
around eastern North Carolina. The front will act to greatly expand
the footprint of heavy rainfall in this area. Since soils are all
but certain to be nearly saturated in this area by Wednesday, flash
flooding concerns continue to increase. Thus, a higher-end Slight
was introduced with this update from Raleigh east, and from
Wilmington north through the Hampton Roads area. It's probable that
should the trends continue to increase both with the expected
rainfall on Wednesday, and the prior days' rainfall in this same
region, that a Moderate Risk upgrade will be needed with future
updates.

By Day 5/Thursday, the front will sag a hair bit further south,
likely sparing the Raleigh and Hampton Roads metros from much
additional rainfall, but instead concentrating the heaviest rains
from the Outer Banks southwest down the coast through Wilmington
and including Charleston, SC in heavy rainfall. The ERO thus was
started this morning with a Slight Risk for this area. Of course,
even just a small increase in forward speed will push the front up
to the coast, which would then concentrate all of the heaviest
rains off the coast, making the Slight Risk an over-forecast.
However, any slower/westward positioning of the front will make
for a 5th consecutive day of heavy rains in eastern North
Carolina...meaning the Slight Risk would be an under-forecast.
Thus, the Slight represents the "happy medium" of these scenarios
and fits best with the current rainfall forecast in the area for
Thursday.

...Intermountain West...

A Slight Risk upgrade was introduced with this update for a portion
of the Intermountain West on Wednesday. The area highlighted
includes all of southeastern Idaho, much of western Wyoming outside
of Yellowstone, as well as far northern Utah and the northwestern
corner of Colorado. Well above normal amounts of atmospheric
moisture to the tune of up to 4 sigma above normal, and PWATs
locally exceeding 1.25 inches will be in place across this region.
An approaching longwave trough will direct a strong shortwave
northeastward during the afternoon hours. This will result in
widespread shower and thunderstorm activity over this area.
Topographic interaction with the storms will locally enhance
rainfall rates, while also supporting impactful flash flooding as
the rain water races down the slopes of the mountains. Due to the
abundant moisture available, the storms will not only be numerous,
but capable of 2 inch/hour rainfall rates with the strongest cores,
a phenomenon not often seen in this part of the country.

Wegman

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!9WSxrz-3a56wOFyFp1oS3vuIlWyfkmqDCaelJjgXtt0q1pEQqNY3rNXif1oIVGcP66rkvi8uCJvFlEby_L3XweknL80$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!9WSxrz-3a56wOFyFp1oS3vuIlWyfkmqDCaelJjgXtt0q1pEQqNY3rNXif1oIVGcP66rkvi8uCJvFlEby_L3Xvgx8hzk$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!9WSxrz-3a56wOFyFp1oS3vuIlWyfkmqDCaelJjgXtt0q1pEQqNY3rNXif1oIVGcP66rkvi8uCJvFlEby_L3XncxYQMo$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sun Jul 19 19:27:50 2026

FOUS30 KWBC 191927
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
327 PM EDT Sun Jul 19 2026

Day 1
Valid 16Z Sun Jul 19 2026 - 12Z Mon Jul 20 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE SOUTHWESTERN U.S. FROM WEST TEXAS TO SOUTHWESTERN UTAH, AND EASTERN
NORTH CAROLINA AND THE VIRGINIA TIDEWATER REGION...

...Southwestern U.S...

Overall, the synoptic pattern remains much the same, with the
monsoon ridge remaining favorably aligned. PW anomalies of 2-3
standard deviations above normal will remain across much of the
highlighted area. This moisture, along with sufficient instability,
and areas of enhanced ascent afforded by easterly-drifting mid-
level energy will support another day of scattered to widespread
convective activity. Slow storm motions along with cell mergers
will raise the threat for locally heavy amounts and flash flooding
concerns, particularly for slot canyons, dry washes, burn scars,
and low desert areas via mountain outflows. The Slight Risk
highlights the area where HREF and REFS guidance indicate the
threat for 1-2 inch amounts is greatest. The main change from
overnight is a reduction in the northward extent of the Slight Risk
area over Utah, now confined to far southwestern Utah. Warmer 700mb temperatures north of the Grand Canyon will likely limit the areal
coverage of convection, with a broad Marginal Risk remaining
valid.

...Lower Missouri Valley to Southeastern Virginia and Eastern North
Carolina...

A targeted Slight Risk remains centered over eastern North
Carolina and extends into southeastern Virginia. Convection will
develop ahead of a slow-moving cold front that will be dropping
south into a very moist (PWs 2+ inches) and unstable (MUCAPE >
2000 J/kg) environment, while some modest right-entrance region
upper jet forcing will offer some enhanced ascent. Heavy totals
appear likely, with both the HREF and REFS showing high
neighborhood probabilities for some 2 to 4 inch totals within the
Slight Risk area, mainly between the Hampton Roads area and
Morehead City. There was a minor northward adjustment of the
Marginal and Slight Risk areas across central Virginia to account
for the latest model trends compared to the overnight issuance.

Less organized activity is expected back along the front extending
across the southern Appalachians, Tennessee Valley, and parts of
the lower Ohio, mid Mississippi, and lower Missouri valleys. While
widespread heavy totals are not expected, the moisture-rich
environment (PWs 1.75-2 inches) is expected to support storms
capable of producing localized heavy amounts and isolated runoff
concerns.

...Eastern Dakotas into the upper Mississippi Valley...

A shortwave moving off of the top of the western U.S. ridge will
interact with a frontal system advancing through the northern
Plains into the Upper Midwest. An amplifying west-southwesterly
low level jet will support increasing PWs (1.75-2 inches) and
instability ahead of a frontal boundary. The models have trended the
axis of heaviest rainfall farther north into central and northern
Minnesota, and therefore the existing Marginal Risk area has been
extended to the Minnesota/Canada border. Any new burn scar areas
will be more susceptible to potential flood issues.

...Eastern Gulf Coast into the Southeast...

Newly formed Tropical Depression Two is idling in place across the
northeastern Gulf about 150 miles south of Panama City, Florida.
Recent radar imagery indicates the core of convection and heaviest
rainfall well offshore, and the latest CAM guidance suite
suggests this will remain the case going through the remainder of
the afternoon and into tonight. However, some heavier amounts
along the west coast of Florida are likely with outer feeder bands
and could lead to some localized instances of flooding where
training convection develops. Therefore, the Marginal Risk was
maintained from the overnight issuance.

An axis of enhanced low level convergence and pooling moisture to
the north is still expected be a focus for diurnal storms capable
of producing heavy rainfall rates. Therefore, a Marginal Risk was
maintained from the central Gulf Coast northward into the Tennessee
Valley. Recent CAM guidance indicate localized totals of 1 to 3 inches
across portions of this region through early evening where the most
persistent convection develops.

Pereira/Hamrick

Day 2
Valid 12Z Mon Jul 20 2026 - 12Z Tue Jul 21 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
THE DESERT SOUTHWEST AND NORTH CAROLINA...

...Southwest and Great Basin...

Mid-level energy moving west of the region, and dry air advection
from the south will begin to diminish the heavy rainfall and flash
flooding threat over West Texas. However farther west, the
monsoonal moisture plume will remain firmly in place, ensuring
another day of efficient rainfall production over portions of the
Southwest and Great Basin. Models show the upper high originally
centered over Utah and Colorado beginning to slide southeast,
allowing moisture and energy to spread northwest into the Great
Basin and along the western slopes of the Sierra Nevada, raising
the potential for increasing storm activity and isolated runoff
concerns in those areas.

The greater heavy rainfall and flash flooding threat will remain
focused from southwestern New Mexico and southeastern Arizona
northwestward along the Mogollon Rim into northwestern Arizona.
This is expected to be the focus for better synoptic forcing and
greater instability, supporting intense short-duration rain rates
that will elevate the risk for flash flooding, especially in areas
of complex terrain, dry washes, and burn scars. For the 19Z Update,
a minor westward extension of the Slight Risk was made across
northwestern Arizona to the Lake Mead area.

...Upper Great Lakes...

An amplifying upper trough supported by energy diving out of
Canada will advance from the upper Mississippi Valley to the upper
Great Lakes. Strong southwesterly to west-southwesterly low level
inflow will continue to sustain deep moisture ahead of the cold
front and across the advancing warm front. This moisture along with
strong forcing, produced in part by left-exit region upper jet
dynamics, will generate organized convection capable of producing
rainfall rates of 1-2 in/hr. Fast storm motions should limit the
overall heavy accumulation and flash flooding threat. However,
localized short-term training could raise at least some isolated
concerns. No changes were needed here for the updated Day 2
outlook.

...North Carolina and Southern Virginia...

A lingering boundary and corresponding pool of deep moisture
convergence, with PWs generally near or slightly above 2 inches,
will support additional thunderstorms capable of producing heavy
downpours. There has been a trend for heavier QPF in today's
guidance across much of central and eastern North Carolina, and
after consultation with the local WFOs, a Slight Risk area has been
introduced for this area. Heavy rainfall expected through Sunday
night will lead to reduced FFGs and more saturated soils that will
be more prone to flooding issues.

...Gulf Coast...

The models continue to show the footprint of the heaviest amounts
associated with Tropical Depression Two over the northern Gulf
remaining mostly offshore. The Marginal Risk has been maintained along
the coast from West Florida near Tampa, to southeastern Louisiana,
which encompasses areas generally along the Interstate 10 corridor,
with the highest totals likely near the Big Bend of Florida. Moisture
pooling along an axis of enhanced low level convergence northwest
of the circulation may extend the threat for heavy rainfall further
inland into the far lower Mississippi Valley. If there are
northward trends in later model cycles, it is possible that a
Slight Risk could eventually be needed for portions of this outlook
area.

Pereira/Hamrick

Day 3
Valid 12Z Tue Jul 21 2026 - 12Z Wed Jul 22 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHWEST, CENTRAL APPALACHIANS, OHIO VALLEY, AND THE MID ATLANTIC
COAST...

...Southwest to the northern Rockies...
Models show the upper high continuing to shift east as an upper
trough begins to drift into the Pacific Northwest. This will allow
the monsoon moisture plume to spread further north, with moisture
anomalies over 3 std dev above normal extending as far north as the
northern Rockies. This will support increasing convective
development with isolated flash flooding concerns as far north as
southwestern Montana and southern Idaho.

However, the greater heavy rainfall and flash flooding threat is
expected to remain centered over western New Mexico, Arizona, and
southern Utah. Guidance shows a fairly well-defined shortwave
moving around the western periphery of the upper high, which along
with PWs over 1.5 inches in many spots, and highly sensitive soils,
will likely generate additional widespread storm coverage and flash
flooding concerns. Given the synoptic setup and anomalous
moisture, this can be considered a high-end Slight for parts of the
region and a future upgrade may be required.

...Central Appalachians and Ohio Valley...
A Slight Risk remains in place across portions of the central
Appalachians and Ohio Valley. Moist soils and flood-prone mountain
terrain are likely to contribute to the flash flood threat across
this region. Deep moisture (PWs around 2 inches) will fuel showers
and storms ahead of a strong cold front advancing southeast across
the region. These storms will be capable of producing 1-2 in/hr
rainfall rates, raising flash flooding concerns.

...Mid Atlantic...
A separate Slight Risk has been introduced along the Mid Atlantic
Coast for late Tuesday into early Wednesday. Strengthening
southeasterly flow ahead of the system moving through the Ohio
Valley will transport a deeply anomalous moisture plume into a
region of strong ascent. This combination will support increasing
coverage of showers and storms capable of producing heavy rainfall.
While the exact spatial coverage of heaviest amounts remains
somewhat uncertain, portions of the the more flood-prone urbanized
I-95 corridor appear to likely be impacted, warranting the upgrade
to a Slight Risk.

...Gulf Coast...
With the heavy rainfall footprint associated the Gulf disturbance,
remaining offshore in most of the guidance, continued to maintain
only a Marginal Risk along parts of the immediate Gulf Coast.

Pereira

Day 4 and Day 5

Valid 12Z Wed Jul 22 2026 - 12Z Fri Jul 24 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ALONG PORTIONS OF
THE SOUTHEAST US AND CENTRAL/WESTERN GULF COAST...

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE INTERMOUNTAIN WEST AND CENTRAl PLAINS ON WEDNESDAY...

2030Z Discussion...
Introduced a Slight Risk area along the central Gulf coast on
Tuesday and central to western Gulf coast on Wednesday along the
path of Tropical Depression 2. Given the amount of shear across the system...the maximum rainfall amounts be displaced to the south of
the system which would place it in very narrow corridor along the
coast or placed off-shore. But the on-shore fetch of moisture
around the center is enough to warrant a Slight for the time being.
Until the degree of ridging to the north is resolved...and how
much dry air that feeds into the system or its influences on the
track...there is too much uncertainty to highlight any more than a
Slight Risk area at this point.

Otherwise...introduced a SLight Risk area over portions of the
Central US as shortwave energy ejecting from the Rockies interacts
with a low level boundary to produce convection in an anomalously
moist airmass capable of supporting locally heavy rainfall.

No other changes needed elsewhere.

Bann

Previous Discussion...

...Tidewater Region of Virginia and the Carolinas...

A slow-moving cold front pushing southeast out of the Mid-Atlantic
on Wednesday is likely to continue slowing down its forward speed
as it approaches the Tidewater Region of Virginia and the Carolinas
on Wednesday. Meanwhile, plentiful tropical moisture will be drawn northeastward from the tropical system that will likely be
meandering somewhere near the Louisiana coast on Wednesday. This
moisture will ride northeastward ahead of the front, spiking PWATs
above 2.25 inches over this entire region. The result of a strong
but slow-moving front, well above normal amounts of moisture, and
upper level support in the form of a deep trough over the Northeast
supporting the surface front from behind/north will make for a
nearly ideal scenario for training and backbuilding storms from the
afternoon through the evening.

This Day 4/Wednesday period is likely to be the fourth consecutive
day that showers and thunderstorms have been dropping locally very
heavy rain and multiple-inch rainfall totals somewhere in and
around eastern North Carolina. The front will act to greatly expand
the footprint of heavy rainfall in this area. Since soils are all
but certain to be nearly saturated in this area by Wednesday, flash
flooding concerns continue to increase. Thus, a higher-end Slight
was introduced with this update from Raleigh east, and from
Wilmington north through the Hampton Roads area. It's probable that
should the trends continue to increase both with the expected
rainfall on Wednesday, and the prior days' rainfall in this same
region, that a Moderate Risk upgrade will be needed with future
updates.

By Day 5/Thursday, the front will sag a hair bit further south,
likely sparing the Raleigh and Hampton Roads metros from much
additional rainfall, but instead concentrating the heaviest rains
from the Outer Banks southwest down the coast through Wilmington
and including Charleston, SC in heavy rainfall. The ERO thus was
started this morning with a Slight Risk for this area. Of course,
even just a small increase in forward speed will push the front up
to the coast, which would then concentrate all of the heaviest
rains off the coast, making the Slight Risk an over-forecast.
However, any slower/westward positioning of the front will make
for a 5th consecutive day of heavy rains in eastern North
Carolina...meaning the Slight Risk would be an under-forecast.
Thus, the Slight represents the "happy medium" of these scenarios
and fits best with the current rainfall forecast in the area for
Thursday.

...Intermountain West...

A Slight Risk upgrade was introduced with this update for a portion
of the Intermountain West on Wednesday. The area highlighted
includes all of southeastern Idaho, much of western Wyoming outside
of Yellowstone, as well as far northern Utah and the northwestern
corner of Colorado. Well above normal amounts of atmospheric
moisture to the tune of up to 4 sigma above normal, and PWATs
locally exceeding 1.25 inches will be in place across this region.
An approaching longwave trough will direct a strong shortwave
northeastward during the afternoon hours. This will result in
widespread shower and thunderstorm activity over this area.
Topographic interaction with the storms will locally enhance
rainfall rates, while also supporting impactful flash flooding as
the rain water races down the slopes of the mountains. Due to the
abundant moisture available, the storms will not only be numerous,
but capable of 2 inch/hour rainfall rates with the strongest cores,
a phenomenon not often seen in this part of the country.

Wegman

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!-F_SN0MTPDnGms0RAZX0xhGBO2JUCtIwzCzYXT7JYqMLDChRWV1gpGJcD4PpEg6KmO5Yd7C5YJKzYNt8R6paq7wPB20$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!-F_SN0MTPDnGms0RAZX0xhGBO2JUCtIwzCzYXT7JYqMLDChRWV1gpGJcD4PpEg6KmO5Yd7C5YJKzYNt8R6paoKPYvX4$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!-F_SN0MTPDnGms0RAZX0xhGBO2JUCtIwzCzYXT7JYqMLDChRWV1gpGJcD4PpEg6KmO5Yd7C5YJKzYNt8R6payfXNMGE$

$$

= = =
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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sun Jul 19 20:17:14 2026

FOUS30 KWBC 192016
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
416 PM EDT Sun Jul 19 2026

Day 1
Valid 16Z Sun Jul 19 2026 - 12Z Mon Jul 20 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE SOUTHWESTERN U.S. FROM WEST TEXAS TO SOUTHWESTERN UTAH, AND EASTERN
NORTH CAROLINA AND THE VIRGINIA TIDEWATER REGION...

...Southwestern U.S...

Overall, the synoptic pattern remains much the same, with the
monsoon ridge remaining favorably aligned. PW anomalies of 2-3
standard deviations above normal will remain across much of the
highlighted area. This moisture, along with sufficient instability,
and areas of enhanced ascent afforded by easterly-drifting mid-
level energy will support another day of scattered to widespread
convective activity. Slow storm motions along with cell mergers
will raise the threat for locally heavy amounts and flash flooding
concerns, particularly for slot canyons, dry washes, burn scars,
and low desert areas via mountain outflows. The Slight Risk
highlights the area where HREF and REFS guidance indicate the
threat for 1-2 inch amounts is greatest. The main change from
overnight is a reduction in the northward extent of the Slight Risk
area over Utah, now confined to far southwestern Utah. Warmer 700mb temperatures north of the Grand Canyon will likely limit the areal
coverage of convection, with a broad Marginal Risk remaining
valid.

...Lower Missouri Valley to Southeastern Virginia and Eastern North
Carolina...

A targeted Slight Risk remains centered over eastern North
Carolina and extends into southeastern Virginia. Convection will
develop ahead of a slow-moving cold front that will be dropping
south into a very moist (PWs 2+ inches) and unstable (MUCAPE >
2000 J/kg) environment, while some modest right-entrance region
upper jet forcing will offer some enhanced ascent. Heavy totals
appear likely, with both the HREF and REFS showing high
neighborhood probabilities for some 2 to 4 inch totals within the
Slight Risk area, mainly between the Hampton Roads area and
Morehead City. There was a minor northward adjustment of the
Marginal and Slight Risk areas across central Virginia to account
for the latest model trends compared to the overnight issuance.

Less organized activity is expected back along the front extending
across the southern Appalachians, Tennessee Valley, and parts of
the lower Ohio, mid Mississippi, and lower Missouri valleys. While
widespread heavy totals are not expected, the moisture-rich
environment (PWs 1.75-2 inches) is expected to support storms
capable of producing localized heavy amounts and isolated runoff
concerns.

...Eastern Dakotas into the upper Mississippi Valley...

A shortwave moving off of the top of the western U.S. ridge will
interact with a frontal system advancing through the northern
Plains into the Upper Midwest. An amplifying west-southwesterly
low level jet will support increasing PWs (1.75-2 inches) and
instability ahead of a frontal boundary. The models have trended the
axis of heaviest rainfall farther north into central and northern
Minnesota, and therefore the existing Marginal Risk area has been
extended to the Minnesota/Canada border. Any new burn scar areas
will be more susceptible to potential flood issues.

...Eastern Gulf Coast into the Southeast...

Newly formed Tropical Depression Two is idling in place across the
northeastern Gulf about 150 miles south of Panama City, Florida.
Recent radar imagery indicates the core of convection and heaviest
rainfall well offshore, and the latest CAM guidance suite
suggests this will remain the case going through the remainder of
the afternoon and into tonight. However, some heavier amounts
along the west coast of Florida are likely with outer feeder bands
and could lead to some localized instances of flooding where
training convection develops. Therefore, the Marginal Risk was
maintained from the overnight issuance.

An axis of enhanced low level convergence and pooling moisture to
the north is still expected be a focus for diurnal storms capable
of producing heavy rainfall rates. Therefore, a Marginal Risk was
maintained from the central Gulf Coast northward into the Tennessee
Valley. Recent CAM guidance indicate localized totals of 1 to 3 inches
across portions of this region through early evening where the most
persistent convection develops.

Pereira/Hamrick

Day 2
Valid 12Z Mon Jul 20 2026 - 12Z Tue Jul 21 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
THE DESERT SOUTHWEST AND NORTH CAROLINA...

...Southwest and Great Basin...

Mid-level energy moving west of the region, and dry air advection
from the south will begin to diminish the heavy rainfall and flash
flooding threat over West Texas. However farther west, the
monsoonal moisture plume will remain firmly in place, ensuring
another day of efficient rainfall production over portions of the
Southwest and Great Basin. Models show the upper high originally
centered over Utah and Colorado beginning to slide southeast,
allowing moisture and energy to spread northwest into the Great
Basin and along the western slopes of the Sierra Nevada, raising
the potential for increasing storm activity and isolated runoff
concerns in those areas.

The greater heavy rainfall and flash flooding threat will remain
focused from southwestern New Mexico and southeastern Arizona
northwestward along the Mogollon Rim into northwestern Arizona.
This is expected to be the focus for better synoptic forcing and
greater instability, supporting intense short-duration rain rates
that will elevate the risk for flash flooding, especially in areas
of complex terrain, dry washes, and burn scars. For the 19Z Update,
a minor westward extension of the Slight Risk was made across
northwestern Arizona to the Lake Mead area.

...Upper Great Lakes...

An amplifying upper trough supported by energy diving out of
Canada will advance from the upper Mississippi Valley to the upper
Great Lakes. Strong southwesterly to west-southwesterly low level
inflow will continue to sustain deep moisture ahead of the cold
front and across the advancing warm front. This moisture along with
strong forcing, produced in part by left-exit region upper jet
dynamics, will generate organized convection capable of producing
rainfall rates of 1-2 in/hr. Fast storm motions should limit the
overall heavy accumulation and flash flooding threat. However,
localized short-term training could raise at least some isolated
concerns. No changes were needed here for the updated Day 2
outlook.

...North Carolina and Southern Virginia...

A lingering boundary and corresponding pool of deep moisture
convergence, with PWs generally near or slightly above 2 inches,
will support additional thunderstorms capable of producing heavy
downpours. There has been a trend for heavier QPF in today's
guidance across much of central and eastern North Carolina, and
after consultation with the local WFOs, a Slight Risk area has been
introduced for this area. Heavy rainfall expected through Sunday
night will lead to reduced FFGs and more saturated soils that will
be more prone to flooding issues.

...Gulf Coast...

The models continue to show the footprint of the heaviest amounts
associated with Tropical Depression Two over the northern Gulf
remaining mostly offshore. The Marginal Risk has been maintained along
the coast from West Florida near Tampa, to southeastern Louisiana,
which encompasses areas generally along the Interstate 10 corridor,
with the highest totals likely near the Big Bend of Florida. Moisture
pooling along an axis of enhanced low level convergence northwest
of the circulation may extend the threat for heavy rainfall further
inland into the far lower Mississippi Valley. If there are
northward trends in later model cycles, it is possible that a
Slight Risk could eventually be needed for portions of this outlook
area.

Pereira/Hamrick

Day 3
Valid 12Z Tue Jul 21 2026 - 12Z Wed Jul 22 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHWEST AND EASTERN KENTUCKY TO THE DELMARVA...

...Southwest to the northern Rockies...

Models show the upper high continuing to shift east as an upper
trough begins to drift into the Pacific Northwest. This will allow
the monsoon moisture plume to spread farther north, with moisture
anomalies over 3 standard deviations above normal extending as far
north as the northern Rockies. This will support increasing
convective development with isolated flash flooding concerns as far
north as southwestern Montana and southern Idaho.

However, the greater heavy rainfall and flash flooding threat is
expected to remain centered over western New Mexico, central and
northern Arizona, and southern Utah. Guidance shows a fairly well-
defined shortwave moving around the western periphery of the upper
high, which along with PWs over 1.5 inches in many spots, and
highly sensitive soils, will likely generate additional widespread
storm coverage and flash flooding concerns. Given the synoptic
setup and anomalous moisture, this can be considered a high-end
Slight for parts of Arizona and a potential upgrade to Moderate
Risk may be required in future outlooks if models trend higher.
No major changes were needed for this region in the 20Z update.

...Ohio Valley to the Mid-Atlantic...

Upon examination of the 12Z model and CAM guidance suite, there is
a general upward trend in expected QPF across more of the region to
include the central Appalachians and Blue Ridge Mountains, and
therefore the two existing Slight Risk areas were merged into a
single larger area extending from eastern Kentucky to the DelMarVa.
Moist soils and flood-prone mountain terrain are likely to
contribute to the flash flood threat across this region. Deep
moisture (PWs around 2 inches) will fuel showers and storms ahead
of a strong cold front advancing southeast across the region. These
storms will be capable of producing 1-2 in/hr rainfall rates,
raising flash flooding concerns. The Marginal Risk area was also
extended northeastward to include more of central New England where
some of the deterministic guidance supports the idea for some 1-2
inch rainfall maxima.

Farther east across the Mid-Atlantic, strengthening southeasterly
flow ahead of the system moving through the Ohio Valley will
transport an anomalous moisture plume into a region of strong
ascent. This combination will support increasing coverage of
showers and storms capable of producing heavy rainfall. While the
exact spatial coverage of heaviest amounts remains somewhat
uncertain, portions of the the more flood-prone urbanized I-95
corridor could be impacted, warranting the continuance of the Slight
Risk area.

...Gulf Coast...

With the heavy rainfall footprint associated with Tropical
Depression Two remaining offshore in most of the guidance, we
continued to maintain only a Marginal Risk for the central/eastern
Gulf Coast that is mainly confined to the Interstate 10 corridor
and to the coast. Any northward trends will need to be monitored in
case the heavier core of rainfall reaches the coast, which could
necessitate the need for a future Slight Risk.

Pereira/Hamrick

Day 4 and Day 5

Valid 12Z Wed Jul 22 2026 - 12Z Fri Jul 24 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ALONG PORTIONS OF
THE SOUTHEAST US AND CENTRAL/WESTERN GULF COAST...

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE INTERMOUNTAIN WEST AND CENTRAl PLAINS ON WEDNESDAY...

2030Z Discussion...
Introduced a Slight Risk area along the central Gulf coast on
Tuesday and central to western Gulf coast on Wednesday along the
path of Tropical Depression 2. Given the amount of shear across the system...the maximum rainfall amounts be displaced to the south of
the system which would place it in very narrow corridor along the
coast or placed off-shore. But the on-shore fetch of moisture
around the center is enough to warrant a Slight for the time being.
Until the degree of ridging to the north is resolved...and how
much dry air that feeds into the system or its influences on the
track...there is too much uncertainty to highlight any more than a
Slight Risk area at this point.

Otherwise...introduced a SLight Risk area over portions of the
Central US as shortwave energy ejecting from the Rockies interacts
with a low level boundary to produce convection in an anomalously
moist airmass capable of supporting locally heavy rainfall.

No other changes needed elsewhere.

Bann

Previous Discussion...

...Tidewater Region of Virginia and the Carolinas...

A slow-moving cold front pushing southeast out of the Mid-Atlantic
on Wednesday is likely to continue slowing down its forward speed
as it approaches the Tidewater Region of Virginia and the Carolinas
on Wednesday. Meanwhile, plentiful tropical moisture will be drawn northeastward from the tropical system that will likely be
meandering somewhere near the Louisiana coast on Wednesday. This
moisture will ride northeastward ahead of the front, spiking PWATs
above 2.25 inches over this entire region. The result of a strong
but slow-moving front, well above normal amounts of moisture, and
upper level support in the form of a deep trough over the Northeast
supporting the surface front from behind/north will make for a
nearly ideal scenario for training and backbuilding storms from the
afternoon through the evening.

This Day 4/Wednesday period is likely to be the fourth consecutive
day that showers and thunderstorms have been dropping locally very
heavy rain and multiple-inch rainfall totals somewhere in and
around eastern North Carolina. The front will act to greatly expand
the footprint of heavy rainfall in this area. Since soils are all
but certain to be nearly saturated in this area by Wednesday, flash
flooding concerns continue to increase. Thus, a higher-end Slight
was introduced with this update from Raleigh east, and from
Wilmington north through the Hampton Roads area. It's probable that
should the trends continue to increase both with the expected
rainfall on Wednesday, and the prior days' rainfall in this same
region, that a Moderate Risk upgrade will be needed with future
updates.

By Day 5/Thursday, the front will sag a hair bit further south,
likely sparing the Raleigh and Hampton Roads metros from much
additional rainfall, but instead concentrating the heaviest rains
from the Outer Banks southwest down the coast through Wilmington
and including Charleston, SC in heavy rainfall. The ERO thus was
started this morning with a Slight Risk for this area. Of course,
even just a small increase in forward speed will push the front up
to the coast, which would then concentrate all of the heaviest
rains off the coast, making the Slight Risk an over-forecast.
However, any slower/westward positioning of the front will make
for a 5th consecutive day of heavy rains in eastern North
Carolina...meaning the Slight Risk would be an under-forecast.
Thus, the Slight represents the "happy medium" of these scenarios
and fits best with the current rainfall forecast in the area for
Thursday.

...Intermountain West...

A Slight Risk upgrade was introduced with this update for a portion
of the Intermountain West on Wednesday. The area highlighted
includes all of southeastern Idaho, much of western Wyoming outside
of Yellowstone, as well as far northern Utah and the northwestern
corner of Colorado. Well above normal amounts of atmospheric
moisture to the tune of up to 4 sigma above normal, and PWATs
locally exceeding 1.25 inches will be in place across this region.
An approaching longwave trough will direct a strong shortwave
northeastward during the afternoon hours. This will result in
widespread shower and thunderstorm activity over this area.
Topographic interaction with the storms will locally enhance
rainfall rates, while also supporting impactful flash flooding as
the rain water races down the slopes of the mountains. Due to the
abundant moisture available, the storms will not only be numerous,
but capable of 2 inch/hour rainfall rates with the strongest cores,
a phenomenon not often seen in this part of the country.

Wegman

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!-JKDoSoz2PUnaErojfRLgjCqVk47eLhUo4_QjjZJpCaKUZih_omnUUmyO-EC4PfQ8uh7P8irvFan32CQ40f3aU4sIOc$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!-JKDoSoz2PUnaErojfRLgjCqVk47eLhUo4_QjjZJpCaKUZih_omnUUmyO-EC4PfQ8uh7P8irvFan32CQ40f32ZZttOY$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!-JKDoSoz2PUnaErojfRLgjCqVk47eLhUo4_QjjZJpCaKUZih_omnUUmyO-EC4PfQ8uh7P8irvFan32CQ40f3g4lg1tg$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Jul 20 00:49:18 2026

FOUS30 KWBC 200049
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
849 PM EDT Sun Jul 19 2026

Day 1
Valid 01Z Mon Jul 20 2026 - 12Z Mon Jul 20 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE SOUTHWESTERN U.S. FROM WEST TEXAS TO SOUTHWESTERN UTAH, AND EASTERN
NORTH CAROLINA...

01Z Update...
Only minor changes needed to the previously highlighted areas given
the synoptic pattern largely remaining the same. Some territory was
removed from the Marginal Risk area in the Ohio/Tennessee Valley to
the Virginia Tidewater in response to the southward progression of
a front in the area. However...locally heavy rainfall is a concern
farther south in closer proximity to Tropical Depression Two. At
the same time...expanded the Marginal a bit westward in the Dakotas
based on short term radar trends with additional convection still
possible once the low level jet develops. No change needed in the
West.

Bann

Previous Discussion...

...Southwestern U.S...

Overall, the synoptic pattern remains much the same, with the
monsoon ridge remaining favorably aligned. PW anomalies of 2-3
standard deviations above normal will remain across much of the
highlighted area. This moisture, along with sufficient instability,
and areas of enhanced ascent afforded by easterly-drifting mid-
level energy will support another day of scattered to widespread
convective activity. Slow storm motions along with cell mergers
will raise the threat for locally heavy amounts and flash flooding
concerns, particularly for slot canyons, dry washes, burn scars,
and low desert areas via mountain outflows. The Slight Risk
highlights the area where HREF and REFS guidance indicate the
threat for 1-2 inch amounts is greatest. The main change from
overnight is a reduction in the northward extent of the Slight Risk
area over Utah, now confined to far southwestern Utah. Warmer 700mb temperatures north of the Grand Canyon will likely limit the areal
coverage of convection, with a broad Marginal Risk remaining
valid.

...Lower Missouri Valley to Southeastern Virginia and Eastern North
Carolina...

A targeted Slight Risk remains centered over eastern North
Carolina and extends into southeastern Virginia. Convection will
develop ahead of a slow-moving cold front that will be dropping
south into a very moist (PWs 2+ inches) and unstable (MUCAPE >
2000 J/kg) environment, while some modest right-entrance region
upper jet forcing will offer some enhanced ascent. Heavy totals
appear likely, with both the HREF and REFS showing high
neighborhood probabilities for some 2 to 4 inch totals within the
Slight Risk area, mainly between the Hampton Roads area and
Morehead City. There was a minor northward adjustment of the
Marginal and Slight Risk areas across central Virginia to account
for the latest model trends compared to the overnight issuance.

Less organized activity is expected back along the front extending
across the southern Appalachians, Tennessee Valley, and parts of
the lower Ohio, mid Mississippi, and lower Missouri valleys. While
widespread heavy totals are not expected, the moisture-rich
environment (PWs 1.75-2 inches) is expected to support storms
capable of producing localized heavy amounts and isolated runoff
concerns.

...Eastern Dakotas into the upper Mississippi Valley...

A shortwave moving off of the top of the western U.S. ridge will
interact with a frontal system advancing through the northern
Plains into the Upper Midwest. An amplifying west-southwesterly
low level jet will support increasing PWs (1.75-2 inches) and
instability ahead of a frontal boundary. The models have trended the
axis of heaviest rainfall farther north into central and northern
Minnesota, and therefore the existing Marginal Risk area has been
extended to the Minnesota/Canada border. Any new burn scar areas
will be more susceptible to potential flood issues.

...Eastern Gulf Coast into the Southeast...

Newly formed Tropical Depression Two is idling in place across the
northeastern Gulf about 150 miles south of Panama City, Florida.
Recent radar imagery indicates the core of convection and heaviest
rainfall well offshore, and the latest CAM guidance suite
suggests this will remain the case going through the remainder of
the afternoon and into tonight. However, some heavier amounts
along the west coast of Florida are likely with outer feeder bands
and could lead to some localized instances of flooding where
training convection develops. Therefore, the Marginal Risk was
maintained from the overnight issuance.

An axis of enhanced low level convergence and pooling moisture to
the north is still expected be a focus for diurnal storms capable
of producing heavy rainfall rates. Therefore, a Marginal Risk was
maintained from the central Gulf Coast northward into the Tennessee
Valley. Recent CAM guidance indicate localized totals of 1 to 3 inches
across portions of this region through early evening where the most
persistent convection develops.

Pereira/Hamrick

Day 2
Valid 12Z Mon Jul 20 2026 - 12Z Tue Jul 21 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
THE DESERT SOUTHWEST AND NORTH CAROLINA...

...Southwest and Great Basin...

Mid-level energy moving west of the region, and dry air advection
from the south will begin to diminish the heavy rainfall and flash
flooding threat over West Texas. However farther west, the
monsoonal moisture plume will remain firmly in place, ensuring
another day of efficient rainfall production over portions of the
Southwest and Great Basin. Models show the upper high originally
centered over Utah and Colorado beginning to slide southeast,
allowing moisture and energy to spread northwest into the Great
Basin and along the western slopes of the Sierra Nevada, raising
the potential for increasing storm activity and isolated runoff
concerns in those areas.

The greater heavy rainfall and flash flooding threat will remain
focused from southwestern New Mexico and southeastern Arizona
northwestward along the Mogollon Rim into northwestern Arizona.
This is expected to be the focus for better synoptic forcing and
greater instability, supporting intense short-duration rain rates
that will elevate the risk for flash flooding, especially in areas
of complex terrain, dry washes, and burn scars. For the 19Z Update,
a minor westward extension of the Slight Risk was made across
northwestern Arizona to the Lake Mead area.

...Upper Great Lakes...

An amplifying upper trough supported by energy diving out of
Canada will advance from the upper Mississippi Valley to the upper
Great Lakes. Strong southwesterly to west-southwesterly low level
inflow will continue to sustain deep moisture ahead of the cold
front and across the advancing warm front. This moisture along with
strong forcing, produced in part by left-exit region upper jet
dynamics, will generate organized convection capable of producing
rainfall rates of 1-2 in/hr. Fast storm motions should limit the
overall heavy accumulation and flash flooding threat. However,
localized short-term training could raise at least some isolated
concerns. No changes were needed here for the updated Day 2
outlook.

...North Carolina and Southern Virginia...

A lingering boundary and corresponding pool of deep moisture
convergence, with PWs generally near or slightly above 2 inches,
will support additional thunderstorms capable of producing heavy
downpours. There has been a trend for heavier QPF in today's
guidance across much of central and eastern North Carolina, and
after consultation with the local WFOs, a Slight Risk area has been
introduced for this area. Heavy rainfall expected through Sunday
night will lead to reduced FFGs and more saturated soils that will
be more prone to flooding issues.

...Gulf Coast...

The models continue to show the footprint of the heaviest amounts
associated with Tropical Depression Two over the northern Gulf
remaining mostly offshore. The Marginal Risk has been maintained along
the coast from West Florida near Tampa, to southeastern Louisiana,
which encompasses areas generally along the Interstate 10 corridor,
with the highest totals likely near the Big Bend of Florida. Moisture
pooling along an axis of enhanced low level convergence northwest
of the circulation may extend the threat for heavy rainfall further
inland into the far lower Mississippi Valley. If there are
northward trends in later model cycles, it is possible that a
Slight Risk could eventually be needed for portions of this outlook
area.

Pereira/Hamrick

Day 3
Valid 12Z Tue Jul 21 2026 - 12Z Wed Jul 22 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHWEST AND EASTERN KENTUCKY TO THE DELMARVA...

...Southwest to the northern Rockies...

Models show the upper high continuing to shift east as an upper
trough begins to drift into the Pacific Northwest. This will allow
the monsoon moisture plume to spread farther north, with moisture
anomalies over 3 standard deviations above normal extending as far
north as the northern Rockies. This will support increasing
convective development with isolated flash flooding concerns as far
north as southwestern Montana and southern Idaho.

However, the greater heavy rainfall and flash flooding threat is
expected to remain centered over western New Mexico, central and
northern Arizona, and southern Utah. Guidance shows a fairly well-
defined shortwave moving around the western periphery of the upper
high, which along with PWs over 1.5 inches in many spots, and
highly sensitive soils, will likely generate additional widespread
storm coverage and flash flooding concerns. Given the synoptic
setup and anomalous moisture, this can be considered a high-end
Slight for parts of Arizona and a potential upgrade to Moderate
Risk may be required in future outlooks if models trend higher.
No major changes were needed for this region in the 20Z update.

...Ohio Valley to the Mid-Atlantic...

Upon examination of the 12Z model and CAM guidance suite, there is
a general upward trend in expected QPF across more of the region to
include the central Appalachians and Blue Ridge Mountains, and
therefore the two existing Slight Risk areas were merged into a
single larger area extending from eastern Kentucky to the DelMarVa.
Moist soils and flood-prone mountain terrain are likely to
contribute to the flash flood threat across this region. Deep
moisture (PWs around 2 inches) will fuel showers and storms ahead
of a strong cold front advancing southeast across the region. These
storms will be capable of producing 1-2 in/hr rainfall rates,
raising flash flooding concerns. The Marginal Risk area was also
extended northeastward to include more of central New England where
some of the deterministic guidance supports the idea for some 1-2
inch rainfall maxima.

Farther east across the Mid-Atlantic, strengthening southeasterly
flow ahead of the system moving through the Ohio Valley will
transport an anomalous moisture plume into a region of strong
ascent. This combination will support increasing coverage of
showers and storms capable of producing heavy rainfall. While the
exact spatial coverage of heaviest amounts remains somewhat
uncertain, portions of the the more flood-prone urbanized I-95
corridor could be impacted, warranting the continuance of the Slight
Risk area.

...Gulf Coast...

With the heavy rainfall footprint associated with Tropical
Depression Two remaining offshore in most of the guidance, we
continued to maintain only a Marginal Risk for the central/eastern
Gulf Coast that is mainly confined to the Interstate 10 corridor
and to the coast. Any northward trends will need to be monitored in
case the heavier core of rainfall reaches the coast, which could
necessitate the need for a future Slight Risk.

Pereira/Hamrick

Day 4 and Day 5

Valid 12Z Wed Jul 22 2026 - 12Z Fri Jul 24 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ALONG PORTIONS OF
THE SOUTHEAST US AND CENTRAL/WESTERN GULF COAST...

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE INTERMOUNTAIN WEST AND CENTRAl PLAINS ON WEDNESDAY...

2030Z Discussion...
Introduced a Slight Risk area along the central Gulf coast on
Tuesday and central to western Gulf coast on Wednesday along the
path of Tropical Depression 2. Given the amount of shear across the system...the maximum rainfall amounts be displaced to the south of
the system which would place it in very narrow corridor along the
coast or placed off-shore. But the on-shore fetch of moisture
around the center is enough to warrant a Slight for the time being.
Until the degree of ridging to the north is resolved...and how
much dry air that feeds into the system or its influences on the
track...there is too much uncertainty to highlight any more than a
Slight Risk area at this point.

Otherwise...introduced a SLight Risk area over portions of the
Central US as shortwave energy ejecting from the Rockies interacts
with a low level boundary to produce convection in an anomalously
moist airmass capable of supporting locally heavy rainfall.

No other changes needed elsewhere.

Bann

Previous Discussion...

...Tidewater Region of Virginia and the Carolinas...

A slow-moving cold front pushing southeast out of the Mid-Atlantic
on Wednesday is likely to continue slowing down its forward speed
as it approaches the Tidewater Region of Virginia and the Carolinas
on Wednesday. Meanwhile, plentiful tropical moisture will be drawn northeastward from the tropical system that will likely be
meandering somewhere near the Louisiana coast on Wednesday. This
moisture will ride northeastward ahead of the front, spiking PWATs
above 2.25 inches over this entire region. The result of a strong
but slow-moving front, well above normal amounts of moisture, and
upper level support in the form of a deep trough over the Northeast
supporting the surface front from behind/north will make for a
nearly ideal scenario for training and backbuilding storms from the
afternoon through the evening.

This Day 4/Wednesday period is likely to be the fourth consecutive
day that showers and thunderstorms have been dropping locally very
heavy rain and multiple-inch rainfall totals somewhere in and
around eastern North Carolina. The front will act to greatly expand
the footprint of heavy rainfall in this area. Since soils are all
but certain to be nearly saturated in this area by Wednesday, flash
flooding concerns continue to increase. Thus, a higher-end Slight
was introduced with this update from Raleigh east, and from
Wilmington north through the Hampton Roads area. It's probable that
should the trends continue to increase both with the expected
rainfall on Wednesday, and the prior days' rainfall in this same
region, that a Moderate Risk upgrade will be needed with future
updates.

By Day 5/Thursday, the front will sag a hair bit further south,
likely sparing the Raleigh and Hampton Roads metros from much
additional rainfall, but instead concentrating the heaviest rains
from the Outer Banks southwest down the coast through Wilmington
and including Charleston, SC in heavy rainfall. The ERO thus was
started this morning with a Slight Risk for this area. Of course,
even just a small increase in forward speed will push the front up
to the coast, which would then concentrate all of the heaviest
rains off the coast, making the Slight Risk an over-forecast.
However, any slower/westward positioning of the front will make
for a 5th consecutive day of heavy rains in eastern North
Carolina...meaning the Slight Risk would be an under-forecast.
Thus, the Slight represents the "happy medium" of these scenarios
and fits best with the current rainfall forecast in the area for
Thursday.

...Intermountain West...

A Slight Risk upgrade was introduced with this update for a portion
of the Intermountain West on Wednesday. The area highlighted
includes all of southeastern Idaho, much of western Wyoming outside
of Yellowstone, as well as far northern Utah and the northwestern
corner of Colorado. Well above normal amounts of atmospheric
moisture to the tune of up to 4 sigma above normal, and PWATs
locally exceeding 1.25 inches will be in place across this region.
An approaching longwave trough will direct a strong shortwave
northeastward during the afternoon hours. This will result in
widespread shower and thunderstorm activity over this area.
Topographic interaction with the storms will locally enhance
rainfall rates, while also supporting impactful flash flooding as
the rain water races down the slopes of the mountains. Due to the
abundant moisture available, the storms will not only be numerous,
but capable of 2 inch/hour rainfall rates with the strongest cores,
a phenomenon not often seen in this part of the country.

Wegman

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!53UNXpQCsCqtNo7iw7sMghJ7wO6_jZdt_G-JvP8M8n28C2JL1I3uAve2CmWyK0D8UDqExyRqUOJNlnoQzNK1RSPWWq8$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!53UNXpQCsCqtNo7iw7sMghJ7wO6_jZdt_G-JvP8M8n28C2JL1I3uAve2CmWyK0D8UDqExyRqUOJNlnoQzNK1EzV4u6U$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!53UNXpQCsCqtNo7iw7sMghJ7wO6_jZdt_G-JvP8M8n28C2JL1I3uAve2CmWyK0D8UDqExyRqUOJNlnoQzNK1ruLlsXg$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Jul 20 08:27:34 2026

FOUS30 KWBC 200827
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
427 AM EDT Mon Jul 20 2026

Day 1
Valid 12Z Mon Jul 20 2026 - 12Z Tue Jul 21 2026

...THERE ARE SLIGHT RISKS OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHWEST AS WELL AS FOR EASTERN NORTH CAROLINA...

...Southwest...

Very few changes were needed with the inherited Slight Risk area
from far west Texas, southwestern New Mexico, and much of Arizona
with this update. Monsoonal moisture will stream north off the Gulf
of California and into the Four Corners region today. With peak
heating, afternoon thunderstorms are expected over much of the
Slight Risk area. Much of the area has seen afternoon thunderstorms
causing localized flash flooding in recent days, and the same
pattern continues today. The threat further east will be driven by
a subtle shortwave disturbance retrograding west along the Mexican
border. This will allow for greater longitudinal spread of storms
to include far west Texas. MUCAPE values will be between 1,000 and
2,000 J/kg across much of the region, as PWATs rise above 1.5
inches in some areas. Between the aforementioned disturbance and
local topography, expect widely scattered instances of flash
flooding where the storms today are most persistent.

...Eastern North Carolina...

A stalled out front along the VA/NC border at the start of the day
will retreat northward in the form of a warm front as deep tropical
moisture advects northeastward from the tropical depression in the
Gulf. The front will provide enough forcing across much of eastern
North Carolina to allow for a renewed round of widespread showers
and thunderstorms in the area. Soils remain generally dry over most
of the area, despite storms impacting some of eastern North
Carolina yesterday. Due to the well above normal amounts of
moisture for the storms to work with, as well as the front
providing some forcing, the Slight Risk was expanded west to
overlap some of the areas of North Carolina that are being impacted
by storms currently, generally just east of Charlotte. Otherwise,
the threat remains similar to yesterday, so few changes were needed
with this update.

...Gulf Coast...

The outermost northern and western periphery of Tropical Depression
Two continues to impact much of the Gulf Coast of Florida, through
the Panhandle, and over to southeastern Louisiana. The storms are
few and far between, but ample moisture associated with a
developing tropical cyclone is allowing for any storms to have the
potential to produce multiple inch per hour rates. Regardless, the
center remains far enough offshore, with drier air aloft working to significantly cut down on the overall coverage of storms.
Considering the dry soils and high FFGs typical of the immediate
Gulf Coast, even periods of heavy rain should only result in
isolated instances of flash flooding. Thus, the inherited Marginal
remains in place.

...Midwest...

The Marginal Risk across much of the Midwest and upper Great Lakes
also remains largely the same today. There remains considerable
uncertainty as to coverage of storms impacting the area today into
tonight. It appears the most likely areas to be impacted stretches
from the southeastern corner of Minnesota south through eastern
Iowa and into northeastern Missouri. However, even in this area,
dry soils and the height of the growing season should allow most of
the rain expected to water the crops in the region, with minimal
threat for flash flooding. Thus, few changes were needed with this
update.

Wegman

Day 2
Valid 12Z Tue Jul 21 2026 - 12Z Wed Jul 22 2026

...THERE ARE SLIGHT RISKS OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
ARIZONA AND UTAH, AS WELL AS THE UPPER OHIO VALLEY AND INTO THE
MID-ATLANTIC...

...Arizona into Utah...

Increasing monsoonal moisture, particularly into southern Arizona
will combine with an approaching upper level shortwave trough to
further increase convective converage across portions of the
Southwest on Tuesday as compared with previous days. The
introduction of a northwestward-moving shortwave trough will allow
the convective activity to wane over eastern New Mexico and west
Texas, and instead promote more activity into eastern Nevada, Utah,
and portions of Colorado and Wyoming. Numerous highly flash-flood
prone slot canyons, dry washes, and rocky soils will allow the many
storms that form over the region to cause scattered instances of
flash flooding. The Slight Risk area was expanded north to include
much of Utah and into eastern Nevada for this region. The greatest
convective coverage and most impactful flash flooding is expected
over portions of Arizona and the boot heel of New Mexico. A
higher-end Slight remains in effect along the Mogollon Rim, but has
been expanded to the Mexico border along the AZ/NM border with this
update.

...Upper Ohio Valley through the Mid-Atlantic...

A strong cold front pushing south across the Midwest will run into
plentiful tropical moisture being drawn north from Tropical
Depression 2 in the Gulf. The front will act as a catalyst for
numerous segments of mostly fast moving thunderstorms across the
Mid-Atlantic and Ohio Valley on Tuesday. With PWATs ahead of the
front over 2.25 inches in some instances, and in most areas above 2
inches, the storms will have plentiful juice to work with, allowing
for heavy rainfall to impact most areas from the central and
northern Appalachians to the urban I-95 corridor from Richmond up
through Boston. The fast moving nature of the storms should mean
most areas have severe concerns as higher priority than flash
flooding. However, it's likely that backbuilding and training
storms on the book ends of any segments could cause widely
scattered instances of flash flooding. Thus, the Slight Risk
inherited over much of the Mid-Atlantic remains in place with few
changes.

...Gulf Coast...

Tropical Depression 2 is expected to gradually drift west, with the
center following near the Gulf Coast. All of the guidance suggests
that northerly shear and dry air entrainment will push any
meaningful associated heavy rainfall south of the center over the
Gulf, leaving very little rainfall to impact the immediate Gulf
Coast. Thus, despite being a tropical cyclone with local PWATs up
to 2.5 inches, the distinctive lack of rainfall for most land
areas, especially away from the immediate coast remains an unusual
feature with TD2. The Marginal Risk in place over most of the
northern Gulf Coast from the Florida Panhandle west through
southeast Louisiana remains in place with few changes.

Wegman

Day 3
Valid 12Z Wed Jul 22 2026 - 12Z Thu Jul 23 2026

...THERE ARE SLIGHT RISKS OF EXCESSIVE RAINFALL FOR THE CAROLINAS,
PORTIONS OF THE INTERMOUNTAIN WEST, AND THE CENTRAL GULF COAST...

...Carolinas into Southeastern Virginia...

A strong cold front that impacted much of the Mid-Atlantic on
Tuesday will stall out over central Virginia on Wednesday. Ahead of
the front, abundant Gulf moisture will continue streaming
northeastward from Tropical Depression 2, likely to be centered
south of the Mississippi Delta. Since the front will remain strong,
and the moisture will remain well above normal for the Carolinas,
as PWATs spike above 2.25 inches at times, the front will act as a
train track for numerous training and backbuilding thunderstorms.
The focus for these storms will be where the front interacts with
the deepest moisture, which is expected from central North Carolina
northeast through the Tidewater of Virginia.

This area should get a break in the rain on Day 2/Tuesday, such
that by the time the heaviest rains impact NC and VA on Wednesday,
some draining from prior days' storms should work to limit the
flash flooding risk somewhat. Thus, for now the area remains in a
higher end Slight. The forecast rainfall will continue to be
monitored as a Moderate Risk upgrade remains a possibility.

...Central Gulf Coast...

Tropical Depression 2 is expected to be drifting west to the south
of Louisiana on Wednesday. The conditions impacting the system will
remain much the same on Wednesday as on prior days. Northerly shear
will remain in place, pushing most of the associated convection
south of the circulation center, keeping nearly all of the heaviest
rains over the Gulf. Only a tiny fraction of the storm's overall
rainfall will impact land areas, with the best chance expected
along the immediate Gulf Coast of southeastern Louisiana. The
inherited Slight Risk was trimmed to just the immediate coast,
dropping the threat for metro New Orleans, in coordination with
LIX/Slidell, LA forecast office. Of course, trends in the storm
will continue to be monitored, as subtle changes in the environment
around the storm could result in large changes in the rainfall
forecast.

...Intermountain West...

The combination of well above normal moisture across much of the
intermountain West on Wednesday, strong upper level disturbances
tracking northeastward ahead of a longwave trough over the Pacific
Northwest, and numerous mountain ranges will all work to promote a
much higher than normal flash flooding potential over the area from
the 4 Corners north through much of southeastern Idaho. The Slight
Risk for Idaho and Wyoming was expanded south due to yet another
day of expected showers and thunderstorms impacting the highly
flash flooding prone areas of Utah and western Colorado. The
greatest rainfall totals are likely into northwestern Wyoming, from
Yellowstone south. Few changes were needed north of Wyoming's
southern border.

Wegman

Day 4 and Day 5

Valid 12Z Thu Jul 23 2026 - 12Z Sat Jul 25 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
CENTRAL PLAINS TO LOWER MISSOURI VALLEY, THE CENTRAL TO WESTERN
GULF COAST, AND THE EASTERN CAROLINAS ON DAY 4...

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
LOWER MISSOURI AND MID MISSISSIPPI VALLEYS, AND THE EASTERN
CAROLINAS ON DAY 5...

...Southeast...
A moisture-laden front will continue to sink slowly south across
the region. While the overnight guidance continues to present
differences on the timing of the front and corresponding
precipitation, there remains a strong signal for additional heavy
amounts impacting parts of the region, especially for portions of
the Carolinas. PWs remaining around 2.25 inches along with periods
of enhanced ascent will raise the threat for additional heavy
amounts most likely centered over eastern North Carolina into
northeast South Carolina Thursday into early Friday. Due in part to
model differences and forecast uncertainty, maintained a Slight
Risk. However, this has the potential to be a second day in-a-row,
and the fourth day this week for heavy rains impacting parts of
the region. Therefore, if forecast confidence increases and the
signal for a multi-day heavy rainfall event holds, future upgrades
may be required.

For Friday into early Saturday, it remains a question
whether the front will continue to push south, bringing drier
conditions into the Carolinas as the GFS/UKMET indicate, or
continue to hang up well to the north as shown by the ECMWF and
Canadian. Opted for a Slight Risk on for the Day 5, centered
similar to the Day 4 area, which presents a compromise between the
two camps and lined up with the higher probabilities from the most
recent ECENS.

...Gulf Coast...
Shear across Tropical Depression Two is expected to keep the
heaviest rainfall amounts associated with the system mostly south
of the center and offshore. However, cannot rule out the threat for
onshore flow supporting some locally heavy amounts along the coast,
especially if the trends support a stronger system and more
northerly track. Therefore, the a Slight Risk was maintained along
the Louisiana to the upper Texas Coast on Day 4.

A Marginal Risk was drawn for Day 5 from the upper Texas Coast
inland toward south-central Texas, where heavy amounts are
possible if the storm remains organized and continues to track
west.

...Central Plains to the Mid Mississippi Valley...
Models continue to show a well-defined shortwave sliding southeast
off of the top of the western U.S. ridge through the northern
Plains and into the mid Mississippi Valley on Day 4. Organized
heavy rain may develop late Thursday into early Friday as this
energy interacts with a deepening moisture pool fed by a
strengthening southwesterly jet. A Slight Risk was maintained on
Day 4 over parts of southeastern Nebraska into adjacent parts of
Kansas, Iowa, and Missouri, where models indicate the deepest
moisture, better forcing and greater potential for localized
training will center. Storms continuing through Friday morning and
possibly redeveloping later in the day downstream will extend the
threat across across a greater part of the mid Mississippi Valley
on Day 5.

...Southwest/Great Basin/Central and Southern Rockies...
Monsoon moisture will continue to fuel diurnal activity, however
the footprint is expected to diminish especially by Day 5 as
moisture anomalies drop off and heights build across the Southwest.

Pereira

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!_mHg-4pBIXrkDdgmVnHKcLlUBbUhXHzczMx3b3I_kIXSbDyeUvRYydV-Ea6Y38TZamO2XR_N_QYWBfFzuQCq4AauEqE$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!_mHg-4pBIXrkDdgmVnHKcLlUBbUhXHzczMx3b3I_kIXSbDyeUvRYydV-Ea6Y38TZamO2XR_N_QYWBfFzuQCqpy5kfeE$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!_mHg-4pBIXrkDdgmVnHKcLlUBbUhXHzczMx3b3I_kIXSbDyeUvRYydV-Ea6Y38TZamO2XR_N_QYWBfFzuQCqGjcHxjQ$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Jul 20 16:02:40 2026

FOUS30 KWBC 201602
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1202 PM EDT Mon Jul 20 2026

Day 1
Valid 16Z Mon Jul 20 2026 - 12Z Tue Jul 21 2026

...THERE ARE SLIGHT RISKS OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHWEST AND NORTH CAROLINA...

...Southwest...

16Z Update...little change, more Marginal in western CO.
Monsoonal moisture continues to stream across the Southwest into
the Great Basin with renewed diurnal convective coverage again
today. The eastern end of the threat area is bounded by a shortwave
low over west Texas. Elevated moisture with PW of 2 to 2.5
standard deviations above normal and limited cloud cover from
overnight allows good coverage of convection. Focus of heavies
along the Mogollon Rim, southeast AZ and southern NM. West Texas is
less certain for needing a Slight given ongoing clouds/precip this
morning.

...Southern Mid-Atlantic to southern Appalachians...

A warm front on leaving edge of deep tropical moisture plume
extending northeastward from the tropical depression in the Gulf.
The front will provide enough forcing across much of eastern North
Carolina to allow for a renewed round of widespread showers and
thunderstorms in the area. Soils remain generally dry over most of
the area, despite storms impacting some of eastern North Carolina
yesterday. Above normal moisture for the storms to work and the
front providing some forcing warrants continuation of the Slight
Risk. Trimmed southern NC from the Slight given consensus in the
12Z HREF/REFS.

...Gulf Coast...

The outermost western periphery of Tropical Depression Two
continues to impact the Gulf Coast of Florida, through the
Panhandle into southern Georgia, and over to southeastern
Louisiana. Banding is occurring, so localized multiple inch per
hour rates. Regardless, the center remains far enough offshore,
with drier air aloft working to significantly cut down on the
overall coverage of storms. Considering the dry soils and high FFGs
typical of the immediate Gulf Coast, even periods of heavy rain
should only result in isolated instances of flash flooding. Thus,
there was little change to the Marginal Risk area.

...Midwest...

The Marginal Risk across much of the Midwest and upper Great Lakes
also remains largely intact with updated progression for ongoing
activity. There remains considerable uncertainty as to coverage of
storms impacting the area today into tonight. It appears the most
likely areas to be impacted this afternoon/tonight are from central
Iowa east across northern Illinois. Dry soils highlight this area,
so this being the height of the growing season should mitigate the
flash flood risk.

Jackson

Day 2
Valid 12Z Tue Jul 21 2026 - 12Z Wed Jul 22 2026

...THERE ARE SLIGHT RISKS OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
ARIZONA AND UTAH, AS WELL AS THE UPPER OHIO VALLEY AND INTO THE
MID-ATLANTIC...

...Arizona into Utah...

Increasing monsoonal moisture, particularly into southern Arizona
will combine with an approaching upper level shortwave trough to
further increase convective converage across portions of the
Southwest on Tuesday as compared with previous days. The
introduction of a northwestward-moving shortwave trough will allow
the convective activity to wane over eastern New Mexico and west
Texas, and instead promote more activity into eastern Nevada, Utah,
and portions of Colorado and Wyoming. Numerous highly flash-flood
prone slot canyons, dry washes, and rocky soils will allow the many
storms that form over the region to cause scattered instances of
flash flooding. The Slight Risk area was expanded north to include
much of Utah and into eastern Nevada for this region. The greatest
convective coverage and most impactful flash flooding is expected
over portions of Arizona and the boot heel of New Mexico. A
higher-end Slight remains in effect along the Mogollon Rim, but has
been expanded to the Mexico border along the AZ/NM border with this
update.

...Upper Ohio Valley through the Mid-Atlantic...

A strong cold front pushing south across the Midwest will run into
plentiful tropical moisture being drawn north from Tropical
Depression 2 in the Gulf. The front will act as a catalyst for
numerous segments of mostly fast moving thunderstorms across the
Mid-Atlantic and Ohio Valley on Tuesday. With PWATs ahead of the
front over 2.25 inches in some instances, and in most areas above 2
inches, the storms will have plentiful juice to work with, allowing
for heavy rainfall to impact most areas from the central and
northern Appalachians to the urban I-95 corridor from Richmond up
through Boston. The fast moving nature of the storms should mean
most areas have severe concerns as higher priority than flash
flooding. However, it's likely that backbuilding and training
storms on the book ends of any segments could cause widely
scattered instances of flash flooding. Thus, the Slight Risk
inherited over much of the Mid-Atlantic remains in place with few
changes.

...Gulf Coast...

Tropical Depression 2 is expected to gradually drift west, with the
center following near the Gulf Coast. All of the guidance suggests
that northerly shear and dry air entrainment will push any
meaningful associated heavy rainfall south of the center over the
Gulf, leaving very little rainfall to impact the immediate Gulf
Coast. Thus, despite being a tropical cyclone with local PWATs up
to 2.5 inches, the distinctive lack of rainfall for most land
areas, especially away from the immediate coast remains an unusual
feature with TD2. The Marginal Risk in place over most of the
northern Gulf Coast from the Florida Panhandle west through
southeast Louisiana remains in place with few changes.

Wegman

Day 3
Valid 12Z Wed Jul 22 2026 - 12Z Thu Jul 23 2026

...THERE ARE SLIGHT RISKS OF EXCESSIVE RAINFALL FOR THE CAROLINAS,
PORTIONS OF THE INTERMOUNTAIN WEST, AND THE CENTRAL GULF COAST...

...Carolinas into Southeastern Virginia...

A strong cold front that impacted much of the Mid-Atlantic on
Tuesday will stall out over central Virginia on Wednesday. Ahead of
the front, abundant Gulf moisture will continue streaming
northeastward from Tropical Depression 2, likely to be centered
south of the Mississippi Delta. Since the front will remain strong,
and the moisture will remain well above normal for the Carolinas,
as PWATs spike above 2.25 inches at times, the front will act as a
train track for numerous training and backbuilding thunderstorms.
The focus for these storms will be where the front interacts with
the deepest moisture, which is expected from central North Carolina
northeast through the Tidewater of Virginia.

This area should get a break in the rain on Day 2/Tuesday, such
that by the time the heaviest rains impact NC and VA on Wednesday,
some draining from prior days' storms should work to limit the
flash flooding risk somewhat. Thus, for now the area remains in a
higher end Slight. The forecast rainfall will continue to be
monitored as a Moderate Risk upgrade remains a possibility.

...Central Gulf Coast...

Tropical Depression 2 is expected to be drifting west to the south
of Louisiana on Wednesday. The conditions impacting the system will
remain much the same on Wednesday as on prior days. Northerly shear
will remain in place, pushing most of the associated convection
south of the circulation center, keeping nearly all of the heaviest
rains over the Gulf. Only a tiny fraction of the storm's overall
rainfall will impact land areas, with the best chance expected
along the immediate Gulf Coast of southeastern Louisiana. The
inherited Slight Risk was trimmed to just the immediate coast,
dropping the threat for metro New Orleans, in coordination with
LIX/Slidell, LA forecast office. Of course, trends in the storm
will continue to be monitored, as subtle changes in the environment
around the storm could result in large changes in the rainfall
forecast.

...Intermountain West...

The combination of well above normal moisture across much of the
intermountain West on Wednesday, strong upper level disturbances
tracking northeastward ahead of a longwave trough over the Pacific
Northwest, and numerous mountain ranges will all work to promote a
much higher than normal flash flooding potential over the area from
the 4 Corners north through much of southeastern Idaho. The Slight
Risk for Idaho and Wyoming was expanded south due to yet another
day of expected showers and thunderstorms impacting the highly
flash flooding prone areas of Utah and western Colorado. The
greatest rainfall totals are likely into northwestern Wyoming, from
Yellowstone south. Few changes were needed north of Wyoming's
southern border.

Wegman

Day 4 and Day 5

Valid 12Z Thu Jul 23 2026 - 12Z Sat Jul 25 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
CENTRAL PLAINS TO LOWER MISSOURI VALLEY, THE CENTRAL TO WESTERN
GULF COAST, AND THE EASTERN CAROLINAS ON DAY 4...

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
LOWER MISSOURI AND MID MISSISSIPPI VALLEYS, AND THE EASTERN
CAROLINAS ON DAY 5...

...Southeast...
A moisture-laden front will continue to sink slowly south across
the region. While the overnight guidance continues to present
differences on the timing of the front and corresponding
precipitation, there remains a strong signal for additional heavy
amounts impacting parts of the region, especially for portions of
the Carolinas. PWs remaining around 2.25 inches along with periods
of enhanced ascent will raise the threat for additional heavy
amounts most likely centered over eastern North Carolina into
northeast South Carolina Thursday into early Friday. Due in part to
model differences and forecast uncertainty, maintained a Slight
Risk. However, this has the potential to be a second day in-a-row,
and the fourth day this week for heavy rains impacting parts of
the region. Therefore, if forecast confidence increases and the
signal for a multi-day heavy rainfall event holds, future upgrades
may be required.

For Friday into early Saturday, it remains a question
whether the front will continue to push south, bringing drier
conditions into the Carolinas as the GFS/UKMET indicate, or
continue to hang up well to the north as shown by the ECMWF and
Canadian. Opted for a Slight Risk on for the Day 5, centered
similar to the Day 4 area, which presents a compromise between the
two camps and lined up with the higher probabilities from the most
recent ECENS.

...Gulf Coast...
Shear across Tropical Depression Two is expected to keep the
heaviest rainfall amounts associated with the system mostly south
of the center and offshore. However, cannot rule out the threat for
onshore flow supporting some locally heavy amounts along the coast,
especially if the trends support a stronger system and more
northerly track. Therefore, the a Slight Risk was maintained along
the Louisiana to the upper Texas Coast on Day 4.

A Marginal Risk was drawn for Day 5 from the upper Texas Coast
inland toward south-central Texas, where heavy amounts are
possible if the storm remains organized and continues to track
west.

...Central Plains to the Mid Mississippi Valley...
Models continue to show a well-defined shortwave sliding southeast
off of the top of the western U.S. ridge through the northern
Plains and into the mid Mississippi Valley on Day 4. Organized
heavy rain may develop late Thursday into early Friday as this
energy interacts with a deepening moisture pool fed by a
strengthening southwesterly jet. A Slight Risk was maintained on
Day 4 over parts of southeastern Nebraska into adjacent parts of
Kansas, Iowa, and Missouri, where models indicate the deepest
moisture, better forcing and greater potential for localized
training will center. Storms continuing through Friday morning and
possibly redeveloping later in the day downstream will extend the
threat across across a greater part of the mid Mississippi Valley
on Day 5.

...Southwest/Great Basin/Central and Southern Rockies...
Monsoon moisture will continue to fuel diurnal activity, however
the footprint is expected to diminish especially by Day 5 as
moisture anomalies drop off and heights build across the Southwest.

Pereira

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!5R267HLYXVPXXRPFVnmoG4JvEZCkGBNazZ4vjS7s4gbnvlOii22uf8eIRdbA44QnGxZzTPMLodvRVgpUhZfU6xYsHXg$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!5R267HLYXVPXXRPFVnmoG4JvEZCkGBNazZ4vjS7s4gbnvlOii22uf8eIRdbA44QnGxZzTPMLodvRVgpUhZfUJLav4fc$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!5R267HLYXVPXXRPFVnmoG4JvEZCkGBNazZ4vjS7s4gbnvlOii22uf8eIRdbA44QnGxZzTPMLodvRVgpUhZfUfAf4GgM$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Jul 20 20:24:48 2026

FOUS30 KWBC 202024
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
424 PM EDT Mon Jul 20 2026

Day 1
Valid 16Z Mon Jul 20 2026 - 12Z Tue Jul 21 2026

...THERE ARE SLIGHT RISKS OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHWEST AND NORTH CAROLINA...

...Southwest...

16Z Update...little change, more Marginal in western CO.
Monsoonal moisture continues to stream across the Southwest into
the Great Basin with renewed diurnal convective coverage again
today. The eastern end of the threat area is bounded by a shortwave
low over west Texas. Elevated moisture with PW of 2 to 2.5
standard deviations above normal and limited cloud cover from
overnight allows good coverage of convection. Focus of heavies
along the Mogollon Rim, southeast AZ and southern NM. West Texas is
less certain for needing a Slight given ongoing clouds/precip this
morning.

...Southern Mid-Atlantic to southern Appalachians...

A warm front on leaving edge of deep tropical moisture plume
extending northeastward from the tropical depression in the Gulf.
The front will provide enough forcing across much of eastern North
Carolina to allow for a renewed round of widespread showers and
thunderstorms in the area. Soils remain generally dry over most of
the area, despite storms impacting some of eastern North Carolina
yesterday. Above normal moisture for the storms to work and the
front providing some forcing warrants continuation of the Slight
Risk. Trimmed southern NC from the Slight given consensus in the
12Z HREF/REFS.

...Gulf Coast...

The outermost western periphery of Tropical Depression Two
continues to impact the Gulf Coast of Florida, through the
Panhandle into southern Georgia, and over to southeastern
Louisiana. Banding is occurring, so localized multiple inch per
hour rates. Regardless, the center remains far enough offshore,
with drier air aloft working to significantly cut down on the
overall coverage of storms. Considering the dry soils and high FFGs
typical of the immediate Gulf Coast, even periods of heavy rain
should only result in isolated instances of flash flooding. Thus,
there was little change to the Marginal Risk area.

...Midwest...

The Marginal Risk across much of the Midwest and upper Great Lakes
also remains largely intact with updated progression for ongoing
activity. There remains considerable uncertainty as to coverage of
storms impacting the area today into tonight. It appears the most
likely areas to be impacted this afternoon/tonight are from central
Iowa east across northern Illinois. Dry soils highlight this area,
so this being the height of the growing season should mitigate the
flash flood risk.

Jackson

Day 2
Valid 12Z Tue Jul 21 2026 - 12Z Wed Jul 22 2026

...THERE ARE SLIGHT RISKS OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE SOUTHWEST AND THE MID-ATLANTIC TO THE OHIO VALLEY...

...Intermountain West...

Monsoonal moisture continues to arrive over the Southwest from the
sub-tropical Pacific around a mid-level high centered over
Colorado. A shortwave trough will track from southwest NM into
eastern AZ which will promote increased convective coverage over
both AZ and UT into NV. The Slight Risk area was further expanded
to include most of UT through central NV. The greatest convective
coverage and most impactful flash flooding is still expected from
southeast AZ up through the Mogollon Rim to the Grand Canyon which
is considered a more "enhanced" Slight Risk. A fair amount of
convective coverage tonight over AZ may cause some opaque stratus
to persist into Tuesday which could at least locally disrupt the
diurnal trend in activity.

The PW anomaly reaches 4 standard deviations above normal over the
Sierra Nevada on Tuesday. This should promote vigorous diurnal
convection up the High Sierra to Lake Tahoe. A Slight Risk may be
warranted, but for now an expanded Marginal Risk is drawn.

...Mid-South through the Ohio Valley and Mid-Atlantic into New
England...

A strong cold front pushing south across the Midwest will run into
plentiful tropical moisture being drawn north from Tropical
Depression 2 in the Gulf. The front will act as a catalyst for
numerous segments of mostly fast moving thunderstorms across the
Ohio Valley and Interior Northeast through the Mid-Atlantic on
Tuesday, likely holding together for the into New England Tuesday
evening. PW of 2 to 2.25" ahead of the front and sufficient
instability will allow for heavy rainfall through this area,
possibly as far west as the Mid-South (per the RRFS and the 12Z
HRRR) and as far east as the New England coast up through Down East
Maine. Mean layer Wly to SWly flow of 40-50kt will keep activity
moving, but the threat for backbuilding and training storms as well
as the book ends of any segments could cause widely scattered
instances of flash flooding. The Slight Risk was expanded per 12Z
(and 18Z HRRR) CAM consensus along with chats with WFO PHI/OKX
through the northern Mid-Atlantic into Connecticut.

...Gulf Coast...

Tropical Depression 2 is still forecast to gradually drift west
with the center offshore until reaching southern Louisiana early
Thursday. Northerly shear and dry air entrainment will continue to
focus most associated precip south of the center with the banding
seen today east and north of the track over FL diminishing tonight
and having less coverage for Tuesday. This is in spite of this
being a tropical cyclone with PWATs up to 2.5 inches. Therefore,
the Marginal Risk for the Florida Panhandle through southeast
Louisiana remains in place with few changes.

Jackson/Wegman

Day 3
Valid 12Z Wed Jul 22 2026 - 12Z Thu Jul 23 2026

...THERE ARE SLIGHT RISKS OF EXCESSIVE RAINFALL FOR THE SOUTHERN
MID-ATLANTIC TO THE SOUTHERN APPALACHIANS, MUCH OF THE CENTRAL
ROCKIES, AND LOWER SOUTHEAST LOUISIANA...

...Mid-Atlantic to Tennessee Valley...

The cold front that reaches much of the Mid-Atlantic on Tuesday
will stall over the Delmarva through southern Virginia and the
southern Appalachians on Wednesday. Abundant Gulf moisture will
continue streaming northeastward from Tropical Depression 2 ahead
of the front with PW spiking above 2.25". Westerly mean layer flow
becomes parallel to this front on Wednesday which will promote
training activity and repeating heavy thunderstorms. This places
the focus farther north than the prior forecast with areas from the
Delmarva through North Carolina at risk where the Slight Risk was
redrawn. There remains a more "enhanced" Slight Risk over southeast
VA (including Hampton Roads) down toward Raleigh. The Slight Risk
was trimmed on the south end including over southern NC and most of
SC.

Since much of this area should get a break in heavy rain on Day 2,
a Moderate Risk was not considered at this time. However, this
stalled front will only slowly move south Wednesday to Friday which
may open the door to a Moderate Risk at some point over the
southern Mid-Atlantic/Carolinas.

...Central Gulf Coast...

Tropical Depression 2 is forecast to be drifting west toward the
mouth of the Mississippi on Wednesday. Northerly shear will
remain a concern to development of precip on the north side,
keeping most of the heaviest rains over the Gulf. The 12Z consensus
for heavy rain is even farther south than the previous forecast,
well south of New Orleans in an area that is not flash flood prone.
Out of an abundance of caution (a wise approach with tropical
systems) and in coordination with WFO LIX, the Slight Risk remains
in effect for lower southeast Louisiana. Some banding east and
north of the low center looks to track into the central Gulf Coast
where the Marginal Risk was expanded a bit.

...Intermountain West onto the Central Plains...

The shortwave trough tracking north from AZ on Wednesday should
focus the heaviest rain ahead of it over UT/CO up through WY and
eastern ID. The Slight Risk was expanded over these areas based on
the 12Z QPF consensus and in coordination with WFO BOU. Much of the
Rockies terrain is covered by a Slight Risk.

High pressure centered over MN brings some return flow across
Nebraska which warrants continuing the Marginal Risk there with an
expansion into northeast KS per the 12Z consensus.

The PW anomaly drops below 3 standard deviations for the Sierra
Nevada, but enough moisture remains to warrant another Marginal
Risk.

Jackson

Day 4 and Day 5

Valid 12Z Thu Jul 23 2026 - 12Z Sat Jul 25 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
CENTRAL PLAINS TO LOWER MISSOURI VALLEY, THE CENTRAL TO WESTERN
GULF COAST, AND THE EASTERN CAROLINAS ON DAY 4...

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
LOWER MISSOURI AND MID MISSISSIPPI VALLEYS, AND THE EASTERN
CAROLINAS ON DAY 5...

2030Z Update...
Removed the Slight Risk area from the Texas portion of the Day 4
Excessive Rainfall Outlook based on the forecast soundings along
and near the path of the system making its way along the Gulf coast
in the shorter periods. Based on NHC guidance available on Monday afternoon...the system should have transitioned to an extra-
tropical system by then which would facilitate the advection of unsaturated/drier air from the land.

Elsewhere changes tended to be pretty modest and still largely fit
the previous discussion.

Bann

Previous Discussion...

...Southeast...
A moisture-laden front will continue to sink slowly south across
the region. While the overnight guidance continues to present
differences on the timing of the front and corresponding
precipitation, there remains a strong signal for additional heavy
amounts impacting parts of the region, especially for portions of
the Carolinas. Precipitable Water values remaining around 2.25
inches along with periods of enhanced ascent will raise the threat
for additional heavy amounts most likely centered over eastern
North Carolina into northeast South Carolina Thursday into early
Friday. Due in part to model differences and forecast uncertainty,
maintained a Slight Risk. However, this has the potential to be a
second day in-a-row, and the fourth day this week for heavy rains
impacting parts of the region. Therefore, if forecast confidence
increases and the signal for a multi-day heavy rainfall event
holds, future upgrades may be required.

For Friday into early Saturday, it remains a question
whether the front will continue to push south, bringing drier
conditions into the Carolinas as the GFS/UKMET indicate, or
continue to hang up well to the north as shown by the ECMWF and
Canadian. Opted for a Slight Risk on for the Day 5, centered
similar to the Day 4 area, which presents a compromise between the
two camps and lined up with the higher probabilities from the most
recent ECENS.

...Gulf Coast...
Shear across Tropical Depression Two is expected to keep the
heaviest rainfall amounts associated with the system mostly south
of the center and offshore. However, cannot rule out the threat for
onshore flow supporting some locally heavy amounts along the coast,
especially if the trends support a stronger system and more
northerly track. Therefore, the a Slight Risk was maintained along
the Louisiana to the upper Texas Coast on Day 4.

A Marginal Risk was drawn for Day 5 from the upper Texas Coast
inland toward south-central Texas, where heavy amounts are
possible if the storm remains organized and continues to track
west.

...Central Plains to the Mid Mississippi Valley...
Models continue to show a well-defined shortwave sliding southeast
off of the top of the western U.S. ridge through the northern
Plains and into the mid Mississippi Valley on Day 4. Organized
heavy rain may develop late Thursday into early Friday as this
energy interacts with a deepening moisture pool fed by a
strengthening southwesterly jet. A Slight Risk was maintained on
Day 4 over parts of southeastern Nebraska into adjacent parts of
Kansas, Iowa, and Missouri, where models indicate the deepest
moisture, better forcing and greater potential for localized
training will center. Storms continuing through Friday morning and
possibly redeveloping later in the day downstream will extend the
threat across across a greater part of the mid Mississippi Valley
on Day 5.

...Southwest/Great Basin/Central and Southern Rockies...
Monsoon moisture will continue to fuel diurnal activity, however
the footprint is expected to diminish especially by Day 5 as
moisture anomalies drop off and heights build across the Southwest.

Pereira

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!5xkd0pG2dOAZa8lWxyBvO31EXn82D9V-YuQI1YujG9a4puPuD6CaUcmSPTJhE622P7r9dcTz0cfFPBx_sXxdACUClQc$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!5xkd0pG2dOAZa8lWxyBvO31EXn82D9V-YuQI1YujG9a4puPuD6CaUcmSPTJhE622P7r9dcTz0cfFPBx_sXxdhf81fnw$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!5xkd0pG2dOAZa8lWxyBvO31EXn82D9V-YuQI1YujG9a4puPuD6CaUcmSPTJhE622P7r9dcTz0cfFPBx_sXxdMoAxMGw$

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Jul 21 00:55:46 2026

FOUS30 KWBC 210055
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
855 PM EDT Mon Jul 20 2026

Day 1
Valid 01Z Tue Jul 21 2026 - 12Z Tue Jul 21 2026

...THERE ARE SLIGHT RISKS OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHWEST AND NORTH CAROLINA...

...Southwest...

01Z Update...little change needed as monsoon moisture continues to
stream across the Southwest into the Great Basin with renewed
diurnal convective coverage. Elevated moisture with PW of 2 to 2.5
standard deviations above normal and limited cloud cover earlier
today allowed for good coverage of convection. Focus of heavies
along the Mogollon Rim, southeast Arizona and southern New Mexico.

...Southern Mid-Atlantic to southern Appalachians...

A warm front on leaving edge of deep tropical moisture plume
extending northeastward from Tropical Storm Bertha in the Gulf.
The front will continue to provide enough forcing across much of
eastern North Carolina to allow for convection to persist into the
late evening/early morning hours. Soils have moistened somewhat but
should still be able to handle additional rainfall without too many
problems. Above normal moisture for the storms to work and the
front providing some forcing warrants continuation of the Slight
Risk.

...Gulf Coast...

The outermost periphery of circulation around Tropical Storm
Bertha continued to impact the Gulf Coast of Florida, through the
Panhandle into southern Georgia, and over to southeastern
Louisiana this evening. Banding is occurring, so there are
localized instances of multiple inch per hour rainfall rates.
Regardless, the center remains far enough offshore, with satellite
imagery from this evening still showing drier air aloft working to significantly cut down on the overall coverage of storms.
Considering the dry soils and high FFGs typical of the immediate
Gulf Coast, even periods of heavy rain should only result in
isolated instances of flash flooding. Thus, there was little change
to the Marginal Risk area.

...Midwest...

The Marginal Risk across much of the Midwest and upper Great Lakes
also remains largely intact with the outlook area updated based on
trends of late afternoon/early evening satellite imagery. progression
It appears the most likely areas to be impacted tonight are from
central Iowa east across northern Illinois. Dry soils highlight
this area, so this being the height of the growing season should
mitigate the flash flood risk.

Jackson/Bann

Day 2
Valid 12Z Tue Jul 21 2026 - 12Z Wed Jul 22 2026

...THERE ARE SLIGHT RISKS OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE SOUTHWEST AND THE MID-ATLANTIC TO THE OHIO VALLEY...

...Intermountain West...

Monsoonal moisture continues to arrive over the Southwest from the
sub-tropical Pacific around a mid-level high centered over
Colorado. A shortwave trough will track from southwest NM into
eastern AZ which will promote increased convective coverage over
both AZ and UT into NV. The Slight Risk area was further expanded
to include most of UT through central NV. The greatest convective
coverage and most impactful flash flooding is still expected from
southeast AZ up through the Mogollon Rim to the Grand Canyon which
is considered a more "enhanced" Slight Risk. A fair amount of
convective coverage tonight over AZ may cause some opaque stratus
to persist into Tuesday which could at least locally disrupt the
diurnal trend in activity.

The PW anomaly reaches 4 standard deviations above normal over the
Sierra Nevada on Tuesday. This should promote vigorous diurnal
convection up the High Sierra to Lake Tahoe. A Slight Risk may be
warranted, but for now an expanded Marginal Risk is drawn.

...Mid-South through the Ohio Valley and Mid-Atlantic into New
England...

A strong cold front pushing south across the Midwest will run into
plentiful tropical moisture being drawn north from Tropical
Depression 2 in the Gulf. The front will act as a catalyst for
numerous segments of mostly fast moving thunderstorms across the
Ohio Valley and Interior Northeast through the Mid-Atlantic on
Tuesday, likely holding together for the into New England Tuesday
evening. PW of 2 to 2.25" ahead of the front and sufficient
instability will allow for heavy rainfall through this area,
possibly as far west as the Mid-South (per the RRFS and the 12Z
HRRR) and as far east as the New England coast up through Down East
Maine. Mean layer Wly to SWly flow of 40-50kt will keep activity
moving, but the threat for backbuilding and training storms as well
as the book ends of any segments could cause widely scattered
instances of flash flooding. The Slight Risk was expanded per 12Z
(and 18Z HRRR) CAM consensus along with chats with WFO PHI/OKX
through the northern Mid-Atlantic into Connecticut.

...Gulf Coast...

Tropical Depression 2 is still forecast to gradually drift west
with the center offshore until reaching southern Louisiana early
Thursday. Northerly shear and dry air entrainment will continue to
focus most associated precip south of the center with the banding
seen today east and north of the track over FL diminishing tonight
and having less coverage for Tuesday. This is in spite of this
being a tropical cyclone with PWATs up to 2.5 inches. Therefore,
the Marginal Risk for the Florida Panhandle through southeast
Louisiana remains in place with few changes.

Jackson/Wegman

Day 3
Valid 12Z Wed Jul 22 2026 - 12Z Thu Jul 23 2026

...THERE ARE SLIGHT RISKS OF EXCESSIVE RAINFALL FOR THE SOUTHERN
MID-ATLANTIC TO THE SOUTHERN APPALACHIANS, MUCH OF THE CENTRAL
ROCKIES, AND LOWER SOUTHEAST LOUISIANA...

...Mid-Atlantic to Tennessee Valley...

The cold front that reaches much of the Mid-Atlantic on Tuesday
will stall over the Delmarva through southern Virginia and the
southern Appalachians on Wednesday. Abundant Gulf moisture will
continue streaming northeastward from Tropical Depression 2 ahead
of the front with PW spiking above 2.25". Westerly mean layer flow
becomes parallel to this front on Wednesday which will promote
training activity and repeating heavy thunderstorms. This places
the focus farther north than the prior forecast with areas from the
Delmarva through North Carolina at risk where the Slight Risk was
redrawn. There remains a more "enhanced" Slight Risk over southeast
VA (including Hampton Roads) down toward Raleigh. The Slight Risk
was trimmed on the south end including over southern NC and most of
SC.

Since much of this area should get a break in heavy rain on Day 2,
a Moderate Risk was not considered at this time. However, this
stalled front will only slowly move south Wednesday to Friday which
may open the door to a Moderate Risk at some point over the
southern Mid-Atlantic/Carolinas.

...Central Gulf Coast...

Tropical Depression 2 is forecast to be drifting west toward the
mouth of the Mississippi on Wednesday. Northerly shear will
remain a concern to development of precip on the north side,
keeping most of the heaviest rains over the Gulf. The 12Z consensus
for heavy rain is even farther south than the previous forecast,
well south of New Orleans in an area that is not flash flood prone.
Out of an abundance of caution (a wise approach with tropical
systems) and in coordination with WFO LIX, the Slight Risk remains
in effect for lower southeast Louisiana. Some banding east and
north of the low center looks to track into the central Gulf Coast
where the Marginal Risk was expanded a bit.

...Intermountain West onto the Central Plains...

The shortwave trough tracking north from AZ on Wednesday should
focus the heaviest rain ahead of it over UT/CO up through WY and
eastern ID. The Slight Risk was expanded over these areas based on
the 12Z QPF consensus and in coordination with WFO BOU. Much of the
Rockies terrain is covered by a Slight Risk.

High pressure centered over MN brings some return flow across
Nebraska which warrants continuing the Marginal Risk there with an
expansion into northeast KS per the 12Z consensus.

The PW anomaly drops below 3 standard deviations for the Sierra
Nevada, but enough moisture remains to warrant another Marginal
Risk.

Jackson

Day 4 and Day 5

Valid 12Z Thu Jul 23 2026 - 12Z Sat Jul 25 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
CENTRAL PLAINS TO LOWER MISSOURI VALLEY, THE CENTRAL TO WESTERN
GULF COAST, AND THE EASTERN CAROLINAS ON DAY 4...

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
LOWER MISSOURI AND MID MISSISSIPPI VALLEYS, AND THE EASTERN
CAROLINAS ON DAY 5...

2030Z Update...
Removed the Slight Risk area from the Texas portion of the Day 4
Excessive Rainfall Outlook based on the forecast soundings along
and near the path of the system making its way along the Gulf coast
in the shorter periods. Based on NHC guidance available on Monday afternoon...the system should have transitioned to an extra-
tropical system by then which would facilitate the advection of unsaturated/drier air from the land.

Elsewhere changes tended to be pretty modest and still largely fit
the previous discussion.

Bann

Previous Discussion...

...Southeast...
A moisture-laden front will continue to sink slowly south across
the region. While the overnight guidance continues to present
differences on the timing of the front and corresponding
precipitation, there remains a strong signal for additional heavy
amounts impacting parts of the region, especially for portions of
the Carolinas. Precipitable Water values remaining around 2.25
inches along with periods of enhanced ascent will raise the threat
for additional heavy amounts most likely centered over eastern
North Carolina into northeast South Carolina Thursday into early
Friday. Due in part to model differences and forecast uncertainty,
maintained a Slight Risk. However, this has the potential to be a
second day in-a-row, and the fourth day this week for heavy rains
impacting parts of the region. Therefore, if forecast confidence
increases and the signal for a multi-day heavy rainfall event
holds, future upgrades may be required.

For Friday into early Saturday, it remains a question
whether the front will continue to push south, bringing drier
conditions into the Carolinas as the GFS/UKMET indicate, or
continue to hang up well to the north as shown by the ECMWF and
Canadian. Opted for a Slight Risk on for the Day 5, centered
similar to the Day 4 area, which presents a compromise between the
two camps and lined up with the higher probabilities from the most
recent ECENS.

...Gulf Coast...
Shear across Tropical Depression Two is expected to keep the
heaviest rainfall amounts associated with the system mostly south
of the center and offshore. However, cannot rule out the threat for
onshore flow supporting some locally heavy amounts along the coast,
especially if the trends support a stronger system and more
northerly track. Therefore, the a Slight Risk was maintained along
the Louisiana to the upper Texas Coast on Day 4.

A Marginal Risk was drawn for Day 5 from the upper Texas Coast
inland toward south-central Texas, where heavy amounts are
possible if the storm remains organized and continues to track
west.

...Central Plains to the Mid Mississippi Valley...
Models continue to show a well-defined shortwave sliding southeast
off of the top of the western U.S. ridge through the northern
Plains and into the mid Mississippi Valley on Day 4. Organized
heavy rain may develop late Thursday into early Friday as this
energy interacts with a deepening moisture pool fed by a
strengthening southwesterly jet. A Slight Risk was maintained on
Day 4 over parts of southeastern Nebraska into adjacent parts of
Kansas, Iowa, and Missouri, where models indicate the deepest
moisture, better forcing and greater potential for localized
training will center. Storms continuing through Friday morning and
possibly redeveloping later in the day downstream will extend the
threat across across a greater part of the mid Mississippi Valley
on Day 5.

...Southwest/Great Basin/Central and Southern Rockies...
Monsoon moisture will continue to fuel diurnal activity, however
the footprint is expected to diminish especially by Day 5 as
moisture anomalies drop off and heights build across the Southwest.

Pereira

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!5Kz3l6kv1fug5sf5iKYbw27tnlmfo3gJwanpIg0lS9sg0Cyako0evZvBl5lBQ5cA1LLtoQkACecM36IXGmRKcs0zvt0$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!5Kz3l6kv1fug5sf5iKYbw27tnlmfo3gJwanpIg0lS9sg0Cyako0evZvBl5lBQ5cA1LLtoQkACecM36IXGmRKn1AzJG8$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!5Kz3l6kv1fug5sf5iKYbw27tnlmfo3gJwanpIg0lS9sg0Cyako0evZvBl5lBQ5cA1LLtoQkACecM36IXGmRK67UgHB8$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Jul 21 08:36:10 2026

FOUS30 KWBC 210835
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
435 AM EDT Tue Jul 21 2026

Day 1
Valid 12Z Tue Jul 21 2026 - 12Z Wed Jul 22 2026

...THERE ARE SLIGHT RISKS OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHWEST AND GREAT BASIN AS WELL AS FOR PORTIONS OF THE OHIO AND
TENNESSEE VALLEYS AND INTO THE NORTHEAST...

...Southwest and Great Basin...

The combination of anomalous monsoonal moisture streaming northward
out of the tropical Pacific and a retrograding upper level
shortwave will create a very active day for thunderstorm activity
this afternoon across much of the Pacific Northwest. Moisture
amounts will be anywhere from 2-4 sigma above normal, with PWATs
above 1.5 inches in southern Arizona, and above 1 inch across much
of the rest of the Southwest. The upper level disturbance tracking
west out of New Mexico will force numerous thunderstorms to form
across Arizona. The storms will slowly track westward. Greater
concentrations of storms are expected along the Mogollon Rim where
topography will help allow the storms to congeal along the Rim. Due
to the above normal amounts of moisture, the storms will be capable
of heavy rainfall with the strongest cores possibly producing
rainfall rates to 2 inches per hour. Given the very favorable
hydrology of the Desert Southwest for flash flooding, given
generally very hydrophobic soils and bare rocks, the Slight Risk
remains in place across much of Arizona, with a higher-end Slight
stretching from the southeast corner of the state northwestward
along the Rim to the Grand Canyon. As usual, slot canyons, dry
washes, and other low-lying areas will be more susceptible to
impactful flash flooding downstream of the heaviest rains.

Further north across the Great Basin, the area will be on the
western periphery of the large ridge over Colorado and a nearly
stationary longwave trough off the coast of northern California. A
separate shortwave trough will track across Nevada and into Idaho
this afternoon. Given similarly anomalous amounts of atmospheric
moisture in place as well across this largely flash-flood prone
area from the Sierras east through Utah, clusters of storms will
form in this area associated with the upper level shortwave.

The inherited Slight was expanded west to include the Sierras,
where upslope will greatly contribute to afternoon and evening
thunderstorm activity there, while the steep slopes will support
fast-forming flash flooding downstream of any heavy rain producing thunderstorms. Elsewhere, few changes were needed, as many of the
areas in the Slight that will be impacted by storms again today
were impacted on previous days, worsening the flash flooding risk.

...Ohio and Tennessee Valleys into the Northeast...

Much of the flooding risk across the eastern half of the country
today will be in association with a strong cold front at the
leading edge of a strong longwave trough over the Great Lakes
pushing south and east across the Ohio and Tennessee Valleys as
well as into the Northeast. Anomalous moisture originating in part
from T.S. Bertha in the Gulf will ride northeastward ahead of the
front, providing plentiful moisture for numerous thunderstorms to
form, some of which will produce multiple-inch-per-hour rainfall
rates. A few areas within the broader Slight Risk are likely to
see more rainfall. In central Kentucky and central Tennessee, a southwest-to-northeast oriented band of storms is expected to form
on the leading edge of the cold front, with mesoscale "slow-downs"
in the front's progression allowing for a second round of activity
possibly forming over these same areas where FFGs are depressed
from heavy rainfall in recent days.

The greatest rainfall totals are expected to be across portions of
southeastern Virginia, generally from the Richmond metro east
across the Bay and impacting the lower Maryland and Virginia
sections of the Delmarva. Here, a plume of greater moisture will
interact with the front which will be slowed by its passage across
the mountains. An early to mid afternoon round of storms with the
initial approach of the upper level trough and associated shortwave
energy will move across southern Virginia first. Much more numerous
storms will impact the area in the evening hours as the main front
approaches the area. Despite the loss of daytime heating, the front
is expected to stall over southern Virginia, which could very well
allow for a prolonged period of training storms to set up in the
aforementioned area, which will persist through the overnight. A
short-fused Moderate Risk cannot be ruled out should this evolution
play out as expected by several of the CAMs.

Finally, across the area form northern New Jersey northeast into
the Hudson Valley, morning thunderstorms caught along the Catskills
and Poconos associated with a warm front may start out the day with
a period of training thunderstorms as moisture and instability
levels increase south of the front. This will likely be the feature
that causes the most rainfall in the area. Once the fast-moving
cold front sweeps eastward across the area, resulting in a much
shorter period of widespread thunderstorm activity, its passage
will end the threat for heavy rain in this area for the night.

...Gulf Coast/Tropical Storm Bertha...

As has been the case for several days, the convective pattern with
Bertha in the guidance is little changed. Northeasterly shear will
continue to keep any persistent heavy rainfall well south of the
Gulf Coast for the next several days. Only small and isolated bands
of rain trying to wrap around the center will impact the coast.
The inherited Marginal Risk remains little changed from Louisiana
through the Florida Panhandle.

Wegman

Day 2
Valid 12Z Wed Jul 22 2026 - 12Z Thu Jul 23 2026

...THERE ARE SLIGHT RISKS FOR EXCESSIVE RAINFALL OVER PORTIONS OF
THE INTERMOUNTAIN WEST AS WELL AS FROM NORTHERN GEORGIA THROUGH THE
TIDEWATER OF VIRGINIA AND NORTH CAROLINA...

...Intermountain West...

Highly anomalous amounts of atmospheric moisture associated with
the monsoon over the Intermountain West will be activated by rapid
height falls as an upper level and highly negatively tilted trough
pushes east from off the coast of Washington and Oregon. Meanwhile,
separate upper level energy undercutting the ridge will also
provide additional forcing further east across eastern Idaho and
Wyoming. Once again, numerous thunderstorms will form in the
anomalous moisture and for many areas, will be tied to the local
topography. Few changes were needed with this update. The greatest
amounts of rain look to concentrate in western Wyoming, where any
storms south of Yellowstone could necessitate a higher-end Slight
for some of those areas, as well as for the Uintas of northern
Utah. With nearly all of the forcing further north, the Marginal
Risk into southern Arizona and southern New Mexico was trimmed
significantly with this update, as ridging quickly overtakes this
area and limits convective potential south/west of the Mogollon Rim
as a result.

...Carolinas, Southern Virginia, and Northern Georgia...

A strong cold front running into highly anomalous moisture being
siphoned from the circulation of Tropical Storm Bertha will
exacerbate the gradient of moisture along the frontal interface
through the day across the Carolinas and into southeastern
Virginia. This will work to keep any forward progress of the front
minimal. Storms will train along the front, especially across
northeastern North Carolina and into southeastern Virginia. This
area remains in a higher-end Slight Risk and with the stalled out
front remaining to guide the frequent development of additional
storms, a Moderate Risk upgrade in areas where the storms focused
in the Day 1 period remains a distinct possibility. Guidance has
been laser focused in this area and so forecast changes have been
minimal. Further south and west, however, guidance has become
increasingly optimistic on storms developing further west into the
southern Appalachians. As such, the Slight Risk was expanded west
to include this region from north of Atlanta through the western
Carolinas.

...Tropical Storm Bertha/Gulf Coast...

Strengthening shear across the circulation will continue to keep
any organized convection and meaningful rainfall out over the open
waters of the Gulf. The immediate coastline could still see amounts
greater than an inch, but the rainfall footprint continues to shift
off the coast. In coordination with LIX/Slidell, LA forecast
office, the inherited Slight Risk for this region was downgraded
with this update, with the overall area of the surrounding Marginal
remaining little changed. What little rainfall does impact land
areas remains with the potential to be locally heavy, so
unfortunately no changes to the Marginal Risks can be made so long
as Bertha remains a tropical entity.

Wegman

Day 3
Valid 12Z Thu Jul 23 2026 - 12Z Fri Jul 24 2026

...THERE ARE SLIGHT RISKS FOR EXCESSIVE RAINFALL FOR A PORTION OF
THE SOUTHEAST FROM GEORGIA THROUGH THE CAROLINAS AS WELL AS FOR
NORTHEAST KANSAS AND SOUTHEAST NEBRASKA...

...Southeast...

The stalled out front that has remained across the Southeast will
continue to plague the area with very heavy rainfall, as the
continuous stream of Gulf moisture from the Gulf funnels
northeastward along the front. Yet another day of heavy rain is
expected to impact the Carolinas as a result. The front may drift
ever so slightly further south and east which should clear all but
the Hampton Roads area of far southeast Virginia from the heavy
rainfall threat by Thursday, but for much of eastern North
Carolina, much of South Carolina, and portions of northern Georgia,
generally from Atlanta east, the heavy rainfall threat will
continue through Thursday. Once again, potential for very heavy
rainfall totals in many areas as are expected to see heavy rain
from Wednesday could mean further upgrades to the risks may be
needed, especially across eastern North Carolina. Ultimately, where
the heaviest rain falls both today and Wednesday should dictate if
further upgrades will be needed.

...Central Plains...

An MCS is expected to impact a portion of northeast Kansas,
southeast Nebraska and the Kansas City and St. Joseph metros on
Thursday. The heavy rainfall footprint has drifted south and west,
so the Slight Risk has been adjusted accordingly. As with many
MCS's the location of the heaviest rain is likely to continue
shifting with future updates, most likely towards the south, so
stay tuned for further updates. Periods of heavy rain may continue
to impact Wyoming into Colorado as well, where upgrades to a Slight
are also probable, depending on where the heavy rains from
Wednesday overlap with Thursday's forecast.

...Bertha...

Bertha, who may no longer be a tropical cyclone by Thursday, and
likely to be in a weakening state, should continue to keep any
associated rainfall off the coast. The immediate coast remains with
the best chance for seeing anything over an inch of associated
rainfall. FFGs are significantly higher than that in all areas.
Given this, and with very good consistency in this scenario in the
guidance, the inherited Slight and Marginal for a portion of the
Texas and Louisiana Gulf coasts was removed with this update. The
Marginal Risk has been downgraded to under a 5% risk for the upper
Texas Gulf Coast, as well as the Slight for coastal Louisiana
downgraded to a Marginal with this update.

Wegman

Day 4 and Day 5

Valid 12Z Fri Jul 24 2026 - 12Z Sun Jul 26 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
LOWER MISSOURI VALLEY AND MID MISSISSIPPI VALLEYS ON DAY 4 AND FOR
PARTS OF SOUTHEAST COAST DAYS 4 AND 5...

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
LOWER MISSOURI AND MID MISSISSIPPI VALLEYS, AND THE EASTERN
CAROLINAS ON DAY 5...

...Southeast...
A multi-day rainfall event is expected to continue into the
weekend, with additional heavy rains likely, especially for parts
of southeastern Virginia and the Carolinas. The focus for these
rains will be a slow-moving, moisture-laden front that is forecast
to linger across the region through at least the first half of the
weekend. Southwesterly flow ahead of a shortwave trough moving
through the Ohio/Tennessee valleys will further fortify the already moisture-rich airmass, with models showing PWs increasing in
excess of 2.25 inches (+2 to 3 sigma). This moisture, along with
pockets of enhanced ascent afforded by mid-level energy, will
support periods of heavy, highly-efficient rainfall. While areas of
heavy rainfall are likely, forecast confidence regarding their
placement remains limited due to continuing model spread with
regards to the placement of the front, which will have impacts on
where the heaviest amounts occur.

...Gulf Coast...
Northeasterly shear and dry air north of the center should keep
much of the heavy rainfall threat associated with T.S. Bertha out
over the open waters. Also, there is some question regarding the
intensity of the system and if it will retain a closed circulation
as it moves from the Louisiana onto the upper Texas coasts early in
the period. However, cannot not rule out an isolated threat for
heavy rainfall and therefore maintained a Marginal Risk for now
from the southwestern Louisiana to the upper Texas coasts on Day 4.

...Lower Missouri-Mid Mississippi to the Tennessee Valleys/Southern Appalachians...
Ongoing storms associated with pooling moisture along a low-level
boundary and ahead a mid-level shortwave dropping southeast may
continue to support storms and the threat for heavy rains Friday
morning (Day 4) across parts of the lower Missouri Valley. Storms
are expected to wane by late in the morning, but there remains a
model signal for new storms developing farther to the south and
east as additional energy interacts with deepening moisture (PWs
increasing to 2-2.25 inches) that will be supported by
southwesterly low level inflow.

As this energy spills farther south, it may help to organize heavy
rainfall across portions of the Tennessee Valley into the southern Appalachians, where a Marginal Risk was introduced for Day 5.
Forecast confidence was limited by model spread, however this may
be an area where a targeted upgrade is required in a future update
if confidence increases.

...Southwest/Great Basin/Central and Southern Rockies...
After what is expected to be a downward trend in convective
coverage and potential flash flooding late in the week (Day 4),
moisture anomalies are forecast to increase again on Saturday. This
increasing moisture along with mid level energy moving around the
southwestern periphery of a broad high will help expand afternoon
and evening storm coverage, including the southern Arizona deserts.

Pereira

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!_7f5Jd884SzvAK0pvfHKJYaCJx5ZvY5nW3xiWxOPgG7XujEBfoZKZwOBsL5JvUiymC4eCPNFhTD-URhfs8a5ilfqXAc$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!_7f5Jd884SzvAK0pvfHKJYaCJx5ZvY5nW3xiWxOPgG7XujEBfoZKZwOBsL5JvUiymC4eCPNFhTD-URhfs8a51kKcAnQ$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!_7f5Jd884SzvAK0pvfHKJYaCJx5ZvY5nW3xiWxOPgG7XujEBfoZKZwOBsL5JvUiymC4eCPNFhTD-URhfs8a5ywQoYx8$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Jul 21 08:48:14 2026

FOUS30 KWBC 210847
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
447 AM EDT Tue Jul 21 2026

Day 1
Valid 12Z Tue Jul 21 2026 - 12Z Wed Jul 22 2026

...THERE ARE SLIGHT RISKS OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHWEST AND GREAT BASIN AS WELL AS FOR PORTIONS OF THE OHIO AND
TENNESSEE VALLEYS AND INTO THE NORTHEAST...

...Southwest and Great Basin...

The combination of anomalous monsoonal moisture streaming northward
out of the tropical Pacific and a retrograding upper level
shortwave will create a very active day for thunderstorm activity
this afternoon across much of the Pacific Northwest. Moisture
amounts will be anywhere from 2-4 sigma above normal, with PWATs
above 1.5 inches in southern Arizona, and above 1 inch across much
of the rest of the Southwest. The upper level disturbance tracking
west out of New Mexico will force numerous thunderstorms to form
across Arizona. The storms will slowly track westward. Greater
concentrations of storms are expected along the Mogollon Rim where
topography will help allow the storms to congeal along the Rim. Due
to the above normal amounts of moisture, the storms will be capable
of heavy rainfall with the strongest cores possibly producing
rainfall rates to 2 inches per hour. Given the very favorable
hydrology of the Desert Southwest for flash flooding, given
generally very hydrophobic soils and bare rocks, the Slight Risk
remains in place across much of Arizona, with a higher-end Slight
stretching from the southeast corner of the state northwestward
along the Rim to the Grand Canyon. As usual, slot canyons, dry
washes, and other low-lying areas will be more susceptible to
impactful flash flooding downstream of the heaviest rains.

Further north across the Great Basin, the area will be on the
western periphery of the large ridge over Colorado and a nearly
stationary longwave trough off the coast of northern California. A
separate shortwave trough will track across Nevada and into Idaho
this afternoon. Given similarly anomalous amounts of atmospheric
moisture in place as well across this largely flash-flood prone
area from the Sierras east through Utah, clusters of storms will
form in this area associated with the upper level shortwave.

The inherited Slight was expanded west to include the Sierras,
where upslope will greatly contribute to afternoon and evening
thunderstorm activity there, while the steep slopes will support
fast-forming flash flooding downstream of any heavy rain producing thunderstorms. Elsewhere, few changes were needed, as many of the
areas in the Slight that will be impacted by storms again today
were impacted on previous days, worsening the flash flooding risk.

...Ohio and Tennessee Valleys into the Northeast...

Much of the flooding risk across the eastern half of the country
today will be in association with a strong cold front at the
leading edge of a strong longwave trough over the Great Lakes
pushing south and east across the Ohio and Tennessee Valleys as
well as into the Northeast. Anomalous moisture originating in part
from T.S. Bertha in the Gulf will ride northeastward ahead of the
front, providing plentiful moisture for numerous thunderstorms to
form, some of which will produce multiple-inch-per-hour rainfall
rates. A few areas within the broader Slight Risk are likely to
see more rainfall. In central Kentucky and central Tennessee, a southwest-to-northeast oriented band of storms is expected to form
on the leading edge of the cold front, with mesoscale "slow-downs"
in the front's progression allowing for a second round of activity
possibly forming over these same areas where FFGs are depressed
from heavy rainfall in recent days.

The greatest rainfall totals are expected to be across portions of
southeastern Virginia, generally from the Richmond metro east
across the Bay and impacting the lower Maryland and Virginia
sections of the Delmarva. Here, a plume of greater moisture will
interact with the front which will be slowed by its passage across
the mountains. An early to mid afternoon round of storms with the
initial approach of the upper level trough and associated shortwave
energy will move across southern Virginia first. Much more numerous
storms will impact the area in the evening hours as the main front
approaches the area. Despite the loss of daytime heating, the front
is expected to stall over southern Virginia, which could very well
allow for a prolonged period of training storms to set up in the
aforementioned area, which will persist through the overnight. A
short-fused Moderate Risk cannot be ruled out should this evolution
play out as expected by several of the CAMs.

Finally, across the area form northern New Jersey northeast into
the Hudson Valley, morning thunderstorms caught along the Catskills
and Poconos associated with a warm front may start out the day with
a period of training thunderstorms as moisture and instability
levels increase south of the front. This will likely be the feature
that causes the most rainfall in the area. Once the fast-moving
cold front sweeps eastward across the area, resulting in a much
shorter period of widespread thunderstorm activity, its passage
will end the threat for heavy rain in this area for the night.

...Gulf Coast/Tropical Storm Bertha...

As has been the case for several days, the convective pattern with
Bertha in the guidance is little changed. Northeasterly shear will
continue to keep any persistent heavy rainfall well south of the
Gulf Coast for the next several days. Only small and isolated bands
of rain trying to wrap around the center will impact the coast.
The inherited Marginal Risk remains little changed from Louisiana
through the Florida Panhandle.

Wegman

Day 2
Valid 12Z Wed Jul 22 2026 - 12Z Thu Jul 23 2026

...THERE ARE SLIGHT RISKS FOR EXCESSIVE RAINFALL OVER PORTIONS OF
THE INTERMOUNTAIN WEST AS WELL AS FROM NORTHERN GEORGIA THROUGH THE
TIDEWATER OF VIRGINIA AND NORTH CAROLINA...

...Intermountain West...

Highly anomalous amounts of atmospheric moisture associated with
the monsoon over the Intermountain West will be activated by rapid
height falls as an upper level and highly negatively tilted trough
pushes east from off the coast of Washington and Oregon. Meanwhile,
separate upper level energy undercutting the ridge will also
provide additional forcing further east across eastern Idaho and
Wyoming. Once again, numerous thunderstorms will form in the
anomalous moisture and for many areas, will be tied to the local
topography. Few changes were needed with this update. The greatest
amounts of rain look to concentrate in western Wyoming, where any
storms south of Yellowstone could necessitate a higher-end Slight
for some of those areas, as well as for the Uintas of northern
Utah. With nearly all of the forcing further north, the Marginal
Risk into southern Arizona and southern New Mexico was trimmed
significantly with this update, as ridging quickly overtakes this
area and limits convective potential south/west of the Mogollon Rim
as a result.

...Carolinas, Southern Virginia, and Northern Georgia...

A strong cold front running into highly anomalous moisture being
siphoned from the circulation of Tropical Storm Bertha will
exacerbate the gradient of moisture along the frontal interface
through the day across the Carolinas and into southeastern
Virginia. This will work to keep any forward progress of the front
minimal. Storms will train along the front, especially across
northeastern North Carolina and into southeastern Virginia. This
area remains in a higher-end Slight Risk and with the stalled out
front remaining to guide the frequent development of additional
storms, a Moderate Risk upgrade in areas where the storms focused
in the Day 1 period remains a distinct possibility. Guidance has
been laser focused in this area and so forecast changes have been
minimal. Further south and west, however, guidance has become
increasingly optimistic on storms developing further west into the
southern Appalachians. As such, the Slight Risk was expanded west
to include this region from north of Atlanta through the western
Carolinas.

...Tropical Storm Bertha/Gulf Coast...

Strengthening shear across the circulation will continue to keep
any organized convection and meaningful rainfall out over the open
waters of the Gulf. The immediate coastline could still see amounts
greater than an inch, but the rainfall footprint continues to shift
off the coast. In coordination with LIX/Slidell, LA forecast
office, the inherited Slight Risk for this region was downgraded
with this update, with the overall area of the surrounding Marginal
remaining little changed. What little rainfall does impact land
areas remains with the potential to be locally heavy, so
unfortunately no changes to the Marginal Risks can be made so long
as Bertha remains a tropical entity.

Wegman

Day 3
Valid 12Z Thu Jul 23 2026 - 12Z Fri Jul 24 2026

...THERE ARE SLIGHT RISKS FOR EXCESSIVE RAINFALL FOR A PORTION OF
THE SOUTHEAST FROM GEORGIA THROUGH THE CAROLINAS AS WELL AS FOR
NORTHEAST KANSAS AND SOUTHEAST NEBRASKA...

...Southeast...

The stalled out front that has remained across the Southeast will
continue to plague the area with very heavy rainfall, as the
continuous stream of Gulf moisture from the Gulf funnels
northeastward along the front. Yet another day of heavy rain is
expected to impact the Carolinas as a result. The front may drift
ever so slightly further south and east which should clear all but
the Hampton Roads area of far southeast Virginia from the heavy
rainfall threat by Thursday, but for much of eastern North
Carolina, much of South Carolina, and portions of northern Georgia,
generally from Atlanta east, the heavy rainfall threat will
continue through Thursday. Once again, potential for very heavy
rainfall totals in many areas as are expected to see heavy rain
from Wednesday could mean further upgrades to the risks may be
needed, especially across eastern North Carolina. Ultimately, where
the heaviest rain falls both today and Wednesday should dictate if
further upgrades will be needed.

...Central Plains...

An MCS is expected to impact a portion of northeast Kansas,
southeast Nebraska and the Kansas City and St. Joseph metros on
Thursday. The heavy rainfall footprint has drifted south and west,
so the Slight Risk has been adjusted accordingly. As with many
MCS's the location of the heaviest rain is likely to continue
shifting with future updates, most likely towards the south, so
stay tuned for further updates. Periods of heavy rain may continue
to impact Wyoming into Colorado as well, where upgrades to a Slight
are also probable, depending on where the heavy rains from
Wednesday overlap with Thursday's forecast.

...Bertha...

Bertha, who may no longer be a tropical cyclone by Thursday, and
likely to be in a weakening state, should continue to keep any
associated rainfall off the coast. The immediate coast remains with
the best chance for seeing anything over an inch of associated
rainfall. FFGs are significantly higher than that in all areas.
Given this, and with very good consistency in this scenario in the
guidance, the inherited Slight and Marginal for a portion of the
Texas and Louisiana Gulf coasts was removed with this update. The
Marginal Risk has been downgraded to under a 5% risk for the upper
Texas Gulf Coast, as well as the Slight for coastal Louisiana
downgraded to a Marginal with this update.

Wegman

Day 4 and Day 5

Valid 12Z Fri Jul 24 2026 - 12Z Sun Jul 26 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
LOWER MISSOURI VALLEY AND MID MISSISSIPPI VALLEYS ON DAY 4 AND FOR
PARTS OF SOUTHEAST COAST DAYS 4 AND 5...

...Southeast...
A multi-day rainfall event is expected to continue into the
weekend, with additional heavy rains likely, especially for parts
of southeastern Virginia and the Carolinas. The focus for these
rains will be a slow-moving, moisture-laden front that is forecast
to linger across the region through at least the first half of the
weekend. Southwesterly flow ahead of a shortwave trough moving
through the Ohio/Tennessee valleys will further fortify the already moisture-rich airmass, with models showing PWs increasing in
excess of 2.25 inches (+2 to 3 sigma). This moisture, along with
pockets of enhanced ascent afforded by mid-level energy, will
support periods of heavy, highly-efficient rainfall. While areas of
heavy rainfall are likely, forecast confidence regarding their
placement remains limited due to continuing model spread with
regards to the placement of the front, which will have impacts on
where the heaviest amounts occur.

...Gulf Coast...
Northeasterly shear and dry air north of the center should keep
much of the heavy rainfall threat associated with T.S. Bertha out
over the open waters. Also, there is some question regarding the
intensity of the system and if it will retain a closed circulation
as it moves from the Louisiana onto the upper Texas coasts early in
the period. However, cannot not rule out an isolated threat for
heavy rainfall and therefore maintained a Marginal Risk for now
from the southwestern Louisiana to the upper Texas coasts on Day 4.

...Lower Missouri-Mid Mississippi to the Tennessee Valleys/Southern Appalachians...
Ongoing storms associated with pooling moisture along a low-level
boundary and ahead a mid-level shortwave dropping southeast may
continue to support storms and the threat for heavy rains Friday
morning (Day 4) across parts of the lower Missouri Valley. Storms
are expected to wane by late in the morning, but there remains a
model signal for new storms developing farther to the south and
east as additional energy interacts with deepening moisture (PWs
increasing to 2-2.25 inches) that will be supported by
southwesterly low level inflow.

As this energy spills farther south, it may help to organize heavy
rainfall across portions of the Tennessee Valley into the southern Appalachians, where a Marginal Risk was introduced for Day 5.
Forecast confidence was limited by model spread, however this may
be an area where a targeted upgrade is required in a future update
if confidence increases.

...Southwest/Great Basin/Central and Southern Rockies...
After what is expected to be a downward trend in convective
coverage and potential flash flooding late in the week (Day 4),
moisture anomalies are forecast to increase again on Saturday. This
increasing moisture along with mid level energy moving around the
southwestern periphery of a broad high will help expand afternoon
and evening storm coverage, including the southern Arizona deserts.

Pereira

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!_neyTR27IQqXEYQIHFA5lcmrXk1AEgSbpAQloxYGM6wvFDGPlzWJk_8m0euDL6z8j5BEnqnJDFtjBRDxLuOidgxGwmY$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!_neyTR27IQqXEYQIHFA5lcmrXk1AEgSbpAQloxYGM6wvFDGPlzWJk_8m0euDL6z8j5BEnqnJDFtjBRDxLuOiL0KBdG8$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!_neyTR27IQqXEYQIHFA5lcmrXk1AEgSbpAQloxYGM6wvFDGPlzWJk_8m0euDL6z8j5BEnqnJDFtjBRDxLuOiCBWMFaY$

$$

= = =
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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Jul 21 16:02:40 2026

FOUS30 KWBC 211602
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1202 PM EDT Tue Jul 21 2026

Day 1
Valid 16Z Tue Jul 21 2026 - 12Z Wed Jul 22 2026

...THERE ARE SLIGHT RISKS OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHWEST AND GREAT BASIN AS WELL AS FOR PORTIONS OF THE OHIO AND
TENNESSEE VALLEYS AND INTO THE NORTHEAST...

...Southwest and Great Basin...

16Z update... All remains in good order, no changes were made.

Campbell

The combination of anomalous monsoonal moisture streaming northward
out of the tropical Pacific and a retrograding upper level
shortwave will create a very active day for thunderstorm activity
this afternoon across much of the Pacific Northwest. Moisture
amounts will be anywhere from 2-4 sigma above normal, with PWATs
above 1.5 inches in southern Arizona, and above 1 inch across much
of the rest of the Southwest. The upper level disturbance tracking
west out of New Mexico will force numerous thunderstorms to form
across Arizona. The storms will slowly track westward. Greater
concentrations of storms are expected along the Mogollon Rim where
topography will help allow the storms to congeal along the Rim. Due
to the above normal amounts of moisture, the storms will be capable
of heavy rainfall with the strongest cores possibly producing
rainfall rates to 2 inches per hour. Given the very favorable
hydrology of the Desert Southwest for flash flooding, given
generally very hydrophobic soils and bare rocks, the Slight Risk
remains in place across much of Arizona, with a higher-end Slight
stretching from the southeast corner of the state northwestward
along the Rim to the Grand Canyon. As usual, slot canyons, dry
washes, and other low-lying areas will be more susceptible to
impactful flash flooding downstream of the heaviest rains.

Further north across the Great Basin, the area will be on the
western periphery of the large ridge over Colorado and a nearly
stationary longwave trough off the coast of northern California. A
separate shortwave trough will track across Nevada and into Idaho
this afternoon. Given similarly anomalous amounts of atmospheric
moisture in place as well across this largely flash-flood prone
area from the Sierras east through Utah, clusters of storms will
form in this area associated with the upper level shortwave.

The inherited Slight was expanded west to include the Sierras,
where upslope will greatly contribute to afternoon and evening
thunderstorm activity there, while the steep slopes will support
fast-forming flash flooding downstream of any heavy rain producing thunderstorms. Elsewhere, few changes were needed, as many of the
areas in the Slight that will be impacted by storms again today
were impacted on previous days, worsening the flash flooding risk.

...Ohio and Tennessee Valleys into the Northeast...

16Z update... The latest CAMs show a modest uptick in QPF across
parts of the Mid-Atlantic and coastal region. As it stands the
Slight Risk in effect already covers locations from the Tennessee
Valley to the Mid-Atlantic/southern parts of the Northeast. There
will likely be pockets of heavier rainfall/hourly rates that will
lead to eastern NC/VA and southeast MD/DE to be on the higher end
of the threat for excessive rainfall and more instances of flash
flooding impacts.

Campbell

Much of the flooding risk across the eastern half of the country
today will be in association with a strong cold front at the
leading edge of a strong longwave trough over the Great Lakes
pushing south and east across the Ohio and Tennessee Valleys as
well as into the Northeast. Anomalous moisture originating in part
from T.S. Bertha in the Gulf will ride northeastward ahead of the
front, providing plentiful moisture for numerous thunderstorms to
form, some of which will produce multiple-inch-per-hour rainfall
rates. A few areas within the broader Slight Risk are likely to
see more rainfall. In central Kentucky and central Tennessee, a southwest-to-northeast oriented band of storms is expected to form
on the leading edge of the cold front, with mesoscale "slow-downs"
in the front's progression allowing for a second round of activity
possibly forming over these same areas where FFGs are depressed
from heavy rainfall in recent days.

The greatest rainfall totals are expected to be across portions of
southeastern Virginia, generally from the Richmond metro east
across the Bay and impacting the lower Maryland and Virginia
sections of the Delmarva. Here, a plume of greater moisture will
interact with the front which will be slowed by its passage across
the mountains. An early to mid afternoon round of storms with the
initial approach of the upper level trough and associated shortwave
energy will move across southern Virginia first. Much more numerous
storms will impact the area in the evening hours as the main front
approaches the area. Despite the loss of daytime heating, the front
is expected to stall over southern Virginia, which could very well
allow for a prolonged period of training storms to set up in the
aforementioned area, which will persist through the overnight. A
short-fused Moderate Risk cannot be ruled out should this evolution
play out as expected by several of the CAMs.

Finally, across the area form northern New Jersey northeast into
the Hudson Valley, morning thunderstorms caught along the Catskills
and Poconos associated with a warm front may start out the day with
a period of training thunderstorms as moisture and instability
levels increase south of the front. This will likely be the feature
that causes the most rainfall in the area. Once the fast-moving
cold front sweeps eastward across the area, resulting in a much
shorter period of widespread thunderstorm activity, its passage
will end the threat for heavy rain in this area for the night.

...Gulf Coast/Tropical Storm Bertha...

16Z update... The bulk of the heaviest rainfall continues to be
forecast offshore the Gulf Coast thus limiting the threat for
impactful flash flooding. No changes were needed to the Marginal
Risk area at this time.

Campbell

As has been the case for several days, the convective pattern with
Bertha in the guidance is little changed. Northeasterly shear will
continue to keep any persistent heavy rainfall well south of the
Gulf Coast for the next several days. Only small and isolated bands
of rain trying to wrap around the center will impact the coast.
The inherited Marginal Risk remains little changed from Louisiana
through the Florida Panhandle.

Wegman

Day 2
Valid 12Z Wed Jul 22 2026 - 12Z Thu Jul 23 2026

...THERE ARE SLIGHT RISKS FOR EXCESSIVE RAINFALL OVER PORTIONS OF
THE INTERMOUNTAIN WEST AS WELL AS FROM NORTHERN GEORGIA THROUGH THE
TIDEWATER OF VIRGINIA AND NORTH CAROLINA...

...Intermountain West...

Highly anomalous amounts of atmospheric moisture associated with
the monsoon over the Intermountain West will be activated by rapid
height falls as an upper level and highly negatively tilted trough
pushes east from off the coast of Washington and Oregon. Meanwhile,
separate upper level energy undercutting the ridge will also
provide additional forcing further east across eastern Idaho and
Wyoming. Once again, numerous thunderstorms will form in the
anomalous moisture and for many areas, will be tied to the local
topography. Few changes were needed with this update. The greatest
amounts of rain look to concentrate in western Wyoming, where any
storms south of Yellowstone could necessitate a higher-end Slight
for some of those areas, as well as for the Uintas of northern
Utah. With nearly all of the forcing further north, the Marginal
Risk into southern Arizona and southern New Mexico was trimmed
significantly with this update, as ridging quickly overtakes this
area and limits convective potential south/west of the Mogollon Rim
as a result.

...Carolinas, Southern Virginia, and Northern Georgia...

A strong cold front running into highly anomalous moisture being
siphoned from the circulation of Tropical Storm Bertha will
exacerbate the gradient of moisture along the frontal interface
through the day across the Carolinas and into southeastern
Virginia. This will work to keep any forward progress of the front
minimal. Storms will train along the front, especially across
northeastern North Carolina and into southeastern Virginia. This
area remains in a higher-end Slight Risk and with the stalled out
front remaining to guide the frequent development of additional
storms, a Moderate Risk upgrade in areas where the storms focused
in the Day 1 period remains a distinct possibility. Guidance has
been laser focused in this area and so forecast changes have been
minimal. Further south and west, however, guidance has become
increasingly optimistic on storms developing further west into the
southern Appalachians. As such, the Slight Risk was expanded west
to include this region from north of Atlanta through the western
Carolinas.

...Tropical Storm Bertha/Gulf Coast...

Strengthening shear across the circulation will continue to keep
any organized convection and meaningful rainfall out over the open
waters of the Gulf. The immediate coastline could still see amounts
greater than an inch, but the rainfall footprint continues to shift
off the coast. In coordination with LIX/Slidell, LA forecast
office, the inherited Slight Risk for this region was downgraded
with this update, with the overall area of the surrounding Marginal
remaining little changed. What little rainfall does impact land
areas remains with the potential to be locally heavy, so
unfortunately no changes to the Marginal Risks can be made so long
as Bertha remains a tropical entity.

Wegman

Day 3
Valid 12Z Thu Jul 23 2026 - 12Z Fri Jul 24 2026

...THERE ARE SLIGHT RISKS FOR EXCESSIVE RAINFALL FOR A PORTION OF
THE SOUTHEAST FROM GEORGIA THROUGH THE CAROLINAS AS WELL AS FOR
NORTHEAST KANSAS AND SOUTHEAST NEBRASKA...

...Southeast...

The stalled out front that has remained across the Southeast will
continue to plague the area with very heavy rainfall, as the
continuous stream of Gulf moisture from the Gulf funnels
northeastward along the front. Yet another day of heavy rain is
expected to impact the Carolinas as a result. The front may drift
ever so slightly further south and east which should clear all but
the Hampton Roads area of far southeast Virginia from the heavy
rainfall threat by Thursday, but for much of eastern North
Carolina, much of South Carolina, and portions of northern Georgia,
generally from Atlanta east, the heavy rainfall threat will
continue through Thursday. Once again, potential for very heavy
rainfall totals in many areas as are expected to see heavy rain
from Wednesday could mean further upgrades to the risks may be
needed, especially across eastern North Carolina. Ultimately, where
the heaviest rain falls both today and Wednesday should dictate if
further upgrades will be needed.

...Central Plains...

An MCS is expected to impact a portion of northeast Kansas,
southeast Nebraska and the Kansas City and St. Joseph metros on
Thursday. The heavy rainfall footprint has drifted south and west,
so the Slight Risk has been adjusted accordingly. As with many
MCS's the location of the heaviest rain is likely to continue
shifting with future updates, most likely towards the south, so
stay tuned for further updates. Periods of heavy rain may continue
to impact Wyoming into Colorado as well, where upgrades to a Slight
are also probable, depending on where the heavy rains from
Wednesday overlap with Thursday's forecast.

...Bertha...

Bertha, who may no longer be a tropical cyclone by Thursday, and
likely to be in a weakening state, should continue to keep any
associated rainfall off the coast. The immediate coast remains with
the best chance for seeing anything over an inch of associated
rainfall. FFGs are significantly higher than that in all areas.
Given this, and with very good consistency in this scenario in the
guidance, the inherited Slight and Marginal for a portion of the
Texas and Louisiana Gulf coasts was removed with this update. The
Marginal Risk has been downgraded to under a 5% risk for the upper
Texas Gulf Coast, as well as the Slight for coastal Louisiana
downgraded to a Marginal with this update.

Wegman

Day 4 and Day 5

Valid 12Z Fri Jul 24 2026 - 12Z Sun Jul 26 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
LOWER MISSOURI VALLEY AND MID MISSISSIPPI VALLEYS ON DAY 4 AND FOR
PARTS OF SOUTHEAST COAST DAYS 4 AND 5...

...Southeast...
A multi-day rainfall event is expected to continue into the
weekend, with additional heavy rains likely, especially for parts
of southeastern Virginia and the Carolinas. The focus for these
rains will be a slow-moving, moisture-laden front that is forecast
to linger across the region through at least the first half of the
weekend. Southwesterly flow ahead of a shortwave trough moving
through the Ohio/Tennessee valleys will further fortify the already moisture-rich airmass, with models showing PWs increasing in
excess of 2.25 inches (+2 to 3 sigma). This moisture, along with
pockets of enhanced ascent afforded by mid-level energy, will
support periods of heavy, highly-efficient rainfall. While areas of
heavy rainfall are likely, forecast confidence regarding their
placement remains limited due to continuing model spread with
regards to the placement of the front, which will have impacts on
where the heaviest amounts occur.

...Gulf Coast...
Northeasterly shear and dry air north of the center should keep
much of the heavy rainfall threat associated with T.S. Bertha out
over the open waters. Also, there is some question regarding the
intensity of the system and if it will retain a closed circulation
as it moves from the Louisiana onto the upper Texas coasts early in
the period. However, cannot not rule out an isolated threat for
heavy rainfall and therefore maintained a Marginal Risk for now
from the southwestern Louisiana to the upper Texas coasts on Day 4.

...Lower Missouri-Mid Mississippi to the Tennessee Valleys/Southern Appalachians...
Ongoing storms associated with pooling moisture along a low-level
boundary and ahead a mid-level shortwave dropping southeast may
continue to support storms and the threat for heavy rains Friday
morning (Day 4) across parts of the lower Missouri Valley. Storms
are expected to wane by late in the morning, but there remains a
model signal for new storms developing farther to the south and
east as additional energy interacts with deepening moisture (PWs
increasing to 2-2.25 inches) that will be supported by
southwesterly low level inflow.

As this energy spills farther south, it may help to organize heavy
rainfall across portions of the Tennessee Valley into the southern Appalachians, where a Marginal Risk was introduced for Day 5.
Forecast confidence was limited by model spread, however this may
be an area where a targeted upgrade is required in a future update
if confidence increases.

...Southwest/Great Basin/Central and Southern Rockies...
After what is expected to be a downward trend in convective
coverage and potential flash flooding late in the week (Day 4),
moisture anomalies are forecast to increase again on Saturday. This
increasing moisture along with mid level energy moving around the
southwestern periphery of a broad high will help expand afternoon
and evening storm coverage, including the southern Arizona deserts.

Pereira

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!7AO3W7mel_sCSEVp4Z_DEQY96XTgQStOdjeGlq17ayCXJfOxq91L28d4Mbv5zBMN5W2H1cFOuKW2WVgrXLxRfx1rBIc$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!7AO3W7mel_sCSEVp4Z_DEQY96XTgQStOdjeGlq17ayCXJfOxq91L28d4Mbv5zBMN5W2H1cFOuKW2WVgrXLxRSdk5E0w$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!7AO3W7mel_sCSEVp4Z_DEQY96XTgQStOdjeGlq17ayCXJfOxq91L28d4Mbv5zBMN5W2H1cFOuKW2WVgrXLxRWTeKV3U$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Jul 21 19:46:54 2026

FOUS30 KWBC 211946
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
346 PM EDT Tue Jul 21 2026

Day 1
Valid 16Z Tue Jul 21 2026 - 12Z Wed Jul 22 2026

...THERE ARE SLIGHT RISKS OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHWEST AND GREAT BASIN AS WELL AS FOR PORTIONS OF THE OHIO AND
TENNESSEE VALLEYS AND INTO THE NORTHEAST...

...Southwest and Great Basin...

16Z update... All remains in good order, no changes were made.

Campbell

The combination of anomalous monsoonal moisture streaming northward
out of the tropical Pacific and a retrograding upper level
shortwave will create a very active day for thunderstorm activity
this afternoon across much of the Pacific Northwest. Moisture
amounts will be anywhere from 2-4 sigma above normal, with PWATs
above 1.5 inches in southern Arizona, and above 1 inch across much
of the rest of the Southwest. The upper level disturbance tracking
west out of New Mexico will force numerous thunderstorms to form
across Arizona. The storms will slowly track westward. Greater
concentrations of storms are expected along the Mogollon Rim where
topography will help allow the storms to congeal along the Rim. Due
to the above normal amounts of moisture, the storms will be capable
of heavy rainfall with the strongest cores possibly producing
rainfall rates to 2 inches per hour. Given the very favorable
hydrology of the Desert Southwest for flash flooding, given
generally very hydrophobic soils and bare rocks, the Slight Risk
remains in place across much of Arizona, with a higher-end Slight
stretching from the southeast corner of the state northwestward
along the Rim to the Grand Canyon. As usual, slot canyons, dry
washes, and other low-lying areas will be more susceptible to
impactful flash flooding downstream of the heaviest rains.

Further north across the Great Basin, the area will be on the
western periphery of the large ridge over Colorado and a nearly
stationary longwave trough off the coast of northern California. A
separate shortwave trough will track across Nevada and into Idaho
this afternoon. Given similarly anomalous amounts of atmospheric
moisture in place as well across this largely flash-flood prone
area from the Sierras east through Utah, clusters of storms will
form in this area associated with the upper level shortwave.

The inherited Slight was expanded west to include the Sierras,
where upslope will greatly contribute to afternoon and evening
thunderstorm activity there, while the steep slopes will support
fast-forming flash flooding downstream of any heavy rain producing thunderstorms. Elsewhere, few changes were needed, as many of the
areas in the Slight that will be impacted by storms again today
were impacted on previous days, worsening the flash flooding risk.

...Ohio and Tennessee Valleys into the Northeast...

16Z update... The latest CAMs show a modest uptick in QPF across
parts of the Mid-Atlantic and coastal region. As it stands the
Slight Risk in effect already covers locations from the Tennessee
Valley to the Mid-Atlantic/southern parts of the Northeast. There
will likely be pockets of heavier rainfall/hourly rates that will
lead to eastern NC/VA and southeast MD/DE to be on the higher end
of the threat for excessive rainfall and more instances of flash
flooding impacts.

Campbell

Much of the flooding risk across the eastern half of the country
today will be in association with a strong cold front at the
leading edge of a strong longwave trough over the Great Lakes
pushing south and east across the Ohio and Tennessee Valleys as
well as into the Northeast. Anomalous moisture originating in part
from T.S. Bertha in the Gulf will ride northeastward ahead of the
front, providing plentiful moisture for numerous thunderstorms to
form, some of which will produce multiple-inch-per-hour rainfall
rates. A few areas within the broader Slight Risk are likely to
see more rainfall. In central Kentucky and central Tennessee, a southwest-to-northeast oriented band of storms is expected to form
on the leading edge of the cold front, with mesoscale "slow-downs"
in the front's progression allowing for a second round of activity
possibly forming over these same areas where FFGs are depressed
from heavy rainfall in recent days.

The greatest rainfall totals are expected to be across portions of
southeastern Virginia, generally from the Richmond metro east
across the Bay and impacting the lower Maryland and Virginia
sections of the Delmarva. Here, a plume of greater moisture will
interact with the front which will be slowed by its passage across
the mountains. An early to mid afternoon round of storms with the
initial approach of the upper level trough and associated shortwave
energy will move across southern Virginia first. Much more numerous
storms will impact the area in the evening hours as the main front
approaches the area. Despite the loss of daytime heating, the front
is expected to stall over southern Virginia, which could very well
allow for a prolonged period of training storms to set up in the
aforementioned area, which will persist through the overnight. A
short-fused Moderate Risk cannot be ruled out should this evolution
play out as expected by several of the CAMs.

Finally, across the area form northern New Jersey northeast into
the Hudson Valley, morning thunderstorms caught along the Catskills
and Poconos associated with a warm front may start out the day with
a period of training thunderstorms as moisture and instability
levels increase south of the front. This will likely be the feature
that causes the most rainfall in the area. Once the fast-moving
cold front sweeps eastward across the area, resulting in a much
shorter period of widespread thunderstorm activity, its passage
will end the threat for heavy rain in this area for the night.

...Gulf Coast/Tropical Storm Bertha...

16Z update... The bulk of the heaviest rainfall continues to be
forecast offshore the Gulf Coast thus limiting the threat for
impactful flash flooding. No changes were needed to the Marginal
Risk area at this time.

Campbell

As has been the case for several days, the convective pattern with
Bertha in the guidance is little changed. Northeasterly shear will
continue to keep any persistent heavy rainfall well south of the
Gulf Coast for the next several days. Only small and isolated bands
of rain trying to wrap around the center will impact the coast.
The inherited Marginal Risk remains little changed from Louisiana
through the Florida Panhandle.

Wegman

Day 2
Valid 12Z Wed Jul 22 2026 - 12Z Thu Jul 23 2026

...THERE IS A MODERATE RISK FOR EXCESSIVE RAINFALL OVER PORTIONS
THE TIDEWATER OF VIRGINIA AND NORTH CAROLINA...

...Carolinas, Southern Virginia, and Northern Georgia...

21Z update... Given the steady influx of tropical moisture from
T.S. Bertha northeastward into the sinking strong cold front,
widespread convection with embedded heavy rainfall will focus over
North Carolina and Virginia Tidewater region. There is a signal for
2 to 4 inches for this part of the country and rainfall rates could
easily exceed 1.5/2 inches per hour. Training/repeating of storms
expected along the frontal boundary therefore a Moderate Risk was
raised for this period.

Campbell

A strong cold front running into highly anomalous moisture being
siphoned from the circulation of Tropical Storm Bertha will
exacerbate the gradient of moisture along the frontal interface
through the day across the Carolinas and into southeastern
Virginia. This will work to keep any forward progress of the front
minimal. Storms will train along the front, especially across
northeastern North Carolina and into southeastern Virginia. This
area remains in a higher-end Slight Risk and with the stalled out
front remaining to guide the frequent development of additional
storms, a Moderate Risk upgrade in areas where the storms focused
in the Day 1 period remains a distinct possibility. Guidance has
been laser focused in this area and so forecast changes have been
minimal. Further south and west, however, guidance has become
increasingly optimistic on storms developing further west into the
southern Appalachians. As such, the Slight Risk was expanded west
to include this region from north of Atlanta through the western
Carolinas.

...Intermountain West...

21z update... Minor expansions of the Marginal Risk were made
across north-central Arizona and eastern Kansas to reflect the new
WPC QPF placement. The latest CAMs indicated a modest uptick in
convection for north-central and southeast Wyoming and northeast of
Boulder Colorado, which was just outside the inherited Slight Risk
area. Therefore eastward adjustments were made to the Slight Risk
area.

Campbell

Highly anomalous amounts of atmospheric moisture associated with
the monsoon over the Intermountain West will be activated by rapid
height falls as an upper level and highly negatively tilted trough
pushes east from off the coast of Washington and Oregon. Meanwhile,
separate upper level energy undercutting the ridge will also
provide additional forcing further east across eastern Idaho and
Wyoming. Once again, numerous thunderstorms will form in the
anomalous moisture and for many areas, will be tied to the local
topography. Few changes were needed with this update. The greatest
amounts of rain look to concentrate in western Wyoming, where any
storms south of Yellowstone could necessitate a higher-end Slight
for some of those areas, as well as for the Uintas of northern
Utah. With nearly all of the forcing further north, the Marginal
Risk into southern Arizona and southern New Mexico was trimmed
significantly with this update, as ridging quickly overtakes this
area and limits convective potential south/west of the Mogollon Rim
as a result.

...Tropical Storm Bertha/Gulf Coast...

Strengthening shear across the circulation will continue to keep
any organized convection and meaningful rainfall out over the open
waters of the Gulf. The immediate coastline could still see amounts
greater than an inch, but the rainfall footprint continues to shift
off the coast. In coordination with LIX/Slidell, LA forecast
office, the inherited Slight Risk for this region was downgraded
with this update, with the overall area of the surrounding Marginal
remaining little changed. What little rainfall does impact land
areas remains with the potential to be locally heavy, so
unfortunately no changes to the Marginal Risks can be made so long
as Bertha remains a tropical entity.

Wegman

Day 3
Valid 12Z Thu Jul 23 2026 - 12Z Fri Jul 24 2026

...THERE IS A MODERATE RISK FOR EXCESSIVE RAINFALL OVER PORTIONS
NORTH CAROLINA...

...Southeast...

21Z update... The heavy rainfall mentioned for the Day 2 period
will persist across North Carolina and surrounding locations as the
tropical moisture continues to interact with the stalled frontal
boundary. Training/repeating of storms will focus an additional 2
to 4+ inches over North Carolina and portions of southern/southeast
Virgina bringing the 48-hr forecast of 4 to 9+ inches for the
region. There will likely be a fair amount of overlap in the QPF
footprint from the D2 period, which will already be well saturated
prior to this period. A Moderate was also raised central and
east/northeast North Carolina as scattered to widespread instances
of flash flooding is expected.

Campbell

The stalled out front that has remained across the Southeast will
continue to plague the area with very heavy rainfall, as the
continuous stream of Gulf moisture from the Gulf funnels
northeastward along the front. Yet another day of heavy rain is
expected to impact the Carolinas as a result. The front may drift
ever so slightly further south and east which should clear all but
the Hampton Roads area of far southeast Virginia from the heavy
rainfall threat by Thursday, but for much of eastern North
Carolina, much of South Carolina, and portions of northern Georgia,
generally from Atlanta east, the heavy rainfall threat will
continue through Thursday. Once again, potential for very heavy
rainfall totals in many areas as are expected to see heavy rain
from Wednesday could mean further upgrades to the risks may be
needed, especially across eastern North Carolina. Ultimately, where
the heaviest rain falls both today and Wednesday should dictate if
further upgrades will be needed.

...Central Plains...

An MCS is expected to impact a portion of northeast Kansas,
southeast Nebraska and the Kansas City and St. Joseph metros on
Thursday. The heavy rainfall footprint has drifted south and west,
so the Slight Risk has been adjusted accordingly. As with many
MCS's the location of the heaviest rain is likely to continue
shifting with future updates, most likely towards the south, so
stay tuned for further updates. Periods of heavy rain may continue
to impact Wyoming into Colorado as well, where upgrades to a Slight
are also probable, depending on where the heavy rains from
Wednesday overlap with Thursday's forecast.

...Bertha...

21Z update... Rainfall trends across far southeast Texas have
trended down with the latest guidance thus the threat for isolated
flash flooding has reduced as well. The Marginal Risk was trimmed
out of Texas for this period.

Campbell

Bertha, who may no longer be a tropical cyclone by Thursday, and
likely to be in a weakening state, should continue to keep any
associated rainfall off the coast. The immediate coast remains with
the best chance for seeing anything over an inch of associated
rainfall. FFGs are significantly higher than that in all areas.
Given this, and with very good consistency in this scenario in the
guidance, the inherited Slight and Marginal for a portion of the
Texas and Louisiana Gulf coasts was removed with this update. The
Marginal Risk has been downgraded to under a 5% risk for the upper
Texas Gulf Coast, as well as the Slight for coastal Louisiana
downgraded to a Marginal with this update.

Wegman

Day 4 and Day 5

Valid 12Z Fri Jul 24 2026 - 12Z Sun Jul 26 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR MISSOURI ON
DAY 4 AND FOR PARTS OF THE CAROLINAS DAYS 4 AND 5...

...Southeast...
The multi-day rainfall event continues into the weekend, with
additional heavy rains likely, especially for the Carolinas. The
focus for these rains will be a slow-moving, moisture-laden front
that is forecast to linger across the region through at least the
first half of the weekend. Southwesterly flow ahead of a shortwave
trough moving through the Ohio/Tennessee valleys will further
fortify the already moisture- rich airmass, with models showing PWs
increasing in excess of 2.25 inches (+2 to 3 sigma). This
moisture, along with pockets of enhanced ascent afforded by mid-
level energy, will support periods of heavy, highly-efficient
rainfall. While areas of heavy rainfall are likely, forecast
confidence regarding their placement remains limited due to
continuing model spread with regards to the placement of the front,
which will have impacts on where the heaviest amounts occur. Slight
Risks are expanded west to include both central and eastern
sections of the Carolinas for both Days 4 and 5.

...Missouri to the Tennessee Valleys/Southern Appalachians...
There should be some ongoing activity over Missouri Friday morning
with greater confidence on a more vigorous setup over much of
Missouri after peak diurnal Friday afternoon/evening. PW increases
to 2-2.25 inches with support from southwesterly low level inflow
and potential frontal boundaries. The Day 4 Slight Risk was
expanded a bit over Missouri.

Farther south, frontal forcing will help focus diurnal convection
over northern AL/GA east into South Carolina with a Day 4 Marginal
Risk now connected from Missouri to the Carolinas along this
frontal boundary.

The Day 5 Marginal Risk was refocused to be along the continued
frontal boundary from southeast Missouri through the Tennessee
Valley instead of to the Gulf Coast. Given this larger change,
please be on the lookout for further refinement.

...Southwest/Great Basin/Central and Southern Rockies...
A downward trend in convective coverage and potential flash
flooding late is forecast for Friday with a Marginal Risk limited
to terrain around the Four Corners. Moisture anomalies then
increase again for Saturday which along with mid level energy
moving around the southwestern periphery of a broad high will help
expand afternoon and evening storm coverage. A broader Marginal is
in effect for Day 5, including the southern Arizona deserts and the
majority of the Four Corners states into eastern Nevada. WFOs ABQ
and EPZ were concerned about mid level warmth/capping when asked
about a Day 5 Slight for the Sangre de Cristo/Sacramento, so that
remains a Marginal at this time.

...Gulf Coast...
Confidence has increased on heavy rain associated with Bertha
remaining away from the Texas and Gulf Coasts on Friday to warrant
removal of the Day 4 Marginal from Texas. Further more, frontal
related rainfall both Friday and Saturday is now focused far enough
inland to not have A Marginal Risk on the coast for either day.

Jackson/Pereira

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!48Cfqnhx15TLsLqdGgrSn3wQ_MNzfUXyE99hifB0ZigoDppw5ZzjwDs-c_hM-FCfacB2nNowPL4CM7BcAga-74fOagU$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!48Cfqnhx15TLsLqdGgrSn3wQ_MNzfUXyE99hifB0ZigoDppw5ZzjwDs-c_hM-FCfacB2nNowPL4CM7BcAga-GzfIBEU$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!48Cfqnhx15TLsLqdGgrSn3wQ_MNzfUXyE99hifB0ZigoDppw5ZzjwDs-c_hM-FCfacB2nNowPL4CM7BcAga-VizD38w$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Jul 21 22:20:52 2026

FOUS30 KWBC 212220
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
620 PM EDT Tue Jul 21 2026

Day 1
Valid 01Z Wed Jul 22 2026 - 12Z Wed Jul 22 2026

...THERE ARE SLIGHT RISKS OF EXCESSIVE RAINFALL FOR MUCH OF THE
SOUTHWEST AND GREAT BASIN AS WELL AS MUCH OF THE OHIO AND
TENNESSEE VALLEYS THROUGH THE MID-ATLANTIC AND INTO NEW ENGLAND...

...Ohio and Tennessee Valleys, Mid-Atlantic, into the Northeast...

22Z Update...Enhanced flash flooding case this evening from the
central Appalachians through the Baltimore-Washington metro onto
the Delmarva peninsula. This is from ample moisture streaming north
from Bertha with an approaching strong cold front over the Ohio
Valley.

Slight Risk remains in effect for much of the same areas as before.
More of the Mid-Atlantic are now considered to have a greater,
more enhanced risk than before (the higher end of the Slight
category). The main threat timing is now through midnight, holding
longer down the VA portion of the Chesapeake Bay overnight.

Jackson

Previous discussion...

Much of the flooding risk across the eastern half of the country
today will be in association with a strong cold front at the
leading edge of a strong longwave trough over the Great Lakes
pushing south and east across the Ohio and Tennessee Valleys as
well as into the Northeast. Anomalous moisture originating in part
from T.S. Bertha in the Gulf will ride northeastward ahead of the
front, providing plentiful moisture for numerous thunderstorms to
form, some of which will produce multiple-inch-per-hour rainfall
rates. A few areas within the broader Slight Risk are likely to
see more rainfall. In central Kentucky and central Tennessee, a southwest-to-northeast oriented band of storms is expected to form
on the leading edge of the cold front, with mesoscale "slow-downs"
in the front's progression allowing for a second round of activity
possibly forming over these same areas where FFGs are depressed
from heavy rainfall in recent days.

The greatest rainfall totals are expected to be across portions of
southeastern Virginia, generally from the Richmond metro east
across the Bay and impacting the lower Maryland and Virginia
sections of the Delmarva. Here, a plume of greater moisture will
interact with the front which will be slowed by its passage across
the mountains. An early to mid afternoon round of storms with the
initial approach of the upper level trough and associated shortwave
energy will move across southern Virginia first. Much more numerous
storms will impact the area in the evening hours as the main front
approaches the area. Despite the loss of daytime heating, the front
is expected to stall over southern Virginia, which could very well
allow for a prolonged period of training storms to set up in the
aforementioned area, which will persist through the overnight. A
short-fused Moderate Risk cannot be ruled out should this evolution
play out as expected by several of the CAMs.

Finally, across the area form northern New Jersey northeast into
the Hudson Valley, morning thunderstorms caught along the Catskills
and Poconos associated with a warm front may start out the day with
a period of training thunderstorms as moisture and instability
levels increase south of the front. This will likely be the feature
that causes the most rainfall in the area. Once the fast-moving
cold front sweeps eastward across the area, resulting in a much
shorter period of widespread thunderstorm activity, its passage
will end the threat for heavy rain in this area for the night.

...Southwest and Great Basin...

16Z update... All remains in good order, no changes were made.

Campbell

The combination of anomalous monsoonal moisture streaming northward
out of the tropical Pacific and a retrograding upper level
shortwave will create a very active day for thunderstorm activity
this afternoon across much of the Pacific Northwest. Moisture
amounts will be anywhere from 2-4 sigma above normal, with PWATs
above 1.5 inches in southern Arizona, and above 1 inch across much
of the rest of the Southwest. The upper level disturbance tracking
west out of New Mexico will force numerous thunderstorms to form
across Arizona. The storms will slowly track westward. Greater
concentrations of storms are expected along the Mogollon Rim where
topography will help allow the storms to congeal along the Rim. Due
to the above normal amounts of moisture, the storms will be capable
of heavy rainfall with the strongest cores possibly producing
rainfall rates to 2 inches per hour. Given the very favorable
hydrology of the Desert Southwest for flash flooding, given
generally very hydrophobic soils and bare rocks, the Slight Risk
remains in place across much of Arizona, with a higher-end Slight
stretching from the southeast corner of the state northwestward
along the Rim to the Grand Canyon. As usual, slot canyons, dry
washes, and other low-lying areas will be more susceptible to
impactful flash flooding downstream of the heaviest rains.

Further north across the Great Basin, the area will be on the
western periphery of the large ridge over Colorado and a nearly
stationary longwave trough off the coast of northern California. A
separate shortwave trough will track across Nevada and into Idaho
this afternoon. Given similarly anomalous amounts of atmospheric
moisture in place as well across this largely flash-flood prone
area from the Sierras east through Utah, clusters of storms will
form in this area associated with the upper level shortwave.

The inherited Slight was expanded west to include the Sierras,
where upslope will greatly contribute to afternoon and evening
thunderstorm activity there, while the steep slopes will support
fast-forming flash flooding downstream of any heavy rain producing thunderstorms. Elsewhere, few changes were needed, as many of the
areas in the Slight that will be impacted by storms again today
were impacted on previous days, worsening the flash flooding risk.

...Gulf Coast/Tropical Storm Bertha...

16Z update... The bulk of the heaviest rainfall continues to be
forecast offshore the Gulf Coast thus limiting the threat for
impactful flash flooding. No changes were needed to the Marginal
Risk area at this time.

Campbell

As has been the case for several days, the convective pattern with
Bertha in the guidance is little changed. Northeasterly shear will
continue to keep any persistent heavy rainfall well south of the
Gulf Coast for the next several days. Only small and isolated bands
of rain trying to wrap around the center will impact the coast.
The inherited Marginal Risk remains little changed from Louisiana
through the Florida Panhandle.

Wegman

Day 2
Valid 12Z Wed Jul 22 2026 - 12Z Thu Jul 23 2026

...THERE IS A MODERATE RISK FOR EXCESSIVE RAINFALL OVER PORTIONS
THE TIDEWATER OF VIRGINIA AND NORTH CAROLINA...

...Carolinas, Southern Virginia, and Northern Georgia...

21Z update... Given the steady influx of tropical moisture from
T.S. Bertha northeastward into the sinking strong cold front,
widespread convection with embedded heavy rainfall will focus over
North Carolina and Virginia Tidewater region. There is a signal for
2 to 4 inches for this part of the country and rainfall rates could
easily exceed 1.5/2 inches per hour. Training/repeating of storms
expected along the frontal boundary therefore a Moderate Risk was
raised for this period.

Campbell

A strong cold front running into highly anomalous moisture being
siphoned from the circulation of Tropical Storm Bertha will
exacerbate the gradient of moisture along the frontal interface
through the day across the Carolinas and into southeastern
Virginia. This will work to keep any forward progress of the front
minimal. Storms will train along the front, especially across
northeastern North Carolina and into southeastern Virginia. This
area remains in a higher-end Slight Risk and with the stalled out
front remaining to guide the frequent development of additional
storms, a Moderate Risk upgrade in areas where the storms focused
in the Day 1 period remains a distinct possibility. Guidance has
been laser focused in this area and so forecast changes have been
minimal. Further south and west, however, guidance has become
increasingly optimistic on storms developing further west into the
southern Appalachians. As such, the Slight Risk was expanded west
to include this region from north of Atlanta through the western
Carolinas.

...Intermountain West...

21z update... Minor expansions of the Marginal Risk were made
across north-central Arizona and eastern Kansas to reflect the new
WPC QPF placement. The latest CAMs indicated a modest uptick in
convection for north-central and southeast Wyoming and northeast of
Boulder Colorado, which was just outside the inherited Slight Risk
area. Therefore eastward adjustments were made to the Slight Risk
area.

Campbell

Highly anomalous amounts of atmospheric moisture associated with
the monsoon over the Intermountain West will be activated by rapid
height falls as an upper level and highly negatively tilted trough
pushes east from off the coast of Washington and Oregon. Meanwhile,
separate upper level energy undercutting the ridge will also
provide additional forcing further east across eastern Idaho and
Wyoming. Once again, numerous thunderstorms will form in the
anomalous moisture and for many areas, will be tied to the local
topography. Few changes were needed with this update. The greatest
amounts of rain look to concentrate in western Wyoming, where any
storms south of Yellowstone could necessitate a higher-end Slight
for some of those areas, as well as for the Uintas of northern
Utah. With nearly all of the forcing further north, the Marginal
Risk into southern Arizona and southern New Mexico was trimmed
significantly with this update, as ridging quickly overtakes this
area and limits convective potential south/west of the Mogollon Rim
as a result.

...Tropical Storm Bertha/Gulf Coast...

Strengthening shear across the circulation will continue to keep
any organized convection and meaningful rainfall out over the open
waters of the Gulf. The immediate coastline could still see amounts
greater than an inch, but the rainfall footprint continues to shift
off the coast. In coordination with LIX/Slidell, LA forecast
office, the inherited Slight Risk for this region was downgraded
with this update, with the overall area of the surrounding Marginal
remaining little changed. What little rainfall does impact land
areas remains with the potential to be locally heavy, so
unfortunately no changes to the Marginal Risks can be made so long
as Bertha remains a tropical entity.

Wegman

Day 3
Valid 12Z Thu Jul 23 2026 - 12Z Fri Jul 24 2026

...THERE IS A MODERATE RISK FOR EXCESSIVE RAINFALL OVER PORTIONS
NORTH CAROLINA...

...Southeast...

21Z update... The heavy rainfall mentioned for the Day 2 period
will persist across North Carolina and surrounding locations as the
tropical moisture continues to interact with the stalled frontal
boundary. Training/repeating of storms will focus an additional 2
to 4+ inches over North Carolina and portions of southern/southeast
Virgina bringing the 48-hr forecast of 4 to 9+ inches for the
region. There will likely be a fair amount of overlap in the QPF
footprint from the D2 period, which will already be well saturated
prior to this period. A Moderate was also raised central and
east/northeast North Carolina as scattered to widespread instances
of flash flooding is expected.

Campbell

The stalled out front that has remained across the Southeast will
continue to plague the area with very heavy rainfall, as the
continuous stream of Gulf moisture from the Gulf funnels
northeastward along the front. Yet another day of heavy rain is
expected to impact the Carolinas as a result. The front may drift
ever so slightly further south and east which should clear all but
the Hampton Roads area of far southeast Virginia from the heavy
rainfall threat by Thursday, but for much of eastern North
Carolina, much of South Carolina, and portions of northern Georgia,
generally from Atlanta east, the heavy rainfall threat will
continue through Thursday. Once again, potential for very heavy
rainfall totals in many areas as are expected to see heavy rain
from Wednesday could mean further upgrades to the risks may be
needed, especially across eastern North Carolina. Ultimately, where
the heaviest rain falls both today and Wednesday should dictate if
further upgrades will be needed.

...Central Plains...

An MCS is expected to impact a portion of northeast Kansas,
southeast Nebraska and the Kansas City and St. Joseph metros on
Thursday. The heavy rainfall footprint has drifted south and west,
so the Slight Risk has been adjusted accordingly. As with many
MCS's the location of the heaviest rain is likely to continue
shifting with future updates, most likely towards the south, so
stay tuned for further updates. Periods of heavy rain may continue
to impact Wyoming into Colorado as well, where upgrades to a Slight
are also probable, depending on where the heavy rains from
Wednesday overlap with Thursday's forecast.

...Bertha...

21Z update... Rainfall trends across far southeast Texas have
trended down with the latest guidance thus the threat for isolated
flash flooding has reduced as well. The Marginal Risk was trimmed
out of Texas for this period.

Campbell

Bertha, who may no longer be a tropical cyclone by Thursday, and
likely to be in a weakening state, should continue to keep any
associated rainfall off the coast. The immediate coast remains with
the best chance for seeing anything over an inch of associated
rainfall. FFGs are significantly higher than that in all areas.
Given this, and with very good consistency in this scenario in the
guidance, the inherited Slight and Marginal for a portion of the
Texas and Louisiana Gulf coasts was removed with this update. The
Marginal Risk has been downgraded to under a 5% risk for the upper
Texas Gulf Coast, as well as the Slight for coastal Louisiana
downgraded to a Marginal with this update.

Wegman

Day 4 and Day 5

Valid 12Z Fri Jul 24 2026 - 12Z Sun Jul 26 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR MISSOURI ON
DAY 4 AND FOR PARTS OF THE CAROLINAS DAYS 4 AND 5...

...Southeast...
The multi-day rainfall event continues into the weekend, with
additional heavy rains likely, especially for the Carolinas. The
focus for these rains will be a slow-moving, moisture-laden front
that is forecast to linger across the region through at least the
first half of the weekend. Southwesterly flow ahead of a shortwave
trough moving through the Ohio/Tennessee valleys will further
fortify the already moisture- rich airmass, with models showing PWs
increasing in excess of 2.25 inches (+2 to 3 sigma). This
moisture, along with pockets of enhanced ascent afforded by mid-
level energy, will support periods of heavy, highly-efficient
rainfall. While areas of heavy rainfall are likely, forecast
confidence regarding their placement remains limited due to
continuing model spread with regards to the placement of the front,
which will have impacts on where the heaviest amounts occur. Slight
Risks are expanded west to include both central and eastern
sections of the Carolinas for both Days 4 and 5.

...Missouri to the Tennessee Valleys/Southern Appalachians...
There should be some ongoing activity over Missouri Friday morning
with greater confidence on a more vigorous setup over much of
Missouri after peak diurnal Friday afternoon/evening. PW increases
to 2-2.25 inches with support from southwesterly low level inflow
and potential frontal boundaries. The Day 4 Slight Risk was
expanded a bit over Missouri.

Farther south, frontal forcing will help focus diurnal convection
over northern AL/GA east into South Carolina with a Day 4 Marginal
Risk now connected from Missouri to the Carolinas along this
frontal boundary.

The Day 5 Marginal Risk was refocused to be along the continued
frontal boundary from southeast Missouri through the Tennessee
Valley instead of to the Gulf Coast. Given this larger change,
please be on the lookout for further refinement.

...Southwest/Great Basin/Central and Southern Rockies...
A downward trend in convective coverage and potential flash
flooding late is forecast for Friday with a Marginal Risk limited
to terrain around the Four Corners. Moisture anomalies then
increase again for Saturday which along with mid level energy
moving around the southwestern periphery of a broad high will help
expand afternoon and evening storm coverage. A broader Marginal is
in effect for Day 5, including the southern Arizona deserts and the
majority of the Four Corners states into eastern Nevada. WFOs ABQ
and EPZ were concerned about mid level warmth/capping when asked
about a Day 5 Slight for the Sangre de Cristo/Sacramento, so that
remains a Marginal at this time.

...Gulf Coast...
Confidence has increased on heavy rain associated with Bertha
remaining away from the Texas and Gulf Coasts on Friday to warrant
removal of the Day 4 Marginal from Texas. Further more, frontal
related rainfall both Friday and Saturday is now focused far enough
inland to not have A Marginal Risk on the coast for either day.

Jackson/Pereira

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!5O9BvFzhx8v7IjUluoZVBVWoe7Jzv5v2F-AeCnbxG6g6Z3sOiCwNSmsXwAKVLuCCamIWqnqesfAec9YvzcsfawHKjAY$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!5O9BvFzhx8v7IjUluoZVBVWoe7Jzv5v2F-AeCnbxG6g6Z3sOiCwNSmsXwAKVLuCCamIWqnqesfAec9YvzcsfVaZZKU0$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!5O9BvFzhx8v7IjUluoZVBVWoe7Jzv5v2F-AeCnbxG6g6Z3sOiCwNSmsXwAKVLuCCamIWqnqesfAec9Yvzcsf8iZnPX4$

$$

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* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Jul 22 00:40:48 2026

FOUS30 KWBC 220033
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
833 PM EDT Tue Jul 21 2026

Day 1
Valid 01Z Wed Jul 22 2026 - 12Z Wed Jul 22 2026

...THERE ARE SLIGHT RISKS OF EXCESSIVE RAINFALL FOR MUCH OF THE
SOUTHWEST AND GREAT BASIN AS WELL AS MUCH OF THE OHIO AND
TENNESSEE VALLEYS THROUGH THE MID-ATLANTIC AND INTO NEW ENGLAND...

...Ohio and Tennessee Valleys, Mid-Atlantic, into the Northeast...

Strong cold front under a potent upper trough continues to push
across the Ohio River with prefrontal activity training at times
early this evening over West Virginia and Kentucky. This activity
shifts over the Mid-Atlantic and Tennessee rest of this evening and
lingers over the Delmarva and probably eastern Virginia overnight.
Ample moisture that streamed up from Bertha is present over the
region with PW over 2", peaking at 2.5" over north-central TN as of
00Z. Most activity has been progressive, but orientation to
direction of motion has been problematic. Scattered flash flooding
continues for the Mid-Atlantic, southern Appalachians, and
Tennessee overnight where a Slight Risk remains. This is considered
to be a higher end (or "enhanced") over the central Mid-Atlantic
and over middle/eastern Tennessee. There is some activity back
with the surface front back over central Ohio, so the Slight Risk
is maintained behind the prefrontal activity.

Poleward motion ahead of the front/upper trough maintains some
activity over the northern Mid-Atlantic and southern New England
where a general Slight Risk remains in effect.

Recent HRRR and RRFS runs seem to be on track with the activity
across this region. MPDs will continue to be issued, so please
consult them for further information overnight.

...Southwest and Great Basin...

Monsoonal activity continues this evening, most vigorously over the
Mogollon Rim in Arizona and over southeast Utah which is downstream
of a persistent mid-level low over the central AZ/NM border.
Earlier activity along the Sierra Nevada has shifted east onto the
Great Basin with more isolated flash flood threats there through
northern Utah into the northern/central Rockies overnight. Recent
HRRR/RRFS runs have a decent handle on activity with MPDs
continuing to be issued for the notable threats.

...Gulf Coast/Tropical Storm Bertha...

Thin bands of rain continue overnight for the Florida Panhandle up
into southern MS/AL and for southern Louisiana. Ample moisture is
present with PW of 2.2" to 2.4" along the central Gulf Coast, so
isolated flash flood threats persist overnight with the Marginal
Risk still in affect.

Jackson

Day 2
Valid 12Z Wed Jul 22 2026 - 12Z Thu Jul 23 2026

...THERE IS A MODERATE RISK FOR EXCESSIVE RAINFALL OVER PORTIONS
THE TIDEWATER OF VIRGINIA AND NORTH CAROLINA...

...Carolinas, Southern Virginia, and Northern Georgia...

21Z update... Given the steady influx of tropical moisture from
T.S. Bertha northeastward into the sinking strong cold front,
widespread convection with embedded heavy rainfall will focus over
North Carolina and Virginia Tidewater region. There is a signal for
2 to 4 inches for this part of the country and rainfall rates could
easily exceed 1.5/2 inches per hour. Training/repeating of storms
expected along the frontal boundary therefore a Moderate Risk was
raised for this period.

Campbell

A strong cold front running into highly anomalous moisture being
siphoned from the circulation of Tropical Storm Bertha will
exacerbate the gradient of moisture along the frontal interface
through the day across the Carolinas and into southeastern
Virginia. This will work to keep any forward progress of the front
minimal. Storms will train along the front, especially across
northeastern North Carolina and into southeastern Virginia. This
area remains in a higher-end Slight Risk and with the stalled out
front remaining to guide the frequent development of additional
storms, a Moderate Risk upgrade in areas where the storms focused
in the Day 1 period remains a distinct possibility. Guidance has
been laser focused in this area and so forecast changes have been
minimal. Further south and west, however, guidance has become
increasingly optimistic on storms developing further west into the
southern Appalachians. As such, the Slight Risk was expanded west
to include this region from north of Atlanta through the western
Carolinas.

...Intermountain West...

21z update... Minor expansions of the Marginal Risk were made
across north-central Arizona and eastern Kansas to reflect the new
WPC QPF placement. The latest CAMs indicated a modest uptick in
convection for north-central and southeast Wyoming and northeast of
Boulder Colorado, which was just outside the inherited Slight Risk
area. Therefore eastward adjustments were made to the Slight Risk
area.

Campbell

Highly anomalous amounts of atmospheric moisture associated with
the monsoon over the Intermountain West will be activated by rapid
height falls as an upper level and highly negatively tilted trough
pushes east from off the coast of Washington and Oregon. Meanwhile,
separate upper level energy undercutting the ridge will also
provide additional forcing further east across eastern Idaho and
Wyoming. Once again, numerous thunderstorms will form in the
anomalous moisture and for many areas, will be tied to the local
topography. Few changes were needed with this update. The greatest
amounts of rain look to concentrate in western Wyoming, where any
storms south of Yellowstone could necessitate a higher-end Slight
for some of those areas, as well as for the Uintas of northern
Utah. With nearly all of the forcing further north, the Marginal
Risk into southern Arizona and southern New Mexico was trimmed
significantly with this update, as ridging quickly overtakes this
area and limits convective potential south/west of the Mogollon Rim
as a result.

...Tropical Storm Bertha/Gulf Coast...

Strengthening shear across the circulation will continue to keep
any organized convection and meaningful rainfall out over the open
waters of the Gulf. The immediate coastline could still see amounts
greater than an inch, but the rainfall footprint continues to shift
off the coast. In coordination with LIX/Slidell, LA forecast
office, the inherited Slight Risk for this region was downgraded
with this update, with the overall area of the surrounding Marginal
remaining little changed. What little rainfall does impact land
areas remains with the potential to be locally heavy, so
unfortunately no changes to the Marginal Risks can be made so long
as Bertha remains a tropical entity.

Wegman

Day 3
Valid 12Z Thu Jul 23 2026 - 12Z Fri Jul 24 2026

...THERE IS A MODERATE RISK FOR EXCESSIVE RAINFALL OVER PORTIONS
NORTH CAROLINA...

...Southeast...

21Z update... The heavy rainfall mentioned for the Day 2 period
will persist across North Carolina and surrounding locations as the
tropical moisture continues to interact with the stalled frontal
boundary. Training/repeating of storms will focus an additional 2
to 4+ inches over North Carolina and portions of southern/southeast
Virgina bringing the 48-hr forecast of 4 to 9+ inches for the
region. There will likely be a fair amount of overlap in the QPF
footprint from the D2 period, which will already be well saturated
prior to this period. A Moderate was also raised central and
east/northeast North Carolina as scattered to widespread instances
of flash flooding is expected.

Campbell

The stalled out front that has remained across the Southeast will
continue to plague the area with very heavy rainfall, as the
continuous stream of Gulf moisture from the Gulf funnels
northeastward along the front. Yet another day of heavy rain is
expected to impact the Carolinas as a result. The front may drift
ever so slightly further south and east which should clear all but
the Hampton Roads area of far southeast Virginia from the heavy
rainfall threat by Thursday, but for much of eastern North
Carolina, much of South Carolina, and portions of northern Georgia,
generally from Atlanta east, the heavy rainfall threat will
continue through Thursday. Once again, potential for very heavy
rainfall totals in many areas as are expected to see heavy rain
from Wednesday could mean further upgrades to the risks may be
needed, especially across eastern North Carolina. Ultimately, where
the heaviest rain falls both today and Wednesday should dictate if
further upgrades will be needed.

...Central Plains...

An MCS is expected to impact a portion of northeast Kansas,
southeast Nebraska and the Kansas City and St. Joseph metros on
Thursday. The heavy rainfall footprint has drifted south and west,
so the Slight Risk has been adjusted accordingly. As with many
MCS's the location of the heaviest rain is likely to continue
shifting with future updates, most likely towards the south, so
stay tuned for further updates. Periods of heavy rain may continue
to impact Wyoming into Colorado as well, where upgrades to a Slight
are also probable, depending on where the heavy rains from
Wednesday overlap with Thursday's forecast.

...Bertha...

21Z update... Rainfall trends across far southeast Texas have
trended down with the latest guidance thus the threat for isolated
flash flooding has reduced as well. The Marginal Risk was trimmed
out of Texas for this period.

Campbell

Bertha, who may no longer be a tropical cyclone by Thursday, and
likely to be in a weakening state, should continue to keep any
associated rainfall off the coast. The immediate coast remains with
the best chance for seeing anything over an inch of associated
rainfall. FFGs are significantly higher than that in all areas.
Given this, and with very good consistency in this scenario in the
guidance, the inherited Slight and Marginal for a portion of the
Texas and Louisiana Gulf coasts was removed with this update. The
Marginal Risk has been downgraded to under a 5% risk for the upper
Texas Gulf Coast, as well as the Slight for coastal Louisiana
downgraded to a Marginal with this update.

Wegman

Day 4 and Day 5

Valid 12Z Fri Jul 24 2026 - 12Z Sun Jul 26 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR MISSOURI ON
DAY 4 AND FOR PARTS OF THE CAROLINAS DAYS 4 AND 5...

...Southeast...
The multi-day rainfall event continues into the weekend, with
additional heavy rains likely, especially for the Carolinas. The
focus for these rains will be a slow-moving, moisture-laden front
that is forecast to linger across the region through at least the
first half of the weekend. Southwesterly flow ahead of a shortwave
trough moving through the Ohio/Tennessee valleys will further
fortify the already moisture- rich airmass, with models showing PWs
increasing in excess of 2.25 inches (+2 to 3 sigma). This
moisture, along with pockets of enhanced ascent afforded by mid-
level energy, will support periods of heavy, highly-efficient
rainfall. While areas of heavy rainfall are likely, forecast
confidence regarding their placement remains limited due to
continuing model spread with regards to the placement of the front,
which will have impacts on where the heaviest amounts occur. Slight
Risks are expanded west to include both central and eastern
sections of the Carolinas for both Days 4 and 5.

...Missouri to the Tennessee Valleys/Southern Appalachians...
There should be some ongoing activity over Missouri Friday morning
with greater confidence on a more vigorous setup over much of
Missouri after peak diurnal Friday afternoon/evening. PW increases
to 2-2.25 inches with support from southwesterly low level inflow
and potential frontal boundaries. The Day 4 Slight Risk was
expanded a bit over Missouri.

Farther south, frontal forcing will help focus diurnal convection
over northern AL/GA east into South Carolina with a Day 4 Marginal
Risk now connected from Missouri to the Carolinas along this
frontal boundary.

The Day 5 Marginal Risk was refocused to be along the continued
frontal boundary from southeast Missouri through the Tennessee
Valley instead of to the Gulf Coast. Given this larger change,
please be on the lookout for further refinement.

...Southwest/Great Basin/Central and Southern Rockies...
A downward trend in convective coverage and potential flash
flooding late is forecast for Friday with a Marginal Risk limited
to terrain around the Four Corners. Moisture anomalies then
increase again for Saturday which along with mid level energy
moving around the southwestern periphery of a broad high will help
expand afternoon and evening storm coverage. A broader Marginal is
in effect for Day 5, including the southern Arizona deserts and the
majority of the Four Corners states into eastern Nevada. WFOs ABQ
and EPZ were concerned about mid level warmth/capping when asked
about a Day 5 Slight for the Sangre de Cristo/Sacramento, so that
remains a Marginal at this time.

...Gulf Coast...
Confidence has increased on heavy rain associated with Bertha
remaining away from the Texas and Gulf Coasts on Friday to warrant
removal of the Day 4 Marginal from Texas. Further more, frontal
related rainfall both Friday and Saturday is now focused far enough
inland to not have A Marginal Risk on the coast for either day.

Jackson/Pereira

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!9iIoD2rxPHN9SVro3UuXoi1Yqar_i8Dv8rjohhxf7oHJukHcUnFCwNirVJOHjCfatVEFUuUGWwKLpSrQw-BrJJw6QDM$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!9iIoD2rxPHN9SVro3UuXoi1Yqar_i8Dv8rjohhxf7oHJukHcUnFCwNirVJOHjCfatVEFUuUGWwKLpSrQw-Br3JnLOaE$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!9iIoD2rxPHN9SVro3UuXoi1Yqar_i8Dv8rjohhxf7oHJukHcUnFCwNirVJOHjCfatVEFUuUGWwKLpSrQw-Br-XJwMhM$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Jul 22 08:26:42 2026

FOUS30 KWBC 220826
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
426 AM EDT Wed Jul 22 2026

Day 1
Valid 12Z Wed Jul 22 2026 - 12Z Thu Jul 23 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR SOUTHEASTERN
VIRGINIA AND EXTREME NORTHEASTERN NORTH CAROLINA...

...Southeast...

A strong but painfully slow moving cold front draped across
Virginia today will continue to act as a train track along which
numerous showers and thunderstorms will move throughout the day and
into tonight. It's probable that many areas from western North
Carolina through Raleigh and into the Hampton Roads area of
southeast Virginia will see more time over the next 24 hours seeing
moderate to heavy rainfall than dry time. The heaviest and most
persistent rainfall will be into extreme northeastern North
Carolina and much of southeastern Virginia southeast of Richmond
today. The Hampton Roads metro appears to be the most at risk of
the metro areas expected to be impacted by heavy rains today. It's
likely areal averages in the Hampton Roads area will exceed 3
inches today through tonight. Given both the persistence of the
heavy rain and urban concerns, the inherited Moderate Risk area
will remain unchanged with this update, generally following the
state line east from I-95 to the mouth of the Chesapeake.

Elsewhere the Slight Risk area extending from northern Georgia to
the Delmarva was shrunk both on the north and south sides with this
update. The CAMs guidance are in good agreement on the corridor
where heavy rain and flash flooding will be, increasing the
confidence that a smaller latitudinal range will be covered by the
heavy rain. As such, the southeastern corner of NC and all but
northern SC were removed from the risk categories as the heaviest
rains will stay north of those areas for today. They'll get their
turn in the coming days. The length of the front will promote heavy
rain development towards the west, and as such the Slight was
expanded west into northeastern Alabama with this update, where the
combination of the front and topography will both support areas of
heavy rain and widely scattered instances of flash flooding.

...Intermountain West...

The Slight Risk area covering an expansive area of the
Intermountain West from southwestern Montana south through
northwestern New Mexico was largely unchanged with this update.
However, in coordination with ABQ/Albuquerque, NM forecast office,
the Slight Risk area was expanded south along the AZ/NM state line
with this update. Plentiful burn scars, relatively little amounts
of rain it's taken in some areas to cause flash flooding, and many
areas not seeing recent flooding at all are all contributing
factors to the Slight Risk upgrade. Meanwhile further north, the
heaviest rainfall totals will be tied to the topography in many
areas from the Bitterroots through Yellowstone, much of Utah and
western Colorado. With sufficient upper level forcing helping the
storms to form and cause flash flooding, it's probable in many
instances that any storms that start along the topography will move
off the mountains towards the northeast, so lower elevation valleys
in between also remain in the Slight Risk for flooding.

...Gulf Coast/Tropical Storm Bertha...

T.S. Bertha will continue to struggle from strong northeasterly
shear pulling nearly all of the significant associated rainfall
south over the open waters of the Gulf. With little rain expected
along the Gulf Coast, the inherited Marginal remains little
changed. The Marginal mostly covers the fact that any significant
tropical cyclone carries inordinate amounts of atmospheric
moisture, even when being sheared. That moisture can easily support
heavy rainfall, even if isolated, so the Marginal threat remains.

Wegman

Day 2
Valid 12Z Thu Jul 23 2026 - 12Z Fri Jul 24 2026

...THERE'S A MODERATE RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
EASTERN NORTH CAROLINA...

...Southeast...

A strong and very slow moving cold front draped across portions of
the Mid-Atlantic on Wednesday makes only very slow progress through
the day Thursday across far southern Virginia and northwestern
North Carolina. A second day of intense rainfall in the form of
seemingly endless trains of storms will impact much of the
Carolinas on Thursday. The good news is the southward progress of
the front on the order of about 50 miles or so will spare most of
Virginia much heavy rainfall for yet another day. However, this
means the heavy rain simply impacts areas further south across much
of North Carolina and northern South Carolina. Unfortunately there
looks to be some overlap in the heavy rainfall footprints from
Wednesday into Thursday, particularly in northeastern North
Carolina, likely extending from Norfolk south and east. Once again
the heaviest rainfall amounts will likely concentrate along the
coast. As such the Moderate Risk for this period was also
unchanged, focused from I-95 east and from I-40 north and east.

Further west, a similar situation remains as on Wednesday.
Painfully slow southward movement means many of the same areas get
hit with heavy rains again on Thursday as on Wednesday. The Slight
Risk was expanded west along the front due to the large amounts of
atmospheric moisture in place immediately ahead of the front. Many
areas have PWATs above 2 inches. The Slight Risk area includes
metros Birmingham, AL, Atlanta, and into Charlotte, NC. All 3 of
these metros have some risk of training storms, with Charlotte the
highest of those 3.

...Central Plains...

A pair of nocturnal MCSs, one Wednesday night into Thursday
morning, and a second much stronger one Thursday night into Friday,
will impact portions of southeastern Nebraska, northeastern Kansas,
and into small portions of Iowa and Missouri through the period.
These back-to-back MCSs will sufficiently soak the soils such that
the heavy rain with Thursday Night's MCS will cause widely
scattered instances of flash flooding, especially where urban areas
such as Lincoln, Topeka, St. Joseph, and possibly Omaha and Kansas
City are impacted. The area of the Slight was adjusted, but remains
little changed with this update. The isolated flash flooding threat
represented by the Marginal extends well west of there through
nearly all of Wyoming and Colorado. While the flooding threat
diminishes considerably in these states compared with Wednesday,
the leftover saturated soils and still likely formation of showers
and storms will keep an isolated flash flooding threat going.

...Bertha/South Texas...

Latest CAMs guidance are starting to come into agreement on a
solution that keeps the circulation of Bertha intact over the
northwestern Gulf before the westward moving storm moves inland in
Texas near or south of Houston. As such, the persistent convection
that continues to focus south/southwest of the center eventually
impacts land areas, in this case in south Texas. A Marginal Risk
covering much of South Texas was introduced with this update. It's
likely that a Slight Risk upgrade will be needed with future
updates, short of a northward jog in the guidance that kills off
the rain much earlier, as the guidance had been showing in recent
days. The area most likely to see that upgrade is around Corpus
Christi through Victoria.

Wegman

Day 3
Valid 12Z Fri Jul 24 2026 - 12Z Sat Jul 25 2026

..THERE ARE SLIGHT RISKS OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHEAST AS WELL AS FOR MUCH OF MISSOURI...

...Southeast...

The front that has been causing heavy rain across portions of the
Southeast through Thursday continues on into Friday, though begins
to weaken and in some areas lift back to the north as a warm front.
Due to this weakening forcing, the rainfall forecast footprint over
the Carolinas diminishes substantially (by about half) as compared
with prior days' rains. While many areas continue to see periods of
heavy rain, which may overlap with heavy rainfall from prior days,
the much lower rainfall forecast over North Carolina did allow for
the risk level to drop back into the Slight category for the Friday
period. That said, any increase in rainfall, especially for areas
hit hard on Wednesday and Thursday, could easily necessitate
another upgrade to a Moderate for portions of eastern North
Carolina with future updates.

The rainfall forecast increases from prior days further west into
northern Alabama and Georgia. The inherited Slight risk, as on past
days, was expanded west. In this case, the expansion went all the
way to the Mississippi state line with Alabama, as Alabama in
particular looks to have its wettest day of the week on Friday.
Considering prior days rains forecast for this same area, more
favorable hydrology and further increases in expected rainfall in
northern Alabama and Georgia could mean a Moderate Risk upgrade
with future updates isn't entirely out of the question. Certainly
eastern NC has a much higher chance of this happening.

...Missouri...

An MCS over the area Friday morning diminishes in intensity with
differential heating over the Plains and Ozarks on Friday. However,
guidance is not in good agreement as to whether or not the rainfall
dissipates entirely. Peak heating could provide enough instability
that the convective organization changes, but not its coverage.
Thus, A Slight Risk for a large portion of Missouri remains in
place. Any rain will continue in this area into Friday night.

...Texas..

Regardless of whether Bertha does better at maintaining its
intensity on Thursday, or if it dies earlier by taking a more
northerly track, by Friday the rainfall associated with the storm
will be long dissipated or diminished to nuisance showers. As
such, all flooding risks directly associated with Bertha will be
ended by Friday.

Wegman

Day 4 and Day 5

Valid 12Z Sat Jul 25 2026 - 12Z Mon Jul 27 2026

...THERE IS A MARGINAL RISK FOR EXCESSIVE RAINFALL FROM THE MID
MISSISSIPPI VALLEY TO THE SOUTHEAST DAY 4 AND ACROSS PORTIONS OF
THE WESTERN U.S. DAYS 4 AND 5...

...Mid Mississippi Valley to the Southeast...
The overall trend in the overnight guidance was to shift the slow-
moving surface front and associated axis of deeper moisture farther
east and off of the Southeast Coast on Saturday, diminishing the
threat for widespread additional heavy rains across the Carolinas.
Therefore, the Slight Risk was removed from the eastern Carolinas.
However, cannot rule out an isolated threat for localized heavy
rains and an isolated flash flood threat. Therefore, the Marginal
Risk was maintained for the Day 4 period from eastern North
Carolina into the Southeast before notably drier air begins to
spread across much of the region on Sunday.

The Marginal Risk was also maintained farther northwest back across
the Tennessee Valley into the mid Mississippi Valley. Some models,
more notably the ECMWF and UKMET, show elevated storms that are
expected to develop Friday night continuing to propagate southeast
from the mid Mississippi into the Mid South, with deepening
moisture and training storms raising the potential for heavy
accumulations. As the associated mid level energy continues to drop
southeast, there is the potential for at least locally heavy
amounts and isolated flash flooding concerns as it interacts with
lingering deep moisture from the Tennessee Valley into Alabama and
Georgia on Saturday.

...Southwest to the northern Rockies...
After a dropoff late in the week, the footprint for diurnal
showers and storms is expected to expand once again by Saturday as
high moisture anomalies (+2 sigma) return to parts of Arizona and
New Mexico. This moisture along with mid-level energy moving
around the southern periphery of the high will raise the threat for efficient-rainfall producers, raising flash flooding concerns
across parts of the Southwest both days. This elevated moisture and
enhanced forcing may support the need for an upgrade to a Slight
Risk in future updates.

Meanwhile deeper moisture and energy lifting along the northwest
side of the high will extend the threat into parts of the northern Intermountain West and Rockies on Day 4, before moisture anomalies
drop off on Day 5.

Pereira

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!6D1knj56v415mhsonB65gQIepUFxa-KKipDX36j00curW6dbL3lONwTwZ1Vi429vAtRpwPsykCyOicP6wpomPr-RyDc$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!6D1knj56v415mhsonB65gQIepUFxa-KKipDX36j00curW6dbL3lONwTwZ1Vi429vAtRpwPsykCyOicP6wpomjXLk-dE$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!6D1knj56v415mhsonB65gQIepUFxa-KKipDX36j00curW6dbL3lONwTwZ1Vi429vAtRpwPsykCyOicP6wpomWE7EAuE$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Jul 22 15:56:06 2026

FOUS30 KWBC 221555
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1155 AM EDT Wed Jul 22 2026

Day 1
Valid 16Z Wed Jul 22 2026 - 12Z Thu Jul 23 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR SOUTHEASTERN
VIRGINIA AND EXTREME NORTHEASTERN NORTH CAROLINA...

...Southeast...

16Z UPDATE: No major changes were made to the outlook with this
update, other than small tweaks to account for the latest
observational trends and new 12Z hi-res model runs. A slow-moving
front will continue to act as a focus for training convective rain
bands and thunderstorms from the Upper Tennessee Valley into North
Carolina, southeast Virginia, and the far southern Delmarva
Peninsula. Although hi-res guidance now indicates less persistence
and focus to the convective activity overnight, with somewhat lower
rain threshold and FFG exceedance probabilities, the Moderate Risk
was maintained for continuity and a favorable pattern for training
convection. Within the Moderate Risk area, signals remain strongest
in the Hampton Roads area.

Meanwhile, the level of concern is increasing for later tonight for
the southern Appalachians, in particular the mountainous areas of
eastern Tennessee and western North Carolina, and perhaps far
northern Georgia. Deep moisture is expected to increase over the
next 12 hours as a more direct connection is made with some of the
low-mid level moisture associated with Bertha along the Gulf Coast.
This can be seen in the CIRA layer precipitable water products from
the Surface to 850mb, as well as 850-700mb. There has already been
a concerted northward push of anomalous moisture, and the PWAT at
BMX increased from 1.86 inches to 2.10 inches between the 06 UTC
and 12 UTC balloon launches. As this reaches the stalling front
tonight, with increasing westerly low-level flow parallel to that
front, ingredients will become favorable for reinvigoration of a
training and backbuilding convective band in the vicinity of the
southern Appalachians. QPF signals in the hi-res models have
increased, with some chances of rain rates reaching 2 inches per
hour if organized thunderstorms can become established. Therefore,
although the risk level is being held at Slight, this area will be
monitored closely in case a targeted upgrade is needed.

...Intermountain West...

16Z UPDATE: The risk areas were not changed appreciably with this
update. Within the Slight Risk area, there may be a greater
concentration of convection and flash flood potential in portions
of western Colorado, northeast Utah, and southern Wyoming. A well-
defined mid-upper level vorticity maximum is pushing into southeast
Utah, evident on GOES-West water vapor channels. To the north and
northeast of this feature, an area of enhanced upper level
divergence would be favored. This also overlaps with an area of
weak winds (and thus slow storm motions), moderate instability, and
anomalously high moisture, even for July. Given there is much less
cloud debris in these areas to restrict destabilization, the chance
of flash flooding may be considered to be at the higher end of the
Slight Risk range.

PREVIOUS DISCUSSION: In coordination with the Albuquerque forecast
office, the Slight Risk area was expanded south along the AZ/NM
state line. Plentiful burn scars, relatively little amounts of
rain it's taken in some areas to cause flash flooding, and many
areas not seeing recent flooding at all are all contributing
factors to the Slight Risk upgrade. Meanwhile further north, the
heaviest rainfall totals will be tied to the topography in many
areas from the Bitterroots through Yellowstone, much of Utah and
western Colorado. With sufficient upper level forcing helping the
storms to form and cause flash flooding, it's probable in many
instances that any storms that start along the topography will move
off the mountains towards the northeast, so lower elevation
valleys in between also remain in the Slight Risk for flooding.

...Gulf Coast/Tropical Storm Bertha...

PREVIOUS DISCUSSION: T.S. Bertha will continue to struggle from
strong northeasterly shear pulling nearly all of the significant
associated rainfall south over the open waters of the Gulf. With
little rain expected along the Gulf Coast, the inherited Marginal
remains little changed. The Marginal mostly covers the fact that
any significant tropical cyclone carries inordinate amounts of
atmospheric moisture, even when being sheared. That moisture can
easily support heavy rainfall, even if isolated, so the Marginal
threat remains.

Lamers/Wegman

Day 2
Valid 12Z Thu Jul 23 2026 - 12Z Fri Jul 24 2026

...THERE'S A MODERATE RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
EASTERN NORTH CAROLINA...

...Southeast...

A strong and very slow moving cold front draped across portions of
the Mid-Atlantic on Wednesday makes only very slow progress through
the day Thursday across far southern Virginia and northwestern
North Carolina. A second day of intense rainfall in the form of
seemingly endless trains of storms will impact much of the
Carolinas on Thursday. The good news is the southward progress of
the front on the order of about 50 miles or so will spare most of
Virginia much heavy rainfall for yet another day. However, this
means the heavy rain simply impacts areas further south across much
of North Carolina and northern South Carolina. Unfortunately there
looks to be some overlap in the heavy rainfall footprints from
Wednesday into Thursday, particularly in northeastern North
Carolina, likely extending from Norfolk south and east. Once again
the heaviest rainfall amounts will likely concentrate along the
coast. As such the Moderate Risk for this period was also
unchanged, focused from I-95 east and from I-40 north and east.

Further west, a similar situation remains as on Wednesday.
Painfully slow southward movement means many of the same areas get
hit with heavy rains again on Thursday as on Wednesday. The Slight
Risk was expanded west along the front due to the large amounts of
atmospheric moisture in place immediately ahead of the front. Many
areas have PWATs above 2 inches. The Slight Risk area includes
metros Birmingham, AL, Atlanta, and into Charlotte, NC. All 3 of
these metros have some risk of training storms, with Charlotte the
highest of those 3.

...Central Plains...

A pair of nocturnal MCSs, one Wednesday night into Thursday
morning, and a second much stronger one Thursday night into Friday,
will impact portions of southeastern Nebraska, northeastern Kansas,
and into small portions of Iowa and Missouri through the period.
These back-to-back MCSs will sufficiently soak the soils such that
the heavy rain with Thursday Night's MCS will cause widely
scattered instances of flash flooding, especially where urban areas
such as Lincoln, Topeka, St. Joseph, and possibly Omaha and Kansas
City are impacted. The area of the Slight was adjusted, but remains
little changed with this update. The isolated flash flooding threat
represented by the Marginal extends well west of there through
nearly all of Wyoming and Colorado. While the flooding threat
diminishes considerably in these states compared with Wednesday,
the leftover saturated soils and still likely formation of showers
and storms will keep an isolated flash flooding threat going.

...Bertha/South Texas...

Latest CAMs guidance are starting to come into agreement on a
solution that keeps the circulation of Bertha intact over the
northwestern Gulf before the westward moving storm moves inland in
Texas near or south of Houston. As such, the persistent convection
that continues to focus south/southwest of the center eventually
impacts land areas, in this case in south Texas. A Marginal Risk
covering much of South Texas was introduced with this update. It's
likely that a Slight Risk upgrade will be needed with future
updates, short of a northward jog in the guidance that kills off
the rain much earlier, as the guidance had been showing in recent
days. The area most likely to see that upgrade is around Corpus
Christi through Victoria.

Wegman

Day 3
Valid 12Z Fri Jul 24 2026 - 12Z Sat Jul 25 2026

..THERE ARE SLIGHT RISKS OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHEAST AS WELL AS FOR MUCH OF MISSOURI...

...Southeast...

The front that has been causing heavy rain across portions of the
Southeast through Thursday continues on into Friday, though begins
to weaken and in some areas lift back to the north as a warm front.
Due to this weakening forcing, the rainfall forecast footprint over
the Carolinas diminishes substantially (by about half) as compared
with prior days' rains. While many areas continue to see periods of
heavy rain, which may overlap with heavy rainfall from prior days,
the much lower rainfall forecast over North Carolina did allow for
the risk level to drop back into the Slight category for the Friday
period. That said, any increase in rainfall, especially for areas
hit hard on Wednesday and Thursday, could easily necessitate
another upgrade to a Moderate for portions of eastern North
Carolina with future updates.

The rainfall forecast increases from prior days further west into
northern Alabama and Georgia. The inherited Slight risk, as on past
days, was expanded west. In this case, the expansion went all the
way to the Mississippi state line with Alabama, as Alabama in
particular looks to have its wettest day of the week on Friday.
Considering prior days rains forecast for this same area, more
favorable hydrology and further increases in expected rainfall in
northern Alabama and Georgia could mean a Moderate Risk upgrade
with future updates isn't entirely out of the question. Certainly
eastern NC has a much higher chance of this happening.

...Missouri...

An MCS over the area Friday morning diminishes in intensity with
differential heating over the Plains and Ozarks on Friday. However,
guidance is not in good agreement as to whether or not the rainfall
dissipates entirely. Peak heating could provide enough instability
that the convective organization changes, but not its coverage.
Thus, A Slight Risk for a large portion of Missouri remains in
place. Any rain will continue in this area into Friday night.

...Texas..

Regardless of whether Bertha does better at maintaining its
intensity on Thursday, or if it dies earlier by taking a more
northerly track, by Friday the rainfall associated with the storm
will be long dissipated or diminished to nuisance showers. As
such, all flooding risks directly associated with Bertha will be
ended by Friday.

Wegman

Day 4 and Day 5

Valid 12Z Sat Jul 25 2026 - 12Z Mon Jul 27 2026

...THERE IS A MARGINAL RISK FOR EXCESSIVE RAINFALL FROM THE MID
MISSISSIPPI VALLEY TO THE SOUTHEAST DAY 4 AND ACROSS PORTIONS OF
THE WESTERN U.S. DAYS 4 AND 5...

...Mid Mississippi Valley to the Southeast...
The overall trend in the overnight guidance was to shift the slow-
moving surface front and associated axis of deeper moisture farther
east and off of the Southeast Coast on Saturday, diminishing the
threat for widespread additional heavy rains across the Carolinas.
Therefore, the Slight Risk was removed from the eastern Carolinas.
However, cannot rule out an isolated threat for localized heavy
rains and an isolated flash flood threat. Therefore, the Marginal
Risk was maintained for the Day 4 period from eastern North
Carolina into the Southeast before notably drier air begins to
spread across much of the region on Sunday.

The Marginal Risk was also maintained farther northwest back across
the Tennessee Valley into the mid Mississippi Valley. Some models,
more notably the ECMWF and UKMET, show elevated storms that are
expected to develop Friday night continuing to propagate southeast
from the mid Mississippi into the Mid South, with deepening
moisture and training storms raising the potential for heavy
accumulations. As the associated mid level energy continues to drop
southeast, there is the potential for at least locally heavy
amounts and isolated flash flooding concerns as it interacts with
lingering deep moisture from the Tennessee Valley into Alabama and
Georgia on Saturday.

...Southwest to the northern Rockies...
After a dropoff late in the week, the footprint for diurnal
showers and storms is expected to expand once again by Saturday as
high moisture anomalies (+2 sigma) return to parts of Arizona and
New Mexico. This moisture along with mid-level energy moving
around the southern periphery of the high will raise the threat for efficient-rainfall producers, raising flash flooding concerns
across parts of the Southwest both days. This elevated moisture and
enhanced forcing may support the need for an upgrade to a Slight
Risk in future updates.

Meanwhile deeper moisture and energy lifting along the northwest
side of the high will extend the threat into parts of the northern Intermountain West and Rockies on Day 4, before moisture anomalies
drop off on Day 5.

Pereira

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!8KEivmKUFJlgdc5mDjph7sN4EuEdQk57bjJMlrdNXtf1pL657kKBZeGIqCKyMXVbhwpP0ZISp5t3M0LziM_aGUPa-s0$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!8KEivmKUFJlgdc5mDjph7sN4EuEdQk57bjJMlrdNXtf1pL657kKBZeGIqCKyMXVbhwpP0ZISp5t3M0LziM_aMtbGjQU$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!8KEivmKUFJlgdc5mDjph7sN4EuEdQk57bjJMlrdNXtf1pL657kKBZeGIqCKyMXVbhwpP0ZISp5t3M0LziM_aTEpeBWs$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Wed Jul 22 20:08:10 2026

FOUS30 KWBC 222007
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
407 PM EDT Wed Jul 22 2026

Day 1
Valid 16Z Wed Jul 22 2026 - 12Z Thu Jul 23 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR SOUTHEASTERN
VIRGINIA AND EXTREME NORTHEASTERN NORTH CAROLINA...

...Southeast...

16Z UPDATE: No major changes were made to the outlook with this
update, other than small tweaks to account for the latest
observational trends and new 12Z hi-res model runs. A slow-moving
front will continue to act as a focus for training convective rain
bands and thunderstorms from the Upper Tennessee Valley into North
Carolina, southeast Virginia, and the far southern Delmarva
Peninsula. Although hi-res guidance now indicates less persistence
and focus to the convective activity overnight, with somewhat lower
rain threshold and FFG exceedance probabilities, the Moderate Risk
was maintained for continuity and a favorable pattern for training
convection. Within the Moderate Risk area, signals remain strongest
in the Hampton Roads area.

Meanwhile, the level of concern is increasing for later tonight for
the southern Appalachians, in particular the mountainous areas of
eastern Tennessee and western North Carolina, and perhaps far
northern Georgia. Deep moisture is expected to increase over the
next 12 hours as a more direct connection is made with some of the
low-mid level moisture associated with Bertha along the Gulf Coast.
This can be seen in the CIRA layer precipitable water products from
the Surface to 850mb, as well as 850-700mb. There has already been
a concerted northward push of anomalous moisture, and the PWAT at
BMX increased from 1.86 inches to 2.10 inches between the 06 UTC
and 12 UTC balloon launches. As this reaches the stalling front
tonight, with increasing westerly low-level flow parallel to that
front, ingredients will become favorable for reinvigoration of a
training and backbuilding convective band in the vicinity of the
southern Appalachians. QPF signals in the hi-res models have
increased, with some chances of rain rates reaching 2 inches per
hour if organized thunderstorms can become established. Therefore,
although the risk level is being held at Slight, this area will be
monitored closely in case a targeted upgrade is needed.

...Intermountain West...

16Z UPDATE: The risk areas were not changed appreciably with this
update. Within the Slight Risk area, there may be a greater
concentration of convection and flash flood potential in portions
of western Colorado, northeast Utah, and southern Wyoming. A well-
defined mid-upper level vorticity maximum is pushing into southeast
Utah, evident on GOES-West water vapor channels. To the north and
northeast of this feature, an area of enhanced upper level
divergence would be favored. This also overlaps with an area of
weak winds (and thus slow storm motions), moderate instability, and
anomalously high moisture, even for July. Given there is much less
cloud debris in these areas to restrict destabilization, the chance
of flash flooding may be considered to be at the higher end of the
Slight Risk range.

PREVIOUS DISCUSSION: In coordination with the Albuquerque forecast
office, the Slight Risk area was expanded south along the AZ/NM
state line. Plentiful burn scars, relatively little amounts of
rain it's taken in some areas to cause flash flooding, and many
areas not seeing recent flooding at all are all contributing
factors to the Slight Risk upgrade. Meanwhile further north, the
heaviest rainfall totals will be tied to the topography in many
areas from the Bitterroots through Yellowstone, much of Utah and
western Colorado. With sufficient upper level forcing helping the
storms to form and cause flash flooding, it's probable in many
instances that any storms that start along the topography will move
off the mountains towards the northeast, so lower elevation
valleys in between also remain in the Slight Risk for flooding.

...Gulf Coast/Tropical Storm Bertha...

PREVIOUS DISCUSSION: T.S. Bertha will continue to struggle from
strong northeasterly shear pulling nearly all of the significant
associated rainfall south over the open waters of the Gulf. With
little rain expected along the Gulf Coast, the inherited Marginal
remains little changed. The Marginal mostly covers the fact that
any significant tropical cyclone carries inordinate amounts of
atmospheric moisture, even when being sheared. That moisture can
easily support heavy rainfall, even if isolated, so the Marginal
threat remains.

Lamers/Wegman

Day 2
Valid 12Z Thu Jul 23 2026 - 12Z Fri Jul 24 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
FAR SOUTHEAST VIRGINIA AND EASTERN NORTH CAROLINA...

...Southeast...

Convection may be ongoing at the start of the period along or just
south of a slow-moving cold front. Hi-res guidance has slowed the
southward progression slightly relative to previous model cycles,
and the main change with the outlook was to pull the risk contours
north to account for where there may be active flash flooding
around 12Z Thursday. This is most likely from far northeast North
Carolina into the Hampton Roads area of southeast Virginia, as well
as the southern Appalachians from southeast Tennessee into
southwest North Carolina, and perhaps far northern Georgia. Low-mid
level flow parallel to the front, with PWATs over 2 inches, should
be conducive to backbuilding and training, and the potential for
narrow corridors with persistent hourly rain rates reaching 2
inches per hour.

As diurnal heating commences, and especially toward the 18-00Z
period, convection is likely to refocus a bit further south where
more instability will be building, and perhaps along outflow
boundaries that will push away from the synoptic front. This would
likely shift the flash flooding threat into the remainder of the
Carolinas, north Georgia, and northern Alabama for the remainder of
the period, especially during the afternoon and evening. PWATs will
generally be around or just over 2 inches, and should continue to
support high rain rates at least approaching 2 inches per hour at
times. This should lead to scattered instances of flash flooding,
and could include some of the larger urban areas in the Southeast.

...Eastern Colorado...

A Slight Risk was introduced in Eastern Colorado, as there is
emerging signal in guidance for an area of more concentrated
convection on Thursday afternoon and evening. HREF and REFS
probabilities of rain rates over 1 inch per hour increase to around
30-50 percent between 20Z and 04Z, and probabilities of exceeding
1hr FFG are around 10-20 percent. Precipitable water values above
the 95th pecentile for July would be conducive to those higher rain
rates in areas where instablity builds. Although convection is
likely to steadily progress to the east, rain rates are likely to
be high enough to pose a risk for some flash flooding.

...Central Plains...

Multiple MCSs will develop across the Central Plains over the next
40 hours -- one late tonight (Day 1 period) into Thursday morning
(beginning of the Day 2 period), and another one Thursday Night
into Friday (late in the Day 2 period into the Day 3 period). EAS
probabilities from the HREF and REFS show much better agreement
that the first MCS is most likely from south-central Nebraska into
east-central Kansas, and this is where the Slight Risk was
maintained. For the second MCS, EAS probabilities are lower,
indicating lower confidence and more spread on placement.
Therefore, it's not certain that the rainfall footprints of both
will overlap to a considerable degree; if that does happen, it
would make flash flooding more likely. However, rain rates in the
first MCS may be sufficiently high (1-2 inches per hour) to pose a
flash flooding threat on its own.

...Bertha/South Texas...

Models continue to show a coherent signal for heavy rainfall
through South Texas, related to a convective cluster well displaced
from Bertha's center. A Slight Risk upgrade was considered given
the deep tropical moisture that is likely to be present, however
this is also mitigated by extremely dry antecedent conditions
(rainfall less than 25 percent of normal in the past month). FFG in
South Texas is among the highest in the country at the moment.
Finally, all models show a steady westward progression of the
convection, such that it doesn't linger in any one spot for more
than a few hours. Considering that, and in collaboration with WFOs
in Corpus Christi and Brownsville, the risk level was held at a
Marginal Risk for now.

Lamers

Day 3
Valid 12Z Fri Jul 24 2026 - 12Z Sat Jul 25 2026

..THERE ARE SLIGHT RISKS OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHEAST AS WELL AS FOR MUCH OF MISSOURI...

...Southeast...

The continued presence of the stalled front in the Southeast should
continue to focus additional rounds of convection on Friday,
although given the lead time the placement is more uncertain. While
the front itself may become more diffuse, this may be counteracted
by decreasing deep layer mean flow as an upper level ridge axis
builds in (potential for slower storm motions) and increasing
precipitable water. Models actually show a much larger area of
PWATs in excess of 2 inches than prior days, and combined with
relatively strong instability, the environment would be very
supportive of intense rain rates exceeding 2 inches per hour at
times. If these more intense rain rates intersect (and persist)
over areas that received heavy rain in prior days, or some of the
major urban centers in the Southeast, then some locally significant
flash flooding could result. Portions of the region will be
monitored for a potential upgrade to Moderate Risk. Right now that
seems most likely from north-central Alabama into north Georgia,
and the eastern Carolinas, but it's important to stay tuned for
future updates as a lot will likely depend on convective evolution
over the next two days.

...Eastern Kansas and Missouri...

The Slight Risk was maintained and is still centered on much of
Missouri. This will be a continuation of convective activity from
the Day 2 period. It should be noted there is considerable spread
in the position of a potential MCS among available reliable
guidance members. For example, the 12Z ECMWF has the rainfall
maximum centered in northeast Missouri, to the north of St. Louis.
Meanwhile, the 12Z AI-GFS and RRFS are as far away as southeast
Kansas, a displacement of around 200 miles. These different model
scenarios depict dry or nearly dry conditions where the other has a
corridor of very heavy rain. This obviously has implications for
narrowing down the risk area. For now the Slight Risk was kept
fairly broad to account for model spread, and a large area with at
least a 15 percent chance of flash flooding as a result. This may
get narrowed with time.

Lamers

Day 4 and Day 5

Valid 12Z Sat Jul 25 2026 - 12Z Mon Jul 27 2026

...THERE IS A MARGINAL RISK FOR EXCESSIVE RAINFALL FROM THE MID
MISSISSIPPI VALLEY THROUGH THE CAROLINAS DAY 4, A PORTION OF THE
UPPER MIDWEST ON DAY 5, AND ACROSS PORTIONS OF THE WESTERN U.S.
DAYS 4 AND 5...

...Mid Mississippi Valley to the Southeast...
The trend with Carolina Coast QPF on Saturday went slower meaning
more rain along the Coast. It seems fine to continue with just a
Marginal Risk for Day 4, though that was expanded back inland a
bit to encompass all of eastern NC. Given the high amounts of
rainfall forecast over eastern NC over the next few days, any
further trend inland would warrant a reintroduction of a Slight
Risk.

Widened the Day 4 Marginal Risk over southeast Missouri given some
uncertainty on the frontal placement there. The 12Z RRFS is also
farther west over south-central MO Saturday afternoon. Otherwise,
the expectation is still for elevated storms to then propagate
southeast through the Mid South/TN Valley with deepening moisture
and training activity likely. Additional activity further
downstream along the front is likely over northern AL/much of GA
where the Marginal Risk remains.

...Southwest to the northern Rockies...
Monsoonal flow through the Intermountain West continues this
weekend. EC/GFS PW anomalies are lacking over AZ for Saturday, but
elevated over NM/CO/UT into WY. Moisture is more anomalous over all
these states on Sunday. The Day 4/5 Marginal Risks are similarly
drawn for both days with less coverage in northern AZ maintained
for Day 4. Furthermore, the Sacramento Mtns of NM were added to Day
5 given model QPF there along with some added moisture.

...Great Lakes...
Decent agreement among guidance for anomalously high moisture
shift to shift east from the northern Plains through the Upper
Midwest on Sunday on the top side of the upper high centered over
the TX Panhandle. This is a northwest flow scenario and where it
parallels any boundaries, repeating convection should occur. As of
now the heavy rain threat area seems centered on Wisconsin per
recent EC-AIFS and PW anomaly positioning from the EC/GFS. The
placement should be refined with time, but the presence of
repeating heavy thunderstorms has enough confidence to raise a Day
5 Marginal over Wisconsin into the LP of Michigan.

Jackson/Pereira

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!7WW4BiYZ2MiULA-9YAe6t1InKqeollMv_Jt4M5eS5s94CEfzhTTij_H6HmFJE7AaMQdIzJc2ytJBG-sGJO_pAsVbulk$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!7WW4BiYZ2MiULA-9YAe6t1InKqeollMv_Jt4M5eS5s94CEfzhTTij_H6HmFJE7AaMQdIzJc2ytJBG-sGJO_pzYCVlRQ$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!7WW4BiYZ2MiULA-9YAe6t1InKqeollMv_Jt4M5eS5s94CEfzhTTij_H6HmFJE7AaMQdIzJc2ytJBG-sGJO_pdqv9lGw$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Jul 23 00:38:40 2026

FOUS30 KWBC 230038
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
838 PM EDT Wed Jul 22 2026

Day 1
Valid 01Z Thu Jul 23 2026 - 12Z Thu Jul 23 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR SOUTHEASTERN
VIRGINIA INTO NORTH-CENTRAL NORTH CAROLINA...

...Southeast...

In spite of little rain thus far over Hampton Roads, the Moderate
Risk is maintained given the combination of ample moisture (PW
around 2") and elevated instability ahead of the slow moving cold
front. The heaviest activity in the southern Mid-Atlantic has been
farther north near the cold front over southern Maryland and in a
corridor over far south-central VA and back over the southern
Appalachians. The main threat for heavy rain in Hampton Roads is
after midnight.

A considerable flash flood threat remains for eastern Tennessee
through northern North Carolina overnight. This is from flow
parallel to the front drifting south allowing for repeating
activity. A slug of 2" PW is across west-central NC along with some
elevated MLCAPE of 2000 J/kg currently over western NC. This
corridor is considered to be in a higher end (or "enhanced") Slight
Risk overnight.

...Intermountain West onto the Central Plains...

The well-defined mid-upper level vorticity max is lifting up the
northern UT/CO border and will lift into WY overnight. The
Intermountain West activity has generally peaked with further
activity this evening focused over western WY and western CO into
northwest NM.

East of the Front Range are propagating multi-cell clusters feeding
on strong southeasterly flow of Gulf enriched moisture streaming up
the Great Plains. Expanded the Slight Risk over northeast CO and
southeast WY where FFG is a little lower and ongoing activity
should track (based on extrapolation and recent HRRR runs).
Overnight activity over central Nebraska tracking southeast into
northeastern Kansas is still expected as well (generally after
08Z).

...Gulf Coast/Tropical Storm Bertha...

Center of Bertha has tracked south of New Orleans. The main threats
are now ahead of the low center. Light scattered banding will
continue behind the system over the central Gulf Coast overnight,
but this does not warrant a Marginal Risk anymore, so that is
pulled. The Upper and Middle Texas are ahead of the low and banding
there is more potent, so a Marginal Risk is raised for the
overnight around and and south of Galveston Bay where PW is
currently peaking around 2.8". Heavy activity and isolated flash
flooding are the main rainfall threats for overnight.

Jackson

Day 2
Valid 12Z Thu Jul 23 2026 - 12Z Fri Jul 24 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
FAR SOUTHEAST VIRGINIA AND EASTERN NORTH CAROLINA...

...Southeast...

Convection may be ongoing at the start of the period along or just
south of a slow-moving cold front. Hi-res guidance has slowed the
southward progression slightly relative to previous model cycles,
and the main change with the outlook was to pull the risk contours
north to account for where there may be active flash flooding
around 12Z Thursday. This is most likely from far northeast North
Carolina into the Hampton Roads area of southeast Virginia, as well
as the southern Appalachians from southeast Tennessee into
southwest North Carolina, and perhaps far northern Georgia. Low-mid
level flow parallel to the front, with PWATs over 2 inches, should
be conducive to backbuilding and training, and the potential for
narrow corridors with persistent hourly rain rates reaching 2
inches per hour.

As diurnal heating commences, and especially toward the 18-00Z
period, convection is likely to refocus a bit further south where
more instability will be building, and perhaps along outflow
boundaries that will push away from the synoptic front. This would
likely shift the flash flooding threat into the remainder of the
Carolinas, north Georgia, and northern Alabama for the remainder of
the period, especially during the afternoon and evening. PWATs will
generally be around or just over 2 inches, and should continue to
support high rain rates at least approaching 2 inches per hour at
times. This should lead to scattered instances of flash flooding,
and could include some of the larger urban areas in the Southeast.

...Eastern Colorado...

A Slight Risk was introduced in Eastern Colorado, as there is
emerging signal in guidance for an area of more concentrated
convection on Thursday afternoon and evening. HREF and REFS
probabilities of rain rates over 1 inch per hour increase to around
30-50 percent between 20Z and 04Z, and probabilities of exceeding
1hr FFG are around 10-20 percent. Precipitable water values above
the 95th pecentile for July would be conducive to those higher rain
rates in areas where instablity builds. Although convection is
likely to steadily progress to the east, rain rates are likely to
be high enough to pose a risk for some flash flooding.

...Central Plains...

Multiple MCSs will develop across the Central Plains over the next
40 hours -- one late tonight (Day 1 period) into Thursday morning
(beginning of the Day 2 period), and another one Thursday Night
into Friday (late in the Day 2 period into the Day 3 period). EAS
probabilities from the HREF and REFS show much better agreement
that the first MCS is most likely from south-central Nebraska into
east-central Kansas, and this is where the Slight Risk was
maintained. For the second MCS, EAS probabilities are lower,
indicating lower confidence and more spread on placement.
Therefore, it's not certain that the rainfall footprints of both
will overlap to a considerable degree; if that does happen, it
would make flash flooding more likely. However, rain rates in the
first MCS may be sufficiently high (1-2 inches per hour) to pose a
flash flooding threat on its own.

...Bertha/South Texas...

16Z UPDATE: No major changes were made to the outlook with this
update, other than small tweaks to account for the latest
observational trends and new 12Z hi-res model runs. A slow-moving
front will continue to act as a focus for training convective rain
bands and thunderstorms from the Upper Tennessee Valley into North
Carolina, southeast Virginia, and the far southern Delmarva
Peninsula. Although hi-res guidance now indicates less persistence
and focus to the convective activity overnight, with somewhat lower
rain threshold and FFG exceedance probabilities, the Moderate Risk
was maintained for continuity and a favorable pattern for training
convection. Within the Moderate Risk area, signals remain strongest
in the Hampton Roads area.

Meanwhile, the level of concern is increasing for later tonight for
the southern Appalachians, in particular the mountainous areas of
eastern Tennessee and western North Carolina, and perhaps far
northern Georgia. Deep moisture is expected to increase over the
next 12 hours as a more direct connection is made with some of the
low-mid level moisture associated with Bertha along the Gulf Coast.
This can be seen in the CIRA layer precipitable water products from
the Surface to 850mb, as well as 850-700mb. There has already been
a concerted northward push of anomalous moisture, and the PWAT at
BMX increased from 1.86 inches to 2.10 inches between the 06 UTC
and 12 UTC balloon launches. As this reaches the stalling front
tonight, with increasing westerly low-level flow parallel to that
front, ingredients will become favorable for reinvigoration of a
training and backbuilding convective band in the vicinity of the
southern Appalachians. QPF signals in the hi-res models have
increased, with some chances of rain rates reaching 2 inches per
hour if organized thunderstorms can become established. Therefore,
although the risk level is being held at Slight, this area will be
monitored closely in case a targeted upgrade is needed.

Models continue to show a coherent signal for heavy rainfall
through South Texas, related to a convective cluster well displaced
from Bertha's center. A Slight Risk upgrade was considered given
the deep tropical moisture that is likely to be present, however
this is also mitigated by extremely dry antecedent conditions
(rainfall less than 25 percent of normal in the past month). FFG in
South Texas is among the highest in the country at the moment.
Finally, all models show a steady westward progression of the
convection, such that it doesn't linger in any one spot for more
than a few hours. Considering that, and in collaboration with WFOs
in Corpus Christi and Brownsville, the risk level was held at a
Marginal Risk for now.

Lamers

Day 3
Valid 12Z Fri Jul 24 2026 - 12Z Sat Jul 25 2026

..THERE ARE SLIGHT RISKS OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
SOUTHEAST AS WELL AS FOR MUCH OF MISSOURI...

...Southeast...

The continued presence of the stalled front in the Southeast should
continue to focus additional rounds of convection on Friday,
although given the lead time the placement is more uncertain. While
the front itself may become more diffuse, this may be counteracted
by decreasing deep layer mean flow as an upper level ridge axis
builds in (potential for slower storm motions) and increasing
precipitable water. Models actually show a much larger area of
PWATs in excess of 2 inches than prior days, and combined with
relatively strong instability, the environment would be very
supportive of intense rain rates exceeding 2 inches per hour at
times. If these more intense rain rates intersect (and persist)
over areas that received heavy rain in prior days, or some of the
major urban centers in the Southeast, then some locally significant
flash flooding could result. Portions of the region will be
monitored for a potential upgrade to Moderate Risk. Right now that
seems most likely from north-central Alabama into north Georgia,
and the eastern Carolinas, but it's important to stay tuned for
future updates as a lot will likely depend on convective evolution
over the next two days.

...Eastern Kansas and Missouri...

The Slight Risk was maintained and is still centered on much of
Missouri. This will be a continuation of convective activity from
the Day 2 period. It should be noted there is considerable spread
in the position of a potential MCS among available reliable
guidance members. For example, the 12Z ECMWF has the rainfall
maximum centered in northeast Missouri, to the north of St. Louis.
Meanwhile, the 12Z AI-GFS and RRFS are as far away as southeast
Kansas, a displacement of around 200 miles. These different model
scenarios depict dry or nearly dry conditions where the other has a
corridor of very heavy rain. This obviously has implications for
narrowing down the risk area. For now the Slight Risk was kept
fairly broad to account for model spread, and a large area with at
least a 15 percent chance of flash flooding as a result. This may
get narrowed with time.

Lamers

Day 4 and Day 5

Valid 12Z Sat Jul 25 2026 - 12Z Mon Jul 27 2026

...THERE IS A MARGINAL RISK FOR EXCESSIVE RAINFALL FROM THE MID
MISSISSIPPI VALLEY THROUGH THE CAROLINAS DAY 4, A PORTION OF THE
UPPER MIDWEST ON DAY 5, AND ACROSS PORTIONS OF THE WESTERN U.S.
DAYS 4 AND 5...

...Mid Mississippi Valley to the Southeast...
The trend with Carolina Coast QPF on Saturday went slower meaning
more rain along the Coast. It seems fine to continue with just a
Marginal Risk for Day 4, though that was expanded back inland a
bit to encompass all of eastern NC. Given the high amounts of
rainfall forecast over eastern NC over the next few days, any
further trend inland would warrant a reintroduction of a Slight
Risk.

Widened the Day 4 Marginal Risk over southeast Missouri given some
uncertainty on the frontal placement there. The 12Z RRFS is also
farther west over south-central MO Saturday afternoon. Otherwise,
the expectation is still for elevated storms to then propagate
southeast through the Mid South/TN Valley with deepening moisture
and training activity likely. Additional activity further
downstream along the front is likely over northern AL/much of GA
where the Marginal Risk remains.

...Southwest to the northern Rockies...
Monsoonal flow through the Intermountain West continues this
weekend. EC/GFS PW anomalies are lacking over AZ for Saturday, but
elevated over NM/CO/UT into WY. Moisture is more anomalous over all
these states on Sunday. The Day 4/5 Marginal Risks are similarly
drawn for both days with less coverage in northern AZ maintained
for Day 4. Furthermore, the Sacramento Mtns of NM were added to Day
5 given model QPF there along with some added moisture.

...Great Lakes...
Decent agreement among guidance for anomalously high moisture
shift to shift east from the northern Plains through the Upper
Midwest on Sunday on the top side of the upper high centered over
the TX Panhandle. This is a northwest flow scenario and where it
parallels any boundaries, repeating convection should occur. As of
now the heavy rain threat area seems centered on Wisconsin per
recent EC-AIFS and PW anomaly positioning from the EC/GFS. The
placement should be refined with time, but the presence of
repeating heavy thunderstorms has enough confidence to raise a Day
5 Marginal over Wisconsin into the LP of Michigan.

Jackson/Pereira

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!64q9FRAwIKgOVnGkkCNvDw4aVEZ3ixJd-wmwuXodSCp7DA6dpHqUKWiNR7iNz63JtB6ontSXCAL6CutjtaLZCU9Plu0$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!64q9FRAwIKgOVnGkkCNvDw4aVEZ3ixJd-wmwuXodSCp7DA6dpHqUKWiNR7iNz63JtB6ontSXCAL6CutjtaLZZQ8NFk4$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!64q9FRAwIKgOVnGkkCNvDw4aVEZ3ixJd-wmwuXodSCp7DA6dpHqUKWiNR7iNz63JtB6ontSXCAL6CutjtaLZ1dzr0WY$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Jul 23 07:15:14 2026

FOUS30 KWBC 230714
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
314 AM EDT Thu Jul 23 2026

Day 1
Valid 12Z Thu Jul 23 2026 - 12Z Fri Jul 24 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
CENTRAL TO NORTHEASTERN NORTH CAROLINA INTO FAR SOUTHEASTERN
VIRGINIA...

...Southeast...

Very few changes were needed with this morning's update across the
Southeast, and the forecast remains on track. Unfortunately what
also remains on track are these very persistent lines of showers
and thunderstorms tracking across central North Carolina and into
the Hampton Roads area of Virginia. This is being driven by a
strong but essentially stalled out front over Virginia. Anomalous
moisture streaming northeastward along the front is originating out
of the Gulf and T.S. Bertha. Thus, the constant moisture supply is
effectively replacing any moisture lost to heavy rain, so the
storms can persist. The front could make a bit more southward
progress down the Piedmont of southern Virginia and central North
Carolina. This should gradually diminish areal rainfall totals with
increasing longitude. Thus, the inherited Moderate Risk targeting
northeastern NC and nearby areas remains in place, since the rain
is likely to persist into that area right through the day today and
the night tonight. Urban concerns into Virginia Beach, Norfolk,
Chesapeake, and Portsmouth will remain front and center for the
risk of potential impacts from flash flooding. Thus, despite some
agreement that most of the heaviest rains eventually push south of
those cities tonight, the urban areas lowering FFGs could still
result in numerous flash floods today into tonight.

The western extension of the front into the western Carolinas
through northern Georgia, Alabama, and Mississippi will continue to
promote localized instances of flash flooding due to training
storms, following the exact same mechanisms as described above. The
only difference is the storms are likely to struggle a bit more to
organize, so fewer extreme rainfall amounts are expected from the
Atlanta Metro west. The Slight Risk is primarily for urban areas.

...Central Plains...

The inherited pair of Slight Risks were only tweaked to match with
the latest guidance around the edge of the risk areas with this
update. Across the east, an MCS will impact portions of Nebraska
into Kansas early this morning, but should generally be fast moving
and the rain will fall over dry soils. The primary concern for the
Slight Risk is for tonight as a new MCS develops. This one will be significantly slower-moving. The MCS will have a robust LLJ
tracking due north up the Plains to replenish all rain lost to
rainfall. Thus, expect more instances of flash flooding tonight.
Across the west, over eastern Colorado, the flash-flood risk will
be in the late afternoon and evening during peak heating, as the
upper level support and monsoonal moisture will promote more
widespread but less organized convection as compared to the MCS
impacting areas further east. Guidance has been consistent on the
location of the heaviest rains, with little change in the
magnitudes as well. Thus, few changes were needed.

...Bertha/South Texas...

T.S. Bertha will continue tracking west into Texas. There is
expected to be a period of time where the center remains over water
over the far northwestern Gulf. This should allow the associated
convection, which has always been displaced well southwest of
center due to strong northeasterly shear, to eventually move into
portions of south Texas. Therefore, the heaviest rains with the
entire storm are likely to impact south Texas. There remains some
potential that coastal areas such as around Corpus Christi could
eventually need a Slight, or locally see Slight level impacts. But
since most of south Texas remains dry, much of Bertha's rains in
the area will be beneficial, with only isolated instances of flash
flooding. Thus, the Marginal Risk in this area was left little
changed with this update.

...Southwest...

Both available monsoonal moisture and forcings will diminish today
as compared to the scattered convection seen on Wednesday. Thus, a
Marginal Risk was left in the areas where convection will be most
prevalent, generally for Colorado, Wyoming, and Utah. While some
showers and storms may impact areas further west, into Arizona,
Nevada, and into Idaho, both coverage and intensity there will be
much less, so the threat should be less than 5% for most areas of
those states.

Wegman

Day 2
Valid 12Z Fri Jul 24 2026 - 12Z Sat Jul 25 2026

...THERE ARE SLIGHT RISKS OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE SOUTHEAST AS WELL AS FOR MISSOURI AND NORTHEASTERN KANSAS...

...Southeast...

The front impacting the Carolinas remains solidly in place on
Friday as steadily training bands of showers and storms track along
the front along the coast of the Carolinas. The heaviest rainfall
totals do shift a bit from Thursday, focusing right along the coast
from central South Carolina through much of the Outer Banks to
Albemarle Sound. Hopefully, that southward shift allows for areas
to the north very hard hit both now and on Thursday to get far less
rainfall by Friday, albeit not quite none. Localized intrusions of
warmer air over southern Virginia may allow for brief showers and
storms to impact some of the hard-hit areas, but total rainfall
does not look to be impactful, especially as those hard hit areas
will still be recovering from today's rainfall. This general lack
of overlap of the heaviest rainfall from Wednesday to Thursday, and
the focus over generally flood-resistant areas of the Low Country
to the Outer Banks allowed for the risk area to remain at a Slight,
and a Moderate upgrade was not considered. Once again, the front
extends back to the west over northern Georgia, Alabama, and
Mississippi, so the Slight was continued a second day from
Birmingham through Atlanta.

...Missouri and Kansas...

An ongoing MCS at the start of the Friday period will be the
primary animus for flash flooding across northeastern Kansas and
extending across much of northern and central Missouri on Friday.
The MCS is likely to persist through midday, diminishing through
the afternoon. Comparatively very little convection is expected
Friday night over this area, so the flooding focus will be almost
entirely Friday morning. Urban concerns in Kansas City and
eventually into St. Louis will pose the biggest impact concerns.

...Southwest...

Convection remains very widely scattered across the 4 Corners
region on Friday. Nominally higher flash flooding threat will exist
over eastern New Mexico and into the Texas Panhandle. The area is
very dry going in, so most of the rain will be beneficial for
impacted areas. An isolated flash flooding threat will remain.

Wegman

Day 3
Valid 12Z Sat Jul 25 2026 - 12Z Sun Jul 26 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR THE COASTAL
CAROLINAS...

...Southeast through the Tennessee Valley...

A deepening longwave trough pushing south down the East Coast on
Saturday will finally provide a push to the stalled out front over
the Carolinas to allow it to push through the coast and offshore by
Saturday night. Thus, Saturday will be the last day where heavy
rainfall will threaten the coastal Carolinas. However, given prior
days' rains, especially the rain expected on Friday, a Slight Risk
upgrade was introduced with this update. Fortunately, outside of
urban areas such as Wilmington, Myrtle Beach, and perhaps
Charleston, SC on the south side, flat terrain, sandy soils, and
vegetation should all help to suppress the flooding risk a good
bit, despite the heavy rainfall from Friday continuing into
Saturday.

Further west across the Tennessee Valley, the front will remain
stuck, as the aforementioned longwave trough only advances east of
the Appalachians, so the Tennessee Valley will remain in a warm
advection regime, allowing for periodic showers and thunderstorms
to move over cities such as Nashville, Chattanooga, and Huntsville
again on Saturday. In addition to topographic concerns, it's
probable this area may also need a Slight Risk upgrade in coming
days once the events move into CAMs range and amounts (typically)
rise.

...Southwest...

The monsoon recharges and resets across the 4 Corners region on
Saturday. A westward moving shortwave moves up the Rio Grande,
which when added to renewed monsoonal moisture, will make for a
renewed round of afternoon showers and thunderstorms capable of
flash flood producing amounts of rain across central and western
New Mexico and into southeastern Arizona. Given the recent wet
weather and the expected intensity and organization of the storms
in this region on Saturday, here too appears probable to need a
Slight Risk upgrade for some areas as the event moves into the CAMs
range.

Wegman

Day 4 and Day 5

Valid 12Z Sun Jul 26 2026 - 12Z Tue Jul 28 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE WESTERN U.S. AND ACROSS THE UPPER MIDWEST AND GREAT LAKES
REGION INTO THE OHIO VALLEY AND CENTRAL APPALACHIANS SUNDAY
THROUGH TUESDAY...

...Southwest to the northern Rockies...
Monsoonal flow through the Intermountain West continues into early
next week. EC/GFS PW anomalies are highest (closer to 2 standard
deviations above normal) across AZ, especially southern AZ on Day 4
(12Z Sun-12Z Mon) with PWs between 1.75-2.00". Suspect southern AZ
could eventually see a Slight Risk area during this period,
especially considering the higher likelihood of more vigorous
shortwave activity rotating westward south of the mid/upper level
ridge. For now however will maintain the Marginal Risk, given the
spread in the global guidance and current low probabilities of
greater than 1-2" of QPF within the 24hr period.

For Day 5 (12Z Mon-12Z Tue), essentially minor adjustments to the
broad Marginal Risk area across the 4-Corners, Southwest, central
Rockies, and central High Plains. The globals (ECMWF, GFS, and
CMC) all show convectively-aided shortwave activity traversing W-E
overtop the flattening mid-upper ridge, into the central High
Plains, which would explain the eastward expansion of the Marginal
Risk area from the Day 4 ERO. Global ensembles also show an uptick
in PW anomalies into the central High Plains as well during this
time, along with an increase in areal-average QPF.

...Upper Midwest-Great Lakes-Ohio Valley-Central Appalachians...
Global guidance, to varying degrees, continues to show
convectively-aided shortwave activity riding down the top side of
the upper ridge. The guidance shows these ridge crawlers becoming a
bit better organized through the day 4-5 period, with an uptick in
deep-layer QG forcing (Qs convergence) and increasing low-level
moisture transport. For now, have maintained the relatively compact
Marginal Risk on Day 4, while introducing a broader Marginal Risk
on Day 5 stretching through the Great Lakes, OH Valley, and Central Appalachians. At this point, given the spread in the guidance QPFs,
along with the strong low-mid level shear with the deep northwest
flow and progressive north-northwest MBE/Corfidi Vectors, will cap
the ERO risk at Marginal.

Hurley

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!_ctQ9kcoKVz55egjFhEsxh4Bpu4Vj19MWseMB8Qss0V2NoAyMikB0otwv_2ZtST7tXaAK6HFfHWN48XJn6XBorgKRWE$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!_ctQ9kcoKVz55egjFhEsxh4Bpu4Vj19MWseMB8Qss0V2NoAyMikB0otwv_2ZtST7tXaAK6HFfHWN48XJn6XB998we_c$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!_ctQ9kcoKVz55egjFhEsxh4Bpu4Vj19MWseMB8Qss0V2NoAyMikB0otwv_2ZtST7tXaAK6HFfHWN48XJn6XBkrNHnSI$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Jul 23 15:57:24 2026

FOUS30 KWBC 231557
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1157 AM EDT Thu Jul 23 2026

Day 1
Valid 16Z Thu Jul 23 2026 - 12Z Fri Jul 24 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL IN PORTIONS OF THE
SOUTHEAST, AND CENTRAL ROCKIES INTO THE CENTRAL PLAINS...

...Southeast...

The latest observational trends this morning -- in surface obs,
radar, and satellite -- suggest the stalling front (modified by
convective outflow) is situated across southern North Carolina.
Relatively dense cloud cover, light-moderate rain, and northeast
flow with falling dew points are prevailing to the north. This is
expected to reduce the threat for stronger and organized convective
activity across northern North Carolina and southern Virginia, and
therefore the primary change with this update was to trend the risk
level down in those areas, and remove the Moderate Risk.

The threat of organized convection with heavy rain rates will not
vanish entirely though, but should be favored further south of
areas that have been affected in recent days, particularly from
northern Alabama and northern Georgia into northern South Carolina
and southern and eastern North Carolina. Precipitable water values
remain quite high, around or above 2 inches over that region, so
rain rates may reach 2 inches per hour in areas where sufficient
instability can build. With deep layer mean flow continuing from a
westerly direction, there will be opportunities for some training
of convective clusters and line segments, and this would be the
most likely mechanism for flash flooding.

It should be noted that, although there is now a Slight Risk across
all of eastern North Carolina, the potential remains for localized
significant rainfall and flash flood events. Hi-res ensemble
guidance (HREF and REFS) do indicate some small probabilities of
rainfall totals today exceeding 5 inches in E NC, but there was a
slight reduction in the chances. Additionally, southeast NC has not
experienced the amount of recent rainfall as other parts of the
state, so antecedent conditions are somewhat dry. Nevertheless, if
high rain rates can train long enough, and/or intersect urban
locations, there may be the potential for an isolated significant
flash flood impact. Otherwise, isolated to scattered instances of
flash flooding are expected across the Slight Risk area.

...Central Rockies into the Central Plains...

The inherited risk areas from the Central Rockies (primarily UT,
WY, CO) into the central Plains (primarily NE, KS) were left
largely unchanged other than some small tweaks. Uncertainty is
higher in this area. Given that, we opted for consistency in this
outlook update, especially as the two Slight Risk areas are still
anchored fairly close to the areas where QPF is maximized (in a
regional sense) on the hi-res ensembles and AI guidance (GFS,
ECMWF). Overall, renewed convective development is expected across
the Central Rockies this afternoon. Although precipitable water
values may be falling slightly relative to recent days, they are
still generally around or above the 90th percentile across much of
the affected region, and rain rates above 1 inch per hour are
still expected in the strongest convection. Overnight, a new MCS
seems likely to develop in the Central Plains. However, while there
is good agreement on the existence of an MCS in the available hi-
res guidance, the positional uncertainty has increased relative to
previous model cycles. The Slight Risk area should be viewed as the
more likely location, but heavy rainfall further north into NE,
IA, or further southwest into W/C KS are also plausible scenarios.

...Bertha/South Texas...

A small cluster of intense convection, displaced well southwest of
Bertha's center, is continuing to propagate west over the Gulf.
Estimated rain rates via MRMS are high, over 3 inches per hour,
which seems to be a reasonable assumption. Projecting this forward
over the next 12 hours is tough, as it may not be a linear trend in
either direction or intensity. Some hi-res models dissipate the
convection quickly upon reaching land (with lower instability), and
others allow it to more-or-less move steadily west-southwest over
South Texas. In coordination with the local forecast offices in
Corpus Christi and Brownsville, the risk level was kept at
Marginal, largely due to the very dry antecedent conditions,
expected steady progression of the convection which would limit the
duration of heavy rain in any one location, and uncertainty on the
location of the heaviest rain. This area will continue to be
monitored in case a targeted Slight Risk upgrade is needed. The
only change was to move the Marginal Risk north very slightly to
account for the latest radar trends.

Lamers

Day 2
Valid 12Z Fri Jul 24 2026 - 12Z Sat Jul 25 2026

...THERE ARE SLIGHT RISKS OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE SOUTHEAST AS WELL AS FOR MISSOURI AND NORTHEASTERN KANSAS...

...Southeast...

The front impacting the Carolinas remains solidly in place on
Friday as steadily training bands of showers and storms track along
the front along the coast of the Carolinas. The heaviest rainfall
totals do shift a bit from Thursday, focusing right along the coast
from central South Carolina through much of the Outer Banks to
Albemarle Sound. Hopefully, that southward shift allows for areas
to the north very hard hit both now and on Thursday to get far less
rainfall by Friday, albeit not quite none. Localized intrusions of
warmer air over southern Virginia may allow for brief showers and
storms to impact some of the hard-hit areas, but total rainfall
does not look to be impactful, especially as those hard hit areas
will still be recovering from today's rainfall. This general lack
of overlap of the heaviest rainfall from Wednesday to Thursday, and
the focus over generally flood-resistant areas of the Low Country
to the Outer Banks allowed for the risk area to remain at a Slight,
and a Moderate upgrade was not considered. Once again, the front
extends back to the west over northern Georgia, Alabama, and
Mississippi, so the Slight was continued a second day from
Birmingham through Atlanta.

...Missouri and Kansas...

An ongoing MCS at the start of the Friday period will be the
primary animus for flash flooding across northeastern Kansas and
extending across much of northern and central Missouri on Friday.
The MCS is likely to persist through midday, diminishing through
the afternoon. Comparatively very little convection is expected
Friday night over this area, so the flooding focus will be almost
entirely Friday morning. Urban concerns in Kansas City and
eventually into St. Louis will pose the biggest impact concerns.

...Southwest...

Convection remains very widely scattered across the 4 Corners
region on Friday. Nominally higher flash flooding threat will exist
over eastern New Mexico and into the Texas Panhandle. The area is
very dry going in, so most of the rain will be beneficial for
impacted areas. An isolated flash flooding threat will remain.

Wegman

Day 3
Valid 12Z Sat Jul 25 2026 - 12Z Sun Jul 26 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR THE COASTAL
CAROLINAS...

...Southeast through the Tennessee Valley...

A deepening longwave trough pushing south down the East Coast on
Saturday will finally provide a push to the stalled out front over
the Carolinas to allow it to push through the coast and offshore by
Saturday night. Thus, Saturday will be the last day where heavy
rainfall will threaten the coastal Carolinas. However, given prior
days' rains, especially the rain expected on Friday, a Slight Risk
upgrade was introduced with this update. Fortunately, outside of
urban areas such as Wilmington, Myrtle Beach, and perhaps
Charleston, SC on the south side, flat terrain, sandy soils, and
vegetation should all help to suppress the flooding risk a good
bit, despite the heavy rainfall from Friday continuing into
Saturday.

Further west across the Tennessee Valley, the front will remain
stuck, as the aforementioned longwave trough only advances east of
the Appalachians, so the Tennessee Valley will remain in a warm
advection regime, allowing for periodic showers and thunderstorms
to move over cities such as Nashville, Chattanooga, and Huntsville
again on Saturday. In addition to topographic concerns, it's
probable this area may also need a Slight Risk upgrade in coming
days once the events move into CAMs range and amounts (typically)
rise.

...Southwest...

The monsoon recharges and resets across the 4 Corners region on
Saturday. A westward moving shortwave moves up the Rio Grande,
which when added to renewed monsoonal moisture, will make for a
renewed round of afternoon showers and thunderstorms capable of
flash flood producing amounts of rain across central and western
New Mexico and into southeastern Arizona. Given the recent wet
weather and the expected intensity and organization of the storms
in this region on Saturday, here too appears probable to need a
Slight Risk upgrade for some areas as the event moves into the CAMs
range.

Wegman

Day 4 and Day 5

Valid 12Z Sun Jul 26 2026 - 12Z Tue Jul 28 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE WESTERN U.S. AND ACROSS THE UPPER MIDWEST AND GREAT LAKES
REGION INTO THE OHIO VALLEY AND CENTRAL APPALACHIANS SUNDAY
THROUGH TUESDAY...

...Southwest to the northern Rockies...
Monsoonal flow through the Intermountain West continues into early
next week. EC/GFS PW anomalies are highest (closer to 2 standard
deviations above normal) across AZ, especially southern AZ on Day 4
(12Z Sun-12Z Mon) with PWs between 1.75-2.00". Suspect southern AZ
could eventually see a Slight Risk area during this period,
especially considering the higher likelihood of more vigorous
shortwave activity rotating westward south of the mid/upper level
ridge. For now however will maintain the Marginal Risk, given the
spread in the global guidance and current low probabilities of
greater than 1-2" of QPF within the 24hr period.

For Day 5 (12Z Mon-12Z Tue), essentially minor adjustments to the
broad Marginal Risk area across the 4-Corners, Southwest, central
Rockies, and central High Plains. The globals (ECMWF, GFS, and
CMC) all show convectively-aided shortwave activity traversing W-E
overtop the flattening mid-upper ridge, into the central High
Plains, which would explain the eastward expansion of the Marginal
Risk area from the Day 4 ERO. Global ensembles also show an uptick
in PW anomalies into the central High Plains as well during this
time, along with an increase in areal-average QPF.

...Upper Midwest-Great Lakes-Ohio Valley-Central Appalachians...
Global guidance, to varying degrees, continues to show
convectively-aided shortwave activity riding down the top side of
the upper ridge. The guidance shows these ridge crawlers becoming a
bit better organized through the day 4-5 period, with an uptick in
deep-layer QG forcing (Qs convergence) and increasing low-level
moisture transport. For now, have maintained the relatively compact
Marginal Risk on Day 4, while introducing a broader Marginal Risk
on Day 5 stretching through the Great Lakes, OH Valley, and Central Appalachians. At this point, given the spread in the guidance QPFs,
along with the strong low-mid level shear with the deep northwest
flow and progressive north-northwest MBE/Corfidi Vectors, will cap
the ERO risk at Marginal.

Hurley

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!_ZHi7-dHkNNbT_N9fxbmFNbz3-EU-qC0nGTXnLDiYnvx_1PNH4pVVVA18YNHSz2OU3Oh6OsiNmP0AHV5cDES3Yh9it8$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!_ZHi7-dHkNNbT_N9fxbmFNbz3-EU-qC0nGTXnLDiYnvx_1PNH4pVVVA18YNHSz2OU3Oh6OsiNmP0AHV5cDES3b54GgM$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!_ZHi7-dHkNNbT_N9fxbmFNbz3-EU-qC0nGTXnLDiYnvx_1PNH4pVVVA18YNHSz2OU3Oh6OsiNmP0AHV5cDES4fhfKIc$

$$

= = =
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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Jul 23 19:32:14 2026

FOUS30 KWBC 231931
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
331 PM EDT Thu Jul 23 2026

Day 1
Valid 1928Z Thu Jul 23 2026 - 12Z Fri Jul 24 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL IN PORTIONS OF THE
SOUTHEAST, AND CENTRAL ROCKIES INTO THE CENTRAL PLAINS...

...Southeast...

The latest observational trends this morning -- in surface obs,
radar, and satellite -- suggest the stalling front (modified by
convective outflow) is situated across southern North Carolina.
Relatively dense cloud cover, light-moderate rain, and northeast
flow with falling dew points are prevailing to the north. This is
expected to reduce the threat for stronger and organized convective
activity across northern North Carolina and southern Virginia, and
therefore the primary change with this update was to trend the risk
level down in those areas, and remove the Moderate Risk.

The threat of organized convection with heavy rain rates will not
vanish entirely though, but should be favored further south of
areas that have been affected in recent days, particularly from
northern Alabama and northern Georgia into northern South Carolina
and southern and eastern North Carolina. Precipitable water values
remain quite high, around or above 2 inches over that region, so
rain rates may reach 2 inches per hour in areas where sufficient
instability can build. With deep layer mean flow continuing from a
westerly direction, there will be opportunities for some training
of convective clusters and line segments, and this would be the
most likely mechanism for flash flooding.

It should be noted that, although there is now a Slight Risk across
all of eastern North Carolina, the potential remains for localized
significant rainfall and flash flood events. Hi-res ensemble
guidance (HREF and REFS) do indicate some small probabilities of
rainfall totals today exceeding 5 inches in E NC, but there was a
slight reduction in the chances. Additionally, southeast NC has not
experienced the amount of recent rainfall as other parts of the
state, so antecedent conditions are somewhat dry. Nevertheless, if
high rain rates can train long enough, and/or intersect urban
locations, there may be the potential for an isolated significant
flash flood impact. Otherwise, isolated to scattered instances of
flash flooding are expected across the Slight Risk area.

...Central Rockies into the Central Plains...

19Z UPDATE: The Marginal Risk was expanded into New Mexico given a
notable increase in convective activity. For more details, please
refer to Mesoscale Precipitation Discussion 832.

PREVIOUS DISCUSSION: The inherited risk areas from the Central
Rockies (primarily UT, WY, CO) into the central Plains (primarily
NE, KS) were left largely unchanged other than some small tweaks.
Uncertainty is higher in this area. Given that, we opted for
consistency in this outlook update, especially as the two Slight
Risk areas are still anchored fairly close to the areas where QPF
is maximized (in a regional sense) on the hi-res ensembles and AI
guidance (GFS, ECMWF). Overall, renewed convective development is
expected across the Central Rockies this afternoon. Although
precipitable water values may be falling slightly relative to
recent days, they are still generally around or above the 90th
percentile across much of the affected region, and rain rates above
1 inch per hour are still expected in the strongest convection.
Overnight, a new MCS seems likely to develop in the Central Plains.
However, while there is good agreement on the existence of an MCS
in the available hi- res guidance, the positional uncertainty has
increased relative to previous model cycles. The Slight Risk area
should be viewed as the more likely location, but heavy rainfall
further north into NE, IA, or further southwest into W/C KS are
also plausible scenarios.

...Bertha/South Texas...

A small cluster of intense convection, displaced well southwest of
Bertha's center, is continuing to propagate west over the Gulf.
Estimated rain rates via MRMS are high, over 3 inches per hour,
which seems to be a reasonable assumption. Projecting this forward
over the next 12 hours is tough, as it may not be a linear trend in
either direction or intensity. Some hi-res models dissipate the
convection quickly upon reaching land (with lower instability), and
others allow it to more-or-less move steadily west-southwest over
South Texas. In coordination with the local forecast offices in
Corpus Christi and Brownsville, the risk level was kept at
Marginal, largely due to the very dry antecedent conditions,
expected steady progression of the convection which would limit the
duration of heavy rain in any one location, and uncertainty on the
location of the heaviest rain. This area will continue to be
monitored in case a targeted Slight Risk upgrade is needed. The
only change was to move the Marginal Risk north very slightly to
account for the latest radar trends.

Lamers

Day 2
Valid 12Z Fri Jul 24 2026 - 12Z Sat Jul 25 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE SOUTHEAST INTO THE OZARKS AND LOWER MISSOURI VALLEY...

...Southeast...

A stalled front will continue to snake across the Southeast,
extending from northern Mississippi, into north-central Alabama and north-central Georgia, and then into the eastern Carolinas. This
will be the focus for renewed convective activity on Friday. Subtle
changes over the next 24 hours may actually make the atmosphere
more supportive of heavy rain rates by Friday afternoon. First,
precipitable water values are projected to increase, largely due to
a steady increase in moisture in the 850-500mb layer. By Friday
afternoon, most of the area along the stalled front should see
PWATs in the 2.1 to 2.4 inch range. Second, the deep layer mean
winds are expected to decrease from around 15-25 knots today, to
around 10-15 knots by Friday afternoon, as an upper level ridge
axis builds in and reduces upper level winds. This should create an
enviornment that favors very high instantaneous rain rates and
slow-moving, backbuilding, and training clusters near the front.

This may be compensated by a weaker front and low-level
convergence, which would tend to favor clusters and line segments
that are more scattered across the region, rather than aligned in a
specific corridor. Nevertheless, there will still be localized
opportunities for periods of training convection that could result
in flash flooding. The chances (based on hi-res ensemble data) of
rain rates in excess of 2 inches per hour, and for 24-hour rainfall
totals in excess of 5 inches, are highest about 40mi either side of
a line from Birmingham AL, to Atlanta GA, to Aiken SC, to Myrtle
Beach SC, to Morehead City NC. In fact, the 12Z HREF even shows
potential for rain rates to exceed 3 inches per hour in this same
corridor, especially in South Carolina (neighborhood probabilities
as high as 30 percent in SC), so the potential for locally
significant flash flooding remains. An upgrade to Moderate Risk
cannot be ruled out if enough observational evidence and model
guidance suggests a corridor of sustained training convection is
becoming more likely.

...Ozarks and Lower Missouri Valley...

An MCS may be ongoing at the start of the period somewhere in the
vicinity of eastern Kansas and Missouri, near the nose of the low-
level jet. The biggest change with this outlook update was to trim
the Slight Risk out of eastern Missouri in collaboration with WFO
St. Louis. A limited number of models still progress heavy rainfall
further east in Missouri, but the consensus now points more clearly
to eastern Kansas and western and central Missouri. This also
aligns with a typical bias in modeled MCS activity in the central
Plains -- it often ends up further into the inflow than models
would suggest.

There is more uncertainty about what happens later in the forecast
period, from late Friday afternoon into Friday Night. Most hi-res
models suggest the convective cluster will progress southeast into
the Ozarks and potentially Mid-Mississippi Valley by 12Z Saturday.
However, they increasingly disagree on placement of the heaviest
rainfall, the convective evolution, and magnitude of the rainfall.

From a pattern recognition standpoint, there is some concern about
an increasingly favorable setup for a backbuilding MCS on Friday
Night. The low-level jet will veer to be more westerly, and the
20-30 knot low-level inflow will exceed the strength of the
increasingly weak 15-20 knot deep layer mean flow. In these
situations, you will occasionally see a convective line backbuild
into the unstable inflow for hours, on the periphery of the cold
pool. The 12Z HRRR is the model that shows this scenario most
clearly, and it generates a maximum of about 6 inches of rain in 6
hours near the AR-MO border late in the forecast period.
Conversely, other hi-res models show scattered convection that is
far less focused. To put it another way, the synoptic evolution
would favor potential for backbuilding storms on Friday Night, but
whether it happens will ultimately come down to specific convective
evolution from the Central Plains over the 24 hours prior, and
probably whether a stronger, more concentrated cold pool can
develop. This area will be monitored closely in future updates.

Lamers

Day 3
Valid 12Z Sat Jul 25 2026 - 12Z Sun Jul 26 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR THE EASTERN
CAROLINAS AND FOR PORTIONS OF NEW MEXICO...

...Southeast through the Tennessee Valley...

The outlook for the Southeast was left fairly consistent with the
previous version with a Slight Risk in the eastern Carolinas, and a
broad Marginal Risk over the rest of the region in the general
vicinity of the lingering front. A key uncertainty is the position
of the front, as earlier models, and still global model guidance is
positioned further north, while hi-res guidance beginning to come
into view for the forecast period (3km NAM, RRFS, REFS) places the
heaviest rain further south. For the time being, the Marginal Risk
was positioned in an intermediate location and close to the
corridor of greatest QPF on the WPC deterministic forecast.
However, the positioning of the risk area may continue to evolve in
future outlook updates. Overall, the environment will still be
favorable for high rain rates in the most organized thunderstorms,
with precipitable water values still expected to be above 2 inches.
However, the expectation of convective activity being more
scattered with an increasingly diffuse frontal boundary may keep
any flash flooding impacts isolated-scattered as well.

...Southwest...

The monsoon recharges and resets across the Four Corners region on
Saturday. A Slight Risk was introduced primarily across New Mexico
where available REFS, RRFS, and 3km NAM hi-res model guidance shows
localized heavy rainfall in the same area as elevated values
approaching 15 percent on the 12Z CSU machine learning ERO
probability guidance. The Slight Risk was concentrated more in
Central New Mexico as models show dry air advection into southern
New Mexico for much of the forecast period. North of that, in C/N
NM, precipitable water values will continue to be around or just
above the 90th percentile for July, and supportive of high rain
rates in any thunderstorms that can develop.

Lamers

Day 4 and Day 5

Valid 12Z Sun Jul 26 2026 - 12Z Tue Jul 28 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE WESTERN U.S. AND ACROSS THE UPPER MIDWEST AND GREAT LAKES
REGION INTO THE OHIO VALLEY AND CENTRAL APPALACHIANS SUNDAY
THROUGH TUESDAY...

...Southwest to the northern Rockies...
Monsoonal flow through the Intermountain West continues into early
next week. EC/GFS PW anomalies are highest (closer to 2 standard
deviations above normal) across AZ, especially southern AZ on Day 4
(12Z Sun-12Z Mon) with PWs between 1.75-2.00". Suspect southern AZ
could eventually see a Slight Risk area during this period,
especially considering the higher likelihood of more vigorous
shortwave activity rotating westward south of the mid/upper level
ridge. For now however will maintain the Marginal Risk, given the
spread in the global guidance and current low probabilities of
greater than 1-2" of QPF within the 24hr period.

For Day 5 (12Z Mon-12Z Tue), essentially minor adjustments to the
broad Marginal Risk area across the 4-Corners, Southwest, central
Rockies, and central High Plains. The globals (ECMWF, GFS, and
CMC) all show convectively-aided shortwave activity traversing W-E
overtop the flattening mid-upper ridge, into the central High
Plains, which would explain the eastward expansion of the Marginal
Risk area from the Day 4 ERO. Global ensembles also show an uptick
in PW anomalies into the central High Plains as well during this
time, along with an increase in areal-average QPF.

...Upper Midwest-Great Lakes-Ohio Valley-Central Appalachians...
Global guidance, to varying degrees, continues to show
convectively-aided shortwave activity riding down the top side of
the upper ridge. The guidance shows these ridge crawlers becoming a
bit better organized through the day 4-5 period, with an uptick in
deep-layer QG forcing (Qs convergence) and increasing low-level
moisture transport. For now, have maintained the relatively compact
Marginal Risk on Day 4, while introducing a broader Marginal Risk
on Day 5 stretching through the Great Lakes, OH Valley, and Central Appalachians. At this point, given the spread in the guidance QPFs,
along with the strong low-mid level shear with the deep northwest
flow and progressive north-northwest MBE/Corfidi Vectors, will cap
the ERO risk at Marginal.

Hurley

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!7iBPOYsPmSSD_VC5MXOI69Yf-H2CEUlqWhbkSqNA4UwmwPdRe0tgX8MIjvnhTHYwvama0qn8v7SkO9kazdUSqlWeFcM$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!7iBPOYsPmSSD_VC5MXOI69Yf-H2CEUlqWhbkSqNA4UwmwPdRe0tgX8MIjvnhTHYwvama0qn8v7SkO9kazdUSJz8k2fs$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!7iBPOYsPmSSD_VC5MXOI69Yf-H2CEUlqWhbkSqNA4UwmwPdRe0tgX8MIjvnhTHYwvama0qn8v7SkO9kazdUSvfy2JCc$

$$

= = =
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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Jul 23 19:55:00 2026

FOUS30 KWBC 231954
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
354 PM EDT Thu Jul 23 2026

Day 1
Valid 1928Z Thu Jul 23 2026 - 12Z Fri Jul 24 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL IN PORTIONS OF THE
SOUTHEAST, AND CENTRAL ROCKIES INTO THE CENTRAL PLAINS...

...Southeast...

The latest observational trends this morning -- in surface obs,
radar, and satellite -- suggest the stalling front (modified by
convective outflow) is situated across southern North Carolina.
Relatively dense cloud cover, light-moderate rain, and northeast
flow with falling dew points are prevailing to the north. This is
expected to reduce the threat for stronger and organized convective
activity across northern North Carolina and southern Virginia, and
therefore the primary change with this update was to trend the risk
level down in those areas, and remove the Moderate Risk.

The threat of organized convection with heavy rain rates will not
vanish entirely though, but should be favored further south of
areas that have been affected in recent days, particularly from
northern Alabama and northern Georgia into northern South Carolina
and southern and eastern North Carolina. Precipitable water values
remain quite high, around or above 2 inches over that region, so
rain rates may reach 2 inches per hour in areas where sufficient
instability can build. With deep layer mean flow continuing from a
westerly direction, there will be opportunities for some training
of convective clusters and line segments, and this would be the
most likely mechanism for flash flooding.

It should be noted that, although there is now a Slight Risk across
all of eastern North Carolina, the potential remains for localized
significant rainfall and flash flood events. Hi-res ensemble
guidance (HREF and REFS) do indicate some small probabilities of
rainfall totals today exceeding 5 inches in E NC, but there was a
slight reduction in the chances. Additionally, southeast NC has not
experienced the amount of recent rainfall as other parts of the
state, so antecedent conditions are somewhat dry. Nevertheless, if
high rain rates can train long enough, and/or intersect urban
locations, there may be the potential for an isolated significant
flash flood impact. Otherwise, isolated to scattered instances of
flash flooding are expected across the Slight Risk area.

...Central Rockies into the Central Plains...

19Z UPDATE: The Marginal Risk was expanded into New Mexico given a
notable increase in convective activity. For more details, please
refer to Mesoscale Precipitation Discussion 832.

PREVIOUS DISCUSSION: The inherited risk areas from the Central
Rockies (primarily UT, WY, CO) into the central Plains (primarily
NE, KS) were left largely unchanged other than some small tweaks.
Uncertainty is higher in this area. Given that, we opted for
consistency in this outlook update, especially as the two Slight
Risk areas are still anchored fairly close to the areas where QPF
is maximized (in a regional sense) on the hi-res ensembles and AI
guidance (GFS, ECMWF). Overall, renewed convective development is
expected across the Central Rockies this afternoon. Although
precipitable water values may be falling slightly relative to
recent days, they are still generally around or above the 90th
percentile across much of the affected region, and rain rates above
1 inch per hour are still expected in the strongest convection.
Overnight, a new MCS seems likely to develop in the Central Plains.
However, while there is good agreement on the existence of an MCS
in the available hi- res guidance, the positional uncertainty has
increased relative to previous model cycles. The Slight Risk area
should be viewed as the more likely location, but heavy rainfall
further north into NE, IA, or further southwest into W/C KS are
also plausible scenarios.

...Bertha/South Texas...

A small cluster of intense convection, displaced well southwest of
Bertha's center, is continuing to propagate west over the Gulf.
Estimated rain rates via MRMS are high, over 3 inches per hour,
which seems to be a reasonable assumption. Projecting this forward
over the next 12 hours is tough, as it may not be a linear trend in
either direction or intensity. Some hi-res models dissipate the
convection quickly upon reaching land (with lower instability), and
others allow it to more-or-less move steadily west-southwest over
South Texas. In coordination with the local forecast offices in
Corpus Christi and Brownsville, the risk level was kept at
Marginal, largely due to the very dry antecedent conditions,
expected steady progression of the convection which would limit the
duration of heavy rain in any one location, and uncertainty on the
location of the heaviest rain. This area will continue to be
monitored in case a targeted Slight Risk upgrade is needed. The
only change was to move the Marginal Risk north very slightly to
account for the latest radar trends.

Lamers

Day 2
Valid 12Z Fri Jul 24 2026 - 12Z Sat Jul 25 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE SOUTHEAST INTO THE OZARKS AND LOWER MISSOURI VALLEY...

...Southeast...

A stalled front will continue to snake across the Southeast,
extending from northern Mississippi, into north-central Alabama and north-central Georgia, and then into the eastern Carolinas. This
will be the focus for renewed convective activity on Friday. Subtle
changes over the next 24 hours may actually make the atmosphere
more supportive of heavy rain rates by Friday afternoon. First,
precipitable water values are projected to increase, largely due to
a steady increase in moisture in the 850-500mb layer. By Friday
afternoon, most of the area along the stalled front should see
PWATs in the 2.1 to 2.4 inch range. Second, the deep layer mean
winds are expected to decrease from around 15-25 knots today, to
around 10-15 knots by Friday afternoon, as an upper level ridge
axis builds in and reduces upper level winds. This should create an
enviornment that favors very high instantaneous rain rates and
slow-moving, backbuilding, and training clusters near the front.

This may be compensated by a weaker front and low-level
convergence, which would tend to favor clusters and line segments
that are more scattered across the region, rather than aligned in a
specific corridor. Nevertheless, there will still be localized
opportunities for periods of training convection that could result
in flash flooding. The chances (based on hi-res ensemble data) of
rain rates in excess of 2 inches per hour, and for 24-hour rainfall
totals in excess of 5 inches, are highest about 40mi either side of
a line from Birmingham AL, to Atlanta GA, to Aiken SC, to Myrtle
Beach SC, to Morehead City NC. In fact, the 12Z HREF even shows
potential for rain rates to exceed 3 inches per hour in this same
corridor, especially in South Carolina (neighborhood probabilities
as high as 30 percent in SC), so the potential for locally
significant flash flooding remains. An upgrade to Moderate Risk
cannot be ruled out if enough observational evidence and model
guidance suggests a corridor of sustained training convection is
becoming more likely.

...Ozarks and Lower Missouri Valley...

An MCS may be ongoing at the start of the period somewhere in the
vicinity of eastern Kansas and Missouri, near the nose of the low-
level jet. The biggest change with this outlook update was to trim
the Slight Risk out of eastern Missouri in collaboration with WFO
St. Louis. A limited number of models still progress heavy rainfall
further east in Missouri, but the consensus now points more clearly
to eastern Kansas and western and central Missouri. This also
aligns with a typical bias in modeled MCS activity in the central
Plains -- it often ends up further into the inflow than models
would suggest.

There is more uncertainty about what happens later in the forecast
period, from late Friday afternoon into Friday Night. Most hi-res
models suggest the convective cluster will progress southeast into
the Ozarks and potentially Mid-Mississippi Valley by 12Z Saturday.
However, they increasingly disagree on placement of the heaviest
rainfall, the convective evolution, and magnitude of the rainfall.

From a pattern recognition standpoint, there is some concern about
an increasingly favorable setup for a backbuilding MCS on Friday
Night. The low-level jet will veer to be more westerly, and the
20-30 knot low-level inflow will exceed the strength of the
increasingly weak 15-20 knot deep layer mean flow. In these
situations, you will occasionally see a convective line backbuild
into the unstable inflow for hours, on the periphery of the cold
pool. The 12Z HRRR is the model that shows this scenario most
clearly, and it generates a maximum of about 6 inches of rain in 6
hours near the AR-MO border late in the forecast period.
Conversely, other hi-res models show scattered convection that is
far less focused. To put it another way, the synoptic evolution
would favor potential for backbuilding storms on Friday Night, but
whether it happens will ultimately come down to specific convective
evolution from the Central Plains over the 24 hours prior, and
probably whether a stronger, more concentrated cold pool can
develop. This area will be monitored closely in future updates.

Lamers

Day 3
Valid 12Z Sat Jul 25 2026 - 12Z Sun Jul 26 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR THE EASTERN
CAROLINAS AND FOR PORTIONS OF NEW MEXICO...

...Southeast through the Tennessee Valley...

The outlook for the Southeast was left fairly consistent with the
previous version with a Slight Risk in the eastern Carolinas, and a
broad Marginal Risk over the rest of the region in the general
vicinity of the lingering front. A key uncertainty is the position
of the front, as earlier models, and still global model guidance is
positioned further north, while hi-res guidance beginning to come
into view for the forecast period (3km NAM, RRFS, REFS) places the
heaviest rain further south. For the time being, the Marginal Risk
was positioned in an intermediate location and close to the
corridor of greatest QPF on the WPC deterministic forecast.
However, the positioning of the risk area may continue to evolve in
future outlook updates. Overall, the environment will still be
favorable for high rain rates in the most organized thunderstorms,
with precipitable water values still expected to be above 2 inches.
However, the expectation of convective activity being more
scattered with an increasingly diffuse frontal boundary may keep
any flash flooding impacts isolated-scattered as well.

...Southwest...

The monsoon recharges and resets across the Four Corners region on
Saturday. A Slight Risk was introduced primarily across New Mexico
where available REFS, RRFS, and 3km NAM hi-res model guidance shows
localized heavy rainfall in the same area as elevated values
approaching 15 percent on the 12Z CSU machine learning ERO
probability guidance. The Slight Risk was concentrated more in
Central New Mexico as models show dry air advection into southern
New Mexico for much of the forecast period. North of that, in C/N
NM, precipitable water values will continue to be around or just
above the 90th percentile for July, and supportive of high rain
rates in any thunderstorms that can develop.

Lamers

Day 4 and Day 5

Valid 12Z Sun Jul 26 2026 - 12Z Tue Jul 28 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL ACROSS THE FOUR
CORNERS STATES, EXTENDING INTO THE CENTRAL PLAINS MONDAY AND OVER
THE GREAT LAKES, EXTENDING INTO THE NORTHEAST ON MONDAY...

...Four Corners States onto the Central Plains...

Monsoonal flow from the Desert Southwest to the central Rockies
continues into early next week. 12Z EC/GFS PW anomalies are
offset with the EC farther west (NM and CO) vs the GFS (over AZ/NV)
Maintaining Marginal Risks for now, but will continue to note that
shortwave impulses coming up from Mexico could enhance precip and
warrant a Slight Risk. Was able to remove part of southwest WY
given confidence on anomalous moisture being contained south from
the Uinta Mtns.

For Day 5 (12Z Mon-12Z Tue), the amendments to the Marginal Risk
were terrain based on the western side and farther onto the central
Plains (western Nebraska/Kansas) given output from the 12Z EC and
EC-AIFS. However, just like on Day 4, the EC is notably farther
east with anomalous moisture than the GFS. Either way,
convectively-aided shortwave activity should still traverse W-E
overtop the flattening mid- upper ridge into the central High
Plains.

...Upper Midwest-Great Lakes-Ohio Valley-Interior Northeast...

Global and AI guidance continue to show convectively-aided
shortwave activity riding down the top side of the upper ridge axis
over the western Dakota border in northwest flow. Guidance still shows
these ridge crawlers becoming a bit better organized through the
day 4-5 period, with an uptick in deep-layer QG forcing (Qs
convergence) and increasing low-level moisture transport. Broadened
the Marginal Risk on Day 4 to Duluth per the 12Z RRFS and into
northeast Iowa per the EC-AIFS. There is potential for this western
side to then proceed into Day 5/Monday in Illinois, but for now
the Day 5 Marginal Risk was expanded west through Indiana and
northern Kentucky. There is still notable spread in global guidance
for both of these days, but the threat for the NWly flow to become
parallel to any boundaries warrants the Marginal Risks given
enhanced moisture accompanying this activity.

Jackson/Hurley

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!452vvPeVtD13hiXjBdiB0N9BFLYX_ABQIiux3QWfvsW1O9MgXB1eL3oVSTaWZ6EU3iEKvdPRwvfiDdXX6RQQZDTMPjE$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!452vvPeVtD13hiXjBdiB0N9BFLYX_ABQIiux3QWfvsW1O9MgXB1eL3oVSTaWZ6EU3iEKvdPRwvfiDdXX6RQQDaJmbRw$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!452vvPeVtD13hiXjBdiB0N9BFLYX_ABQIiux3QWfvsW1O9MgXB1eL3oVSTaWZ6EU3iEKvdPRwvfiDdXX6RQQmMYxNqQ$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Thu Jul 23 23:30:56 2026

FOUS30 KWBC 232330
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
730 PM EDT Thu Jul 23 2026

Day 1
Valid 01Z Fri Jul 24 2026 - 12Z Fri Jul 24 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL IN PORTIONS OF THE
SOUTHEAST, CENTRAL ROCKIES, AND CENTRAL PLAINS...

...Southeast...

Good agreement among recent HRRR and RRFS runs for heaviest precip
through the overnight along an axis from northern AL through north Georgia/South Carolina and southern North Carolina. Precipitable
water values remain quite high, around or above 2 inches along this
swath, so rain rates should continue to reach 2 inches per hour in
areas where sufficient instability remains. With deep layer mean
flow continuing from a westerly direction, there will be some
training of convective clusters and line segments and thus flash
flooding. Southern NC remains the favorite spot from the HRRR for
greatest overnight rainfall, potentially in the 3-6" range inland
from Wilmington. The higher end (aka "enhanced") Slight Risk
remains in effect for this swath from northern AL through southern
NC. For further information over the Carolinas and north Georgia
this evening, please see MPD 833.

...Desert Southwest, Central Rockies through Central Plains...

23Z UPDATE: The Marginal Risk was further expanded over northern
Arizona for ongoing monsoonal activity.

Two Slight Risk areas maintained for CO and northeast KS where CAM QPF
remains maximized. Recent HRRR/RRFS runs also favor south-central
KS overnight, but that area has high FFG, so a Marginal Risk
remains.

...Bertha/South Texas...

Bertha is onshore north of Houston with heavy, slow moving
convective development on the west side of the Houston metro. This
activity will continue slow west-southwestward progress overnight.
The Marginal Risk was expanded well north and now includes the San
Antonio metro area as well (But south of the Hill Country. MPD 834
has further information for this evening.

Farther south scattered convective activity has continues northwest
of the McAllen metro/Lower Rio Grande Valley and is shifting west.
There is a risk for heavy rain between there and the western
Houston metro area where the Marginal Risk now covers.

Jackson

Day 2
Valid 12Z Fri Jul 24 2026 - 12Z Sat Jul 25 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE SOUTHEAST INTO THE OZARKS AND LOWER MISSOURI VALLEY...

...Southeast...

A stalled front will continue to snake across the Southeast,
extending from northern Mississippi, into north-central Alabama and north-central Georgia, and then into the eastern Carolinas. This
will be the focus for renewed convective activity on Friday. Subtle
changes over the next 24 hours may actually make the atmosphere
more supportive of heavy rain rates by Friday afternoon. First,
precipitable water values are projected to increase, largely due to
a steady increase in moisture in the 850-500mb layer. By Friday
afternoon, most of the area along the stalled front should see
PWATs in the 2.1 to 2.4 inch range. Second, the deep layer mean
winds are expected to decrease from around 15-25 knots today, to
around 10-15 knots by Friday afternoon, as an upper level ridge
axis builds in and reduces upper level winds. This should create an
enviornment that favors very high instantaneous rain rates and
slow-moving, backbuilding, and training clusters near the front.

This may be compensated by a weaker front and low-level
convergence, which would tend to favor clusters and line segments
that are more scattered across the region, rather than aligned in a
specific corridor. Nevertheless, there will still be localized
opportunities for periods of training convection that could result
in flash flooding. The chances (based on hi-res ensemble data) of
rain rates in excess of 2 inches per hour, and for 24-hour rainfall
totals in excess of 5 inches, are highest about 40mi either side of
a line from Birmingham AL, to Atlanta GA, to Aiken SC, to Myrtle
Beach SC, to Morehead City NC. In fact, the 12Z HREF even shows
potential for rain rates to exceed 3 inches per hour in this same
corridor, especially in South Carolina (neighborhood probabilities
as high as 30 percent in SC), so the potential for locally
significant flash flooding remains. An upgrade to Moderate Risk
cannot be ruled out if enough observational evidence and model
guidance suggests a corridor of sustained training convection is
becoming more likely.

...Ozarks and Lower Missouri Valley...

An MCS may be ongoing at the start of the period somewhere in the
vicinity of eastern Kansas and Missouri, near the nose of the low-
level jet. The biggest change with this outlook update was to trim
the Slight Risk out of eastern Missouri in collaboration with WFO
St. Louis. A limited number of models still progress heavy rainfall
further east in Missouri, but the consensus now points more clearly
to eastern Kansas and western and central Missouri. This also
aligns with a typical bias in modeled MCS activity in the central
Plains -- it often ends up further into the inflow than models
would suggest.

There is more uncertainty about what happens later in the forecast
period, from late Friday afternoon into Friday Night. Most hi-res
models suggest the convective cluster will progress southeast into
the Ozarks and potentially Mid-Mississippi Valley by 12Z Saturday.
However, they increasingly disagree on placement of the heaviest
rainfall, the convective evolution, and magnitude of the rainfall.

From a pattern recognition standpoint, there is some concern about
an increasingly favorable setup for a backbuilding MCS on Friday
Night. The low-level jet will veer to be more westerly, and the
20-30 knot low-level inflow will exceed the strength of the
increasingly weak 15-20 knot deep layer mean flow. In these
situations, you will occasionally see a convective line backbuild
into the unstable inflow for hours, on the periphery of the cold
pool. The 12Z HRRR is the model that shows this scenario most
clearly, and it generates a maximum of about 6 inches of rain in 6
hours near the AR-MO border late in the forecast period.
Conversely, other hi-res models show scattered convection that is
far less focused. To put it another way, the synoptic evolution
would favor potential for backbuilding storms on Friday Night, but
whether it happens will ultimately come down to specific convective
evolution from the Central Plains over the 24 hours prior, and
probably whether a stronger, more concentrated cold pool can
develop. This area will be monitored closely in future updates.

Lamers

Day 3
Valid 12Z Sat Jul 25 2026 - 12Z Sun Jul 26 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR THE EASTERN
CAROLINAS AND FOR PORTIONS OF NEW MEXICO...

...Southeast through the Tennessee Valley...

The outlook for the Southeast was left fairly consistent with the
previous version with a Slight Risk in the eastern Carolinas, and a
broad Marginal Risk over the rest of the region in the general
vicinity of the lingering front. A key uncertainty is the position
of the front, as earlier models, and still global model guidance is
positioned further north, while hi-res guidance beginning to come
into view for the forecast period (3km NAM, RRFS, REFS) places the
heaviest rain further south. For the time being, the Marginal Risk
was positioned in an intermediate location and close to the
corridor of greatest QPF on the WPC deterministic forecast.
However, the positioning of the risk area may continue to evolve in
future outlook updates. Overall, the environment will still be
favorable for high rain rates in the most organized thunderstorms,
with precipitable water values still expected to be above 2 inches.
However, the expectation of convective activity being more
scattered with an increasingly diffuse frontal boundary may keep
any flash flooding impacts isolated-scattered as well.

...Southwest...

The monsoon recharges and resets across the Four Corners region on
Saturday. A Slight Risk was introduced primarily across New Mexico
where available REFS, RRFS, and 3km NAM hi-res model guidance shows
localized heavy rainfall in the same area as elevated values
approaching 15 percent on the 12Z CSU machine learning ERO
probability guidance. The Slight Risk was concentrated more in
Central New Mexico as models show dry air advection into southern
New Mexico for much of the forecast period. North of that, in C/N
NM, precipitable water values will continue to be around or just
above the 90th percentile for July, and supportive of high rain
rates in any thunderstorms that can develop.

Lamers

Day 4 and Day 5

Valid 12Z Sun Jul 26 2026 - 12Z Tue Jul 28 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL ACROSS THE FOUR
CORNERS STATES, EXTENDING INTO THE CENTRAL PLAINS MONDAY AND OVER
THE GREAT LAKES, EXTENDING INTO THE NORTHEAST ON MONDAY...

...Four Corners States onto the Central Plains...

Monsoonal flow from the Desert Southwest to the central Rockies
continues into early next week. 12Z EC/GFS PW anomalies are
offset with the EC farther west (NM and CO) vs the GFS (over AZ/NV)
Maintaining Marginal Risks for now, but will continue to note that
shortwave impulses coming up from Mexico could enhance precip and
warrant a Slight Risk. Was able to remove part of southwest WY
given confidence on anomalous moisture being contained south from
the Uinta Mtns.

For Day 5 (12Z Mon-12Z Tue), the amendments to the Marginal Risk
were terrain based on the western side and farther onto the central
Plains (western Nebraska/Kansas) given output from the 12Z EC and
EC-AIFS. However, just like on Day 4, the EC is notably farther
east with anomalous moisture than the GFS. Either way,
convectively-aided shortwave activity should still traverse W-E
overtop the flattening mid- upper ridge into the central High
Plains.

...Upper Midwest-Great Lakes-Ohio Valley-Interior Northeast...

Global and AI guidance continue to show convectively-aided
shortwave activity riding down the top side of the upper ridge axis
over the western Dakota border in northwest flow. Guidance still shows
these ridge crawlers becoming a bit better organized through the
day 4-5 period, with an uptick in deep-layer QG forcing (Qs
convergence) and increasing low-level moisture transport. Broadened
the Marginal Risk on Day 4 to Duluth per the 12Z RRFS and into
northeast Iowa per the EC-AIFS. There is potential for this western
side to then proceed into Day 5/Monday in Illinois, but for now
the Day 5 Marginal Risk was expanded west through Indiana and
northern Kentucky. There is still notable spread in global guidance
for both of these days, but the threat for the NWly flow to become
parallel to any boundaries warrants the Marginal Risks given
enhanced moisture accompanying this activity.

Jackson/Hurley

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!_lgZU7_fCTSTolq1X47gRjwghWfXpQQpkBD-KQ-tpS9X8zRtxl56GA5y1TTfBhhDkSEllTpFy62Uoa13VrVPx_d_F3c$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!_lgZU7_fCTSTolq1X47gRjwghWfXpQQpkBD-KQ-tpS9X8zRtxl56GA5y1TTfBhhDkSEllTpFy62Uoa13VrVPJjYr87Q$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!_lgZU7_fCTSTolq1X47gRjwghWfXpQQpkBD-KQ-tpS9X8zRtxl56GA5y1TTfBhhDkSEllTpFy62Uoa13VrVPFGZtNAU$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Fri Jul 24 08:28:00 2026

FOUS30 KWBC 240827
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
427 AM EDT Fri Jul 24 2026

Day 1
Valid 12Z Fri Jul 24 2026 - 12Z Sat Jul 25 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE SOUTHEAST UNITED STATES...

...Southeast...

A stalled front will provide the focus for heavy to potentially
excessive rainfall across the Southeast United States with portions
of the Carolinas having the greatest risk for flash flooding.
Models continue to advertise a steady increase of moisture in the
850-500 mb layer, precipitable water values reaching 2.2 to 2.4
inches later today and deep-layer winds decreasing into the 10 to
15 knot range. This will all work to support slow moving
convection capable of producing very instantaneous heavy rainfall
rates and rainfall amounts this afternoon and tonight along a
weakening front which helps focus the activity. The 24/00Z HREF
and RRFS runs showed the potential for rainfall rates in excess of
3 inches per hour focused initially along coastal portions of South
Carolina and a small portion of adjacent North Carolina. So the
potential for locally significant flash flooding remains.

...Ozarks and Lower Missouri Valley...

Convection may be ongoing at the start of the period somewhere
across portions of eastern Kansas and Missouri. This activity
should taper off as the nocturnal low level jet tapers off.

There is more uncertainty about what happens later in the forecast
period, from late this afternoon into tonight, Most hi-res models
still suggest the convective cluster will progress southeast into
the Ozarks and potentially Mid- Mississippi Valley by 12Z Saturday.
However, they increasingly disagree on placement of the heaviest
rainfall, the convective evolution, and magnitude of the rainfall.

From a pattern recognition standpoint, there is some concern about
an increasingly favorable setup for a backbuilding MCS overnight. The
low-level jet will veer to be more westerly, and the 20-30 knot
low-level inflow will exceed the strength of the increasingly weak
15-20 knot deep layer mean flow. Synoptic evolution would favor
potential for backbuilding storms tonight, but that is contingent
on the convective evolution and whether a stronger, more
concentrated cold pool can develop.

Southwest US,,,
Moisture remains abundant in the Southwest US which should lead to
another round of convection developing in the afternoon and which
persists into the overnight hours. At this point...there appears
to be an isolated threat that rainfall rates or amounts lead to
flash flooding so a Marginal Risk was maintained.

Bann/Lamers

Day 2
Valid 12Z Sat Jul 25 2026 - 12Z Sun Jul 26 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR THE EASTERN
CAROLINAS AND FOR PORTIONS OF NEW MEXICO...

...Southeast through the Tennessee Valley...

The outlook for the Southeast was left fairly consistent with the
previous version with a Slight Risk in the eastern Carolinas, and a
broad Marginal Risk over the rest of the region in the general
vicinity of the lingering front. Hi-resolution guidance has become
more available and continues to place the heaviest rain farther
south. For the time being, the Marginal Risk was positioned in an
intermediate location and close to the corridor of greatest QPF and
along the axis of highest precipitable water values. This also
continued to align with the WPC deterministic forecast. However,
the positioning of the risk area may continue to evolve in future
outlook updates. Overall, the environment will still be favorable
for high rain rates in the most organized thunderstorms, with
precipitable water values still expected to be above 2 inches.

...Southwest...

The monsoon recharges and resets across the Four Corners region on
Saturday. A Slight Risk was introduced primarily across New Mexico
where available high resolution convective allowing models showed localized heavy rainfall in the same area as elevated values approaching 20
percent on the 12Z CSU machine learning ERO probability guidance.
There is some concern about the potential for a MCV from late
tonight/early Saturday morning to become a player which elevates
the potential for flash flooding later in the day on Saturday. This
would be in addition to the precipitable water values that will
continue to be around or just above the 90th percentile for July,
and supportive of high rain rates in any thunderstorms that can
develop.

Bann

Day 3
Valid 12Z Sun Jul 26 2026 - 12Z Mon Jul 27 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL ACROSS THE FOUR
CORNERS STATES, EXTENDING INTO THE CENTRAL PLAINS MONDAY AND OVER
THE GREAT LAKES, EXTENDING INTO THE NORTHEAST ON MONDAY...

...Four Corners States onto the Central Plains...

Monsoonal flow from the Desert Southwest to the central Rockies
continues into early next week. Precipitable water anomalies are
offset with the ECMWF farther west (New Mexico and Colorado as
compared to the GFS being located over Arizona and Nevada).
Maintained the Marginal Risks but will continue to note that
shortwave impulses coming up from Mexico could enhance precip and
warrant a Slight Risk. Was able to remove part of southwest WY
given confidence on anomalous moisture being contained south from
the Uinta Mtns.

...Upper Midwest-Great Lakes-Ohio Valley-Interior Northeast...

Global and AI guidance continue to show convectively-aided
shortwave activity riding down the top side of the upper ridge axis
over the western Dakota border in northwest flow. There was a bit
of a realignment made which focused on the shortwave crossing the
southern portion of Minnesota and Iowa moreso than the area farther
north. In doing so...the QPF tracks along a corridor of lower Flash
Flood Guidance that reaches 1.5 inches per 3 hours and tends to fit
the placement of maximum precipitable water values which peak at
or slightly greater than 1.75 inches. The convection should be
progressive enough to preclude the need for a Slight Risk at this
point.

Bann

Day 4 and Day 5

Valid 12Z Mon Jul 27 2026 - 12Z Wed Jul 29 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL MONDAY AND
TUESDAY ACROSS THE FOUR CORNERS STATES EXTENDING INTO THE CENTRAL
PLAINS, AND OVER THE EASTERN GREAT LAKES AND OHIO VALLEY EXTENDING
INTO THE NORTHEAST AND MID ATLANTIC...

...Four Corners States into the Central Plains...

Monsoonal flow from the Desert Southwest to the central Rockies and
central Plains continues into early next week. Based on the latest
(00Z) guidance, did not make many changes to yesterday's Day 5
Marginal Risk area. This also includes the latest ECENS/GEFS/CMCE
24 probabilities of 1-2+ inches in 24 hours.

For Day 5 (12Z Tue-12Z Wed), given the persistent pattern, the ERO
is essentially a carbon-copy of Day 4, with the eastern extension
across the Central Plains. This follows along with the boost in QPF
per the AIGFS and ECMWF AIFS, as both of these models show more
vigorous (convectively-induced or enhanced) shortwave activity
rounding overtop the mid/upper level ridge.

...Eastern Great Lakes-Ohio Valley-Interior Northeast...

Global and AI guidance continue to show convectively-aided
shortwave activity riding down the top side of the upper ridge axis
over the western Dakota border in northwest flow. Guidance still shows
these ridge crawlers becoming a bit better organized through the
day 4-5 period, with an uptick in deep-layer QG forcing (Qs convergence)
and increasing low-level moisture transport. By Day 5, strengthening
exit region forcing downwind of advancing upper level jet streak
will help amplify the longwave trough across the Great Lakes-OH
Valley and Northeast, with a decent surge in pre-frontal deep-layer
moisture as PWs climb between 1.75-2.00". Based on the QPF trends
from the global guidance (including AI), and given the progressive
forward speed of the embedded shortwaves, have essentially
propagated the Day 4 Marginal farther downstream into the Eastern
Seaboard from the Mid Atlantic to Northeast Tue into Wed. Given
the progressive nature of the synoptic features, relatively low
24hr probabilities of QPF>2" per the GEFS/CMCE/ECENS systems, and
current lackluster ECMWF EFI values, for now will start with a
broad Marginal Risk, though with the anticipation that at some
point (once in the short range) we may be able to target areas with
a notably higher ERO risk (i.e. Slight).

Hurley

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!_MnUzO-Zsush1G9c2bSfZxCFC6UZO03N5GU7SkvmEK_rlXVZTi8yv_p8nLjwy2SHks9F_N-G1xoXb10TbNpLtNjbfss$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!_MnUzO-Zsush1G9c2bSfZxCFC6UZO03N5GU7SkvmEK_rlXVZTi8yv_p8nLjwy2SHks9F_N-G1xoXb10TbNpLVP2VgAs$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!_MnUzO-Zsush1G9c2bSfZxCFC6UZO03N5GU7SkvmEK_rlXVZTi8yv_p8nLjwy2SHks9F_N-G1xoXb10TbNpLP-rlCXs$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Fri Jul 24 15:55:38 2026

FOUS30 KWBC 241554
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1154 AM EDT Fri Jul 24 2026

Day 1
Valid 16Z Fri Jul 24 2026 - 12Z Sat Jul 25 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE SOUTHEAST UNITED STATES...

...Southeast...

A stalled front in the vicinity, draped across northern Georgia
toward coastal North Carolina, will be the focus for scattered to
numerous showers and thunderstorms during the period. Anomalous
moisture, characterized by PWs in the 2.0-2.4 inch range, combined
with building instability (mainly along the immediate coast), will
support high rain rates. The latest guidance points toward
potential for instantaneous rain rates in excess of 2-3"/hr,
particularly from interior South Carolina toward the coast as well
as portions of southeastern NC. Total amounts during the period may
exceed 3-5 inches in localized areas. No significant changes were
made to the Moderate Risk area, which covers the threat well for
scattered to numerous instances of flash floods, some of which
could be significant.

...Ozarks and Lower Missouri Valley...

Convection may be ongoing at the start of the period somewhere
across portions of eastern Kansas and Missouri. This activity
should taper off as the nocturnal low level jet tapers off.

There is more uncertainty about what happens later in the forecast
period, from late this afternoon into tonight, Most hi-res models
still suggest the convective cluster will progress southeast into
the Ozarks and potentially Mid- Mississippi Valley by 12Z Saturday.
However, they increasingly disagree on placement of the heaviest
rainfall, the convective evolution, and magnitude of the rainfall.

From a pattern recognition standpoint, there is some concern about
an increasingly favorable setup for a backbuilding MCS overnight. The
low-level jet will veer to be more westerly, and the 20-30 knot
low-level inflow will exceed the strength of the increasingly weak
15-20 knot deep layer mean flow. Synoptic evolution would favor
potential for backbuilding storms tonight, but that is contingent
on the convective evolution and whether a stronger, more
concentrated cold pool can develop.

...Southwest US...
Another moisture abundant day in the southwest U.S. will lead to
another round of isolated to widely scattered convection peaking
this afternoon and lingering into the early overnight hours. No
changes needed to the risk areas, with the threat covered well with
the Marginal Risk.

...Northern Minnesota...
A localized flash flood threat exists with an approaching front
interacting with somewhat elevated moisture in place. The 12Z
guidance points toward a stripe of locally heavy rainfall,
potentially 1-3", across northern Minnesota, mainly interior areas.
A Marginal Risk was introduced.

Taylor/Bann/Lamers

Day 2
Valid 12Z Sat Jul 25 2026 - 12Z Sun Jul 26 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR THE EASTERN
CAROLINAS AND FOR PORTIONS OF NEW MEXICO...

...Southeast through the Tennessee Valley...

The outlook for the Southeast was left fairly consistent with the
previous version with a Slight Risk in the eastern Carolinas, and a
broad Marginal Risk over the rest of the region in the general
vicinity of the lingering front. Hi-resolution guidance has become
more available and continues to place the heaviest rain farther
south. For the time being, the Marginal Risk was positioned in an
intermediate location and close to the corridor of greatest QPF and
along the axis of highest precipitable water values. This also
continued to align with the WPC deterministic forecast. However,
the positioning of the risk area may continue to evolve in future
outlook updates. Overall, the environment will still be favorable
for high rain rates in the most organized thunderstorms, with
precipitable water values still expected to be above 2 inches.

...Southwest...

The monsoon recharges and resets across the Four Corners region on
Saturday. A Slight Risk was introduced primarily across New Mexico
where available high resolution convective allowing models showed localized heavy rainfall in the same area as elevated values approaching 20
percent on the 12Z CSU machine learning ERO probability guidance.
There is some concern about the potential for a MCV from late
tonight/early Saturday morning to become a player which elevates
the potential for flash flooding later in the day on Saturday. This
would be in addition to the precipitable water values that will
continue to be around or just above the 90th percentile for July,
and supportive of high rain rates in any thunderstorms that can
develop.

Bann

Day 3
Valid 12Z Sun Jul 26 2026 - 12Z Mon Jul 27 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL ACROSS THE FOUR
CORNERS STATES, EXTENDING INTO THE CENTRAL PLAINS MONDAY AND OVER
THE GREAT LAKES, EXTENDING INTO THE NORTHEAST ON MONDAY...

...Four Corners States onto the Central Plains...

Monsoonal flow from the Desert Southwest to the central Rockies
continues into early next week. Precipitable water anomalies are
offset with the ECMWF farther west (New Mexico and Colorado as
compared to the GFS being located over Arizona and Nevada).
Maintained the Marginal Risks but will continue to note that
shortwave impulses coming up from Mexico could enhance precip and
warrant a Slight Risk. Was able to remove part of southwest WY
given confidence on anomalous moisture being contained south from
the Uinta Mtns.

...Upper Midwest-Great Lakes-Ohio Valley-Interior Northeast...

Global and AI guidance continue to show convectively-aided
shortwave activity riding down the top side of the upper ridge axis
over the western Dakota border in northwest flow. There was a bit
of a realignment made which focused on the shortwave crossing the
southern portion of Minnesota and Iowa moreso than the area farther
north. In doing so...the QPF tracks along a corridor of lower Flash
Flood Guidance that reaches 1.5 inches per 3 hours and tends to fit
the placement of maximum precipitable water values which peak at
or slightly greater than 1.75 inches. The convection should be
progressive enough to preclude the need for a Slight Risk at this
point.

Bann

Day 4 and Day 5

Valid 12Z Mon Jul 27 2026 - 12Z Wed Jul 29 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL MONDAY AND
TUESDAY ACROSS THE FOUR CORNERS STATES EXTENDING INTO THE CENTRAL
PLAINS, AND OVER THE EASTERN GREAT LAKES AND OHIO VALLEY EXTENDING
INTO THE NORTHEAST AND MID ATLANTIC...

...Four Corners States into the Central Plains...

Monsoonal flow from the Desert Southwest to the central Rockies and
central Plains continues into early next week. Based on the latest
(00Z) guidance, did not make many changes to yesterday's Day 5
Marginal Risk area. This also includes the latest ECENS/GEFS/CMCE
24 probabilities of 1-2+ inches in 24 hours.

For Day 5 (12Z Tue-12Z Wed), given the persistent pattern, the ERO
is essentially a carbon-copy of Day 4, with the eastern extension
across the Central Plains. This follows along with the boost in QPF
per the AIGFS and ECMWF AIFS, as both of these models show more
vigorous (convectively-induced or enhanced) shortwave activity
rounding overtop the mid/upper level ridge.

...Eastern Great Lakes-Ohio Valley-Interior Northeast...

Global and AI guidance continue to show convectively-aided
shortwave activity riding down the top side of the upper ridge axis
over the western Dakota border in northwest flow. Guidance still shows
these ridge crawlers becoming a bit better organized through the
day 4-5 period, with an uptick in deep-layer QG forcing (Qs convergence)
and increasing low-level moisture transport. By Day 5, strengthening
exit region forcing downwind of advancing upper level jet streak
will help amplify the longwave trough across the Great Lakes-OH
Valley and Northeast, with a decent surge in pre-frontal deep-layer
moisture as PWs climb between 1.75-2.00". Based on the QPF trends
from the global guidance (including AI), and given the progressive
forward speed of the embedded shortwaves, have essentially
propagated the Day 4 Marginal farther downstream into the Eastern
Seaboard from the Mid Atlantic to Northeast Tue into Wed. Given
the progressive nature of the synoptic features, relatively low
24hr probabilities of QPF>2" per the GEFS/CMCE/ECENS systems, and
current lackluster ECMWF EFI values, for now will start with a
broad Marginal Risk, though with the anticipation that at some
point (once in the short range) we may be able to target areas with
a notably higher ERO risk (i.e. Slight).

Hurley

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!5PAa5GRX3LT981I0NinoLt4c1fPZVL8C9jEDTecYrrQv8xZtesq5gNjg0YvJ67WwKCKfhWrBFDQqWiv3iRKu-TDrYhY$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!5PAa5GRX3LT981I0NinoLt4c1fPZVL8C9jEDTecYrrQv8xZtesq5gNjg0YvJ67WwKCKfhWrBFDQqWiv3iRKuNYCAZhI$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!5PAa5GRX3LT981I0NinoLt4c1fPZVL8C9jEDTecYrrQv8xZtesq5gNjg0YvJ67WwKCKfhWrBFDQqWiv3iRKuFbC0au4$

$$

= = =
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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Fri Jul 24 19:59:46 2026

FOUS30 KWBC 241959
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
359 PM EDT Fri Jul 24 2026

Day 1
Valid 16Z Fri Jul 24 2026 - 12Z Sat Jul 25 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE SOUTHEAST UNITED STATES...

...Southeast...

A stalled front in the vicinity, draped across northern Georgia
toward coastal North Carolina, will be the focus for scattered to
numerous showers and thunderstorms during the period. Anomalous
moisture, characterized by PWs in the 2.0-2.4 inch range, combined
with building instability (mainly along the immediate coast), will
support high rain rates. The latest guidance points toward
potential for instantaneous rain rates in excess of 2-3"/hr,
particularly from interior South Carolina toward the coast as well
as portions of southeastern NC. Total amounts during the period may
exceed 3-5 inches in localized areas. No significant changes were
made to the Moderate Risk area, which covers the threat well for
scattered to numerous instances of flash floods, some of which
could be significant.

...Ozarks and Lower Missouri Valley...

Convection may be ongoing at the start of the period somewhere
across portions of eastern Kansas and Missouri. This activity
should taper off as the nocturnal low level jet tapers off.

There is more uncertainty about what happens later in the forecast
period, from late this afternoon into tonight, Most hi-res models
still suggest the convective cluster will progress southeast into
the Ozarks and potentially Mid- Mississippi Valley by 12Z Saturday.
However, they increasingly disagree on placement of the heaviest
rainfall, the convective evolution, and magnitude of the rainfall.

From a pattern recognition standpoint, there is some concern about
an increasingly favorable setup for a backbuilding MCS overnight. The
low-level jet will veer to be more westerly, and the 20-30 knot
low-level inflow will exceed the strength of the increasingly weak
15-20 knot deep layer mean flow. Synoptic evolution would favor
potential for backbuilding storms tonight, but that is contingent
on the convective evolution and whether a stronger, more
concentrated cold pool can develop.

...Southwest US...
Another moisture abundant day in the southwest U.S. will lead to
another round of isolated to widely scattered convection peaking
this afternoon and lingering into the early overnight hours. No
changes needed to the risk areas, with the threat covered well with
the Marginal Risk.

...Northern Minnesota...
A localized flash flood threat exists with an approaching front
interacting with somewhat elevated moisture in place. The 12Z
guidance points toward a stripe of locally heavy rainfall,
potentially 1-3", across northern Minnesota, mainly interior areas.
A Marginal Risk was introduced.

Taylor/Bann/Lamers

Day 2
Valid 12Z Sat Jul 25 2026 - 12Z Sun Jul 26 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR THE EASTERN CAROLINAS...PORTIONS OF ARKANSAS...AND THE SOUTHWEST...

...Southeast through the Tennessee Valley...

Along and in the vicinity of the stalled frontal boundary,
plentiful moisture will be in place. The main focus will be across
the eastern Carolinas where guidance continues to point toward
heavy rainfall continuing from the day one period. Hi-res guidance
points to localized 2-4 inch totals with higher rain rates likely
as well. The Slight Risk was maintained along the coastal areas for
scattered instances of flash flooding.

Over portions of Arkansas, the 12 UTC guidance today showed
increasing agreement with a complex of thunderstorms developing
Saturday with slow moving or repeating rounds of heavy rainfall.
Across the board, there was a general uptick in the QPF totals with
the HREF neighborhood probabilities for 3-5 inches above 80
percent. HREF and REFS probs also have trended higher for hourly
totals in excess of 2-3" at times 12Z-18Z. Some concern for some
very localized extreme rainfall given slow storm motions. For these
reasons, a Slight Risk was introduced.

...Southwest...

The monsoon will recharge/reset across the Four Corners on Saturday
with an uptick in coverage and intensity of rainfall across the
region. QPF amounts did trend up overall and PW values are above
the 90th percentile. Guidance points toward a MCV in the vicinity
becoming a key player in enhancing the rainfall and leading to
greater/higher rain rates. The Slight Risk was maintained with some
adjustments to the latest QPF and across west-central NM, the risk
does lean toward the higher end of the Slight Risk probability
range.

Taylor/Bann

Day 3
Valid 12Z Sun Jul 26 2026 - 12Z Mon Jul 27 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL ACROSS THE FOUR
CORNERS REGION...UPPER MIDWEST...AND PORTIONS OF FLORIDA...

...Four Corners States onto the Central Plains...

Monsoonal flow from the Desert Southwest to the central Rockies
continues into early next week. Precipitable water values and
available instability will again support isolated to widely
scattered thunderstorms capable of producing intense rain rates
capable of producing flash flooding. A broad Marginal Risk was
maintained this cycle, but future forecasts may need an embedded
Slight Risk once predictability increases.

...Upper Midwest-Great Lakes-Ohio Valley-Interior Northeast...

Global and AI guidance continue to show convectively-aided
shortwave activity riding down the top side of the upper ridge axis
over the western Dakota border in northwest flow. Some spatial
uncertainty in where the heaviest rainfall may occur with a slight
nudge toward southern Wisconsin this cycle. As a result, the
Marginal Risk was adjusted some to account for this, with an
extension to the east over portions of WI/IL. Otherwise, the
inherited risk area is in good shape.

Taylor/Bann

Day 4 and Day 5

Valid 12Z Mon Jul 27 2026 - 12Z Wed Jul 29 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL MONDAY AND
TUESDAY ACROSS THE FOUR CORNERS STATES EXTENDING INTO THE CENTRAL
PLAINS, AND OVER THE EASTERN GREAT LAKES AND OHIO VALLEY EXTENDING
INTO THE NORTHEAST AND MID ATLANTIC...

...Four Corners States into the Central Plains...

Monsoonal flow from the Desert Southwest to the central Rockies and
central Plains continues into early next week. Based on the latest
(00Z) guidance, did not make many changes to yesterday's Day 5
Marginal Risk area. This also includes the latest ECENS/GEFS/CMCE
24 probabilities of 1-2+ inches in 24 hours.

For Day 5 (12Z Tue-12Z Wed), given the persistent pattern, the ERO
is essentially a carbon-copy of Day 4, with the eastern extension
across the Central Plains. This follows along with the boost in QPF
per the AIGFS and ECMWF AIFS, as both of these models show more
vigorous (convectively-induced or enhanced) shortwave activity
rounding overtop the mid/upper level ridge.

...Eastern Great Lakes-Ohio Valley-Interior Northeast...

Global and AI guidance continue to show convectively-aided
shortwave activity riding down the top side of the upper ridge axis
over the western Dakota border in northwest flow. Guidance still shows
these ridge crawlers becoming a bit better organized through the
day 4-5 period, with an uptick in deep-layer QG forcing (Qs convergence)
and increasing low-level moisture transport. By Day 5, strengthening
exit region forcing downwind of advancing upper level jet streak
will help amplify the longwave trough across the Great Lakes-OH
Valley and Northeast, with a decent surge in pre-frontal deep-layer
moisture as PWs climb between 1.75-2.00". Based on the QPF trends
from the global guidance (including AI), and given the progressive
forward speed of the embedded shortwaves, have essentially
propagated the Day 4 Marginal farther downstream into the Eastern
Seaboard from the Mid Atlantic to Northeast Tue into Wed. Given
the progressive nature of the synoptic features, relatively low
24hr probabilities of QPF>2" per the GEFS/CMCE/ECENS systems, and
current lackluster ECMWF EFI values, for now will start with a
broad Marginal Risk, though with the anticipation that at some
point (once in the short range) we may be able to target areas with
a notably higher ERO risk (i.e. Slight).

Hurley

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!_4WN6LOoWg8gZ_DoTf8-O4rkntjZbHJ-kr5803se9YnM5QhgmrJPljW5nHgfiLq0LOJbunnmDn-BOnww0EVGNhwsoqo$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!_4WN6LOoWg8gZ_DoTf8-O4rkntjZbHJ-kr5803se9YnM5QhgmrJPljW5nHgfiLq0LOJbunnmDn-BOnww0EVGrDOpEss$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!_4WN6LOoWg8gZ_DoTf8-O4rkntjZbHJ-kr5803se9YnM5QhgmrJPljW5nHgfiLq0LOJbunnmDn-BOnww0EVG1XZdSpM$

$$

= = =
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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Fri Jul 24 20:28:48 2026

FOUS30 KWBC 242028
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
428 PM EDT Fri Jul 24 2026

Day 1
Valid 16Z Fri Jul 24 2026 - 12Z Sat Jul 25 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE SOUTHEAST UNITED STATES...

...Southeast...

A stalled front in the vicinity, draped across northern Georgia
toward coastal North Carolina, will be the focus for scattered to
numerous showers and thunderstorms during the period. Anomalous
moisture, characterized by PWs in the 2.0-2.4 inch range, combined
with building instability (mainly along the immediate coast), will
support high rain rates. The latest guidance points toward
potential for instantaneous rain rates in excess of 2-3"/hr,
particularly from interior South Carolina toward the coast as well
as portions of southeastern NC. Total amounts during the period may
exceed 3-5 inches in localized areas. No significant changes were
made to the Moderate Risk area, which covers the threat well for
scattered to numerous instances of flash floods, some of which
could be significant.

...Ozarks and Lower Missouri Valley...

Convection may be ongoing at the start of the period somewhere
across portions of eastern Kansas and Missouri. This activity
should taper off as the nocturnal low level jet tapers off.

There is more uncertainty about what happens later in the forecast
period, from late this afternoon into tonight, Most hi-res models
still suggest the convective cluster will progress southeast into
the Ozarks and potentially Mid- Mississippi Valley by 12Z Saturday.
However, they increasingly disagree on placement of the heaviest
rainfall, the convective evolution, and magnitude of the rainfall.

From a pattern recognition standpoint, there is some concern about
an increasingly favorable setup for a backbuilding MCS overnight. The
low-level jet will veer to be more westerly, and the 20-30 knot
low-level inflow will exceed the strength of the increasingly weak
15-20 knot deep layer mean flow. Synoptic evolution would favor
potential for backbuilding storms tonight, but that is contingent
on the convective evolution and whether a stronger, more
concentrated cold pool can develop.

...Southwest US...
Another moisture abundant day in the southwest U.S. will lead to
another round of isolated to widely scattered convection peaking
this afternoon and lingering into the early overnight hours. No
changes needed to the risk areas, with the threat covered well with
the Marginal Risk.

...Northern Minnesota...
A localized flash flood threat exists with an approaching front
interacting with somewhat elevated moisture in place. The 12Z
guidance points toward a stripe of locally heavy rainfall,
potentially 1-3", across northern Minnesota, mainly interior areas.
A Marginal Risk was introduced.

Taylor/Bann/Lamers

Day 2
Valid 12Z Sat Jul 25 2026 - 12Z Sun Jul 26 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR THE EASTERN CAROLINAS...PORTIONS OF ARKANSAS...AND THE SOUTHWEST...

...Southeast through the Tennessee Valley...

Along and in the vicinity of the stalled frontal boundary,
plentiful moisture will be in place. The main focus will be across
the eastern Carolinas where guidance continues to point toward
heavy rainfall continuing from the day one period. Hi-res guidance
points to localized 2-4 inch totals with higher rain rates likely
as well. The Slight Risk was maintained along the coastal areas for
scattered instances of flash flooding.

Over portions of Arkansas, the 12 UTC guidance today showed
increasing agreement with a complex of thunderstorms developing
Saturday with slow moving or repeating rounds of heavy rainfall.
Across the board, there was a general uptick in the QPF totals with
the HREF neighborhood probabilities for 3-5 inches above 80
percent. HREF and REFS probs also have trended higher for hourly
totals in excess of 2-3" at times 12Z-18Z. Some concern for some
very localized extreme rainfall given slow storm motions. For these
reasons, a Slight Risk was introduced.

...Southwest...

The monsoon will recharge/reset across the Four Corners on Saturday
with an uptick in coverage and intensity of rainfall across the
region. QPF amounts did trend up overall and PW values are above
the 90th percentile. Guidance points toward a MCV in the vicinity
becoming a key player in enhancing the rainfall and leading to
greater/higher rain rates. The Slight Risk was maintained with some
adjustments to the latest QPF and across west-central NM, the risk
does lean toward the higher end of the Slight Risk probability
range.

Taylor/Bann

Day 3
Valid 12Z Sun Jul 26 2026 - 12Z Mon Jul 27 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL ACROSS THE FOUR
CORNERS REGION...UPPER MIDWEST...AND PORTIONS OF FLORIDA...

...Four Corners States onto the Central Plains...

Monsoonal flow from the Desert Southwest to the central Rockies
continues into early next week. Precipitable water values and
available instability will again support isolated to widely
scattered thunderstorms capable of producing intense rain rates
capable of producing flash flooding. A broad Marginal Risk was
maintained this cycle, but future forecasts may need an embedded
Slight Risk once predictability increases.

...Upper Midwest-Great Lakes-Ohio Valley-Interior Northeast...

Global and AI guidance continue to show convectively-aided
shortwave activity riding down the top side of the upper ridge axis
over the western Dakota border in northwest flow. Some spatial
uncertainty in where the heaviest rainfall may occur with a slight
nudge toward southern Wisconsin this cycle. As a result, the
Marginal Risk was adjusted some to account for this, with an
extension to the east over portions of WI/IL. Otherwise, the
inherited risk area is in good shape.

Taylor/Bann

Day 4 and Day 5

Valid 12Z Mon Jul 27 2026 - 12Z Wed Jul 29 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL MONDAY AND
TUESDAY ACROSS THE FOUR CORNERS STATES EXTENDING INTO THE CENTRAL
PLAINS, AND THE GREAT LAKES AND OHIO VALLEY ON MONDAY SHIFTING TO
THE NORTHEAST AND MID-ATLANTIC FOR TUESDAY...

...Four Corners States into the Central Plains...

Monsoonal flow bringing elevated moisture over the Desert
Southwest through the central Rockies continues with a southward
trend in the upper high center directing activity back onto the
central Plains early next week. Main edits for both Days 4/5 were
to include in the Marginal Risk the typical terrain on the western
end in northwest Arizona and Southwest Utah as well as farther
downstream over the central Plains, especially for Day 5. EC-AIFS
QPF and ECMWF PW anomaly plots continue to prove helpful in
highlighting areas of increased concern (including coverage for the
central Plains).

The more suppressed ridge will allow greater shortwave passage over
the top/across the Rockies.

...Great Lakes, Ohio Valley, Mid-Atlantic, and Northeast...

The focus of shortwave activity rolling off the High Plains ridge
axis is perhaps best depicted by the 12Z ECMWF as tracking over
northern MN on Monday and developing into a low pressure system
downstream of the Great Lakes on Tuesday. This low would provide
the forcing for heavier rain and a potential Slight Risk over the
Northeast, so that will need to be monitored.

Otherwise, it's northwest flow progressive convective activity from
the Great Lakes tracking to the Northeast with training where the
flow is parallel to boundaries. The Marginal Risk for Day 4 was
expanded back west over Chicago and Indiana while the Day 5 was
trimmed a bit to hone in on the Mid-Atlantic through Northeast
(perhaps not as much of Maine). The EC-AIFS proves helpful here too
with the positioning of the areas as well as the last 12 hours of
the 12Z RRFS/RDPS for the first half of Day 4.

Jackson

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!9XiiuJTHYDJ-ZyP6TIrsoJMvvlpKGujxXUn6U9rkR6Fvf-H45Eg5Ac3EzPhZQBbHF2km8oHwM4F_vcC9ZM-Ytq7qyTE$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!9XiiuJTHYDJ-ZyP6TIrsoJMvvlpKGujxXUn6U9rkR6Fvf-H45Eg5Ac3EzPhZQBbHF2km8oHwM4F_vcC9ZM-YiK7DNtY$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!9XiiuJTHYDJ-ZyP6TIrsoJMvvlpKGujxXUn6U9rkR6Fvf-H45Eg5Ac3EzPhZQBbHF2km8oHwM4F_vcC9ZM-Y2mieNQs$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Jul 25 00:53:24 2026

FOUS30 KWBC 250053
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
853 PM EDT Fri Jul 24 2026

Day 1
Valid 01Z Sat Jul 25 2026 - 12Z Sat Jul 25 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE SOUTHEAST UNITED STATES...

...Southeast...

Earlier activity along a stalled front has waned over coastal and
southern NC where the Moderate was dropped. South of the front in
southern SC down toward the Savannah area there remains a risk for
particularly heavy thunderstorms with 2-3"/hr rates where 2.2 to
2.4" PW remains with an instability gradient. Considerable flash
flooding is possible overnight through these areas.

Activity near/north of Atlanta has peaked with available
instability used there. The Slight Risk continues for southeast TN
where the RAP maintains instability along with areas across
northern MS/AL/GA where further activity may be few and far
between, but it is more sensitive from earlier activity with
persistent moisture pooling.

...Ozarks and Lower Missouri Valley...

Activity is light early this evening over MO/AR. However, the
presence of the front extending southeast from eastern KS down
through central AR by way of southwest MO where ample moisture is
pooled with instability along/west of the front and an increasing
low level jet should trigger scattered overnight flash flooding
concerns.

There remains increasing concern for a backbuilding MCS overnight
near this front and in particular over central to eastern Arkansas.
The low- level jet will veer to be more westerly, and the 20-30
knot low- level inflow will exceed the strength of the increasingly
weak 15-20 knot deep layer mean flow. Synoptic evolution favors
backbuilding storms tonight once a stronger, more concentrated
cold pool can develop. The Slight Risk was trimmed on the north
side where instability is lacking and expanded over southern AR
where HRRR continues to have late night heavy development that
lasts into Saturday (where a Day 2 Slight already exists).

...Southwest US...

For the 01Z update, the Marginal Risk was expanded south a bit with
some trimming on the north. Monsoonal flow continues across the
Four Corners states with an extension onto the southern Plains
through the Texas Panhandle. Nocturnal trends will take over soon
with widely scattered flash flood instances anticipated rest of
this evening.

...Northern Minnesota...

Energetic activity over northwestern MN continues to rapidly
develop this evening and tracking ESE. The combination of leading
supercells with discrete cells back toward the ND border in an
environment of +2 sigma PW and a strong instability gradient
warrants a Slight Risk downstream. Instability should continue to
wane near Lake Superior, so the Slight Risk is limited to inland.
Recent HRRRs have a decent handle on convection with 2"/hr rates,
so its output was used to keep the Slight Risk north of Duluth
proper.

Jackson

Day 2
Valid 12Z Sat Jul 25 2026 - 12Z Sun Jul 26 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR THE EASTERN CAROLINAS...PORTIONS OF ARKANSAS...AND THE SOUTHWEST...

...Southeast through the Tennessee Valley...

Along and in the vicinity of the stalled frontal boundary,
plentiful moisture will be in place. The main focus will be across
the eastern Carolinas where guidance continues to point toward
heavy rainfall continuing from the day one period. Hi-res guidance
points to localized 2-4 inch totals with higher rain rates likely
as well. The Slight Risk was maintained along the coastal areas for
scattered instances of flash flooding.

Over portions of Arkansas, the 12 UTC guidance today showed
increasing agreement with a complex of thunderstorms developing
Saturday with slow moving or repeating rounds of heavy rainfall.
Across the board, there was a general uptick in the QPF totals with
the HREF neighborhood probabilities for 3-5 inches above 80
percent. HREF and REFS probs also have trended higher for hourly
totals in excess of 2-3" at times 12Z-18Z. Some concern for some
very localized extreme rainfall given slow storm motions. For these
reasons, a Slight Risk was introduced.

...Southwest...

The monsoon will recharge/reset across the Four Corners on Saturday
with an uptick in coverage and intensity of rainfall across the
region. QPF amounts did trend up overall and PW values are above
the 90th percentile. Guidance points toward a MCV in the vicinity
becoming a key player in enhancing the rainfall and leading to
greater/higher rain rates. The Slight Risk was maintained with some
adjustments to the latest QPF and across west-central NM, the risk
does lean toward the higher end of the Slight Risk probability
range.

Taylor/Bann

Day 3
Valid 12Z Sun Jul 26 2026 - 12Z Mon Jul 27 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL ACROSS THE FOUR
CORNERS REGION...UPPER MIDWEST...AND PORTIONS OF FLORIDA...

...Four Corners States onto the Central Plains...

Monsoonal flow from the Desert Southwest to the central Rockies
continues into early next week. Precipitable water values and
available instability will again support isolated to widely
scattered thunderstorms capable of producing intense rain rates
capable of producing flash flooding. A broad Marginal Risk was
maintained this cycle, but future forecasts may need an embedded
Slight Risk once predictability increases.

...Upper Midwest-Great Lakes-Ohio Valley-Interior Northeast...

Global and AI guidance continue to show convectively-aided
shortwave activity riding down the top side of the upper ridge axis
over the western Dakota border in northwest flow. Some spatial
uncertainty in where the heaviest rainfall may occur with a slight
nudge toward southern Wisconsin this cycle. As a result, the
Marginal Risk was adjusted some to account for this, with an
extension to the east over portions of WI/IL. Otherwise, the
inherited risk area is in good shape.

Taylor/Bann

Day 4 and Day 5

Valid 12Z Mon Jul 27 2026 - 12Z Wed Jul 29 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL MONDAY AND
TUESDAY ACROSS THE FOUR CORNERS STATES EXTENDING INTO THE CENTRAL
PLAINS, AND THE GREAT LAKES AND OHIO VALLEY ON MONDAY SHIFTING TO
THE NORTHEAST AND MID-ATLANTIC FOR TUESDAY...

...Four Corners States into the Central Plains...

Monsoonal flow bringing elevated moisture over the Desert
Southwest through the central Rockies continues with a southward
trend in the upper high center directing activity back onto the
central Plains early next week. Main edits for both Days 4/5 were
to include in the Marginal Risk the typical terrain on the western
end in northwest Arizona and Southwest Utah as well as farther
downstream over the central Plains, especially for Day 5. EC-AIFS
QPF and ECMWF PW anomaly plots continue to prove helpful in
highlighting areas of increased concern (including coverage for the
central Plains).

The more suppressed ridge will allow greater shortwave passage over
the top/across the Rockies.

...Great Lakes, Ohio Valley, Mid-Atlantic, and Northeast...

The focus of shortwave activity rolling off the High Plains ridge
axis is perhaps best depicted by the 12Z ECMWF as tracking over
northern MN on Monday and developing into a low pressure system
downstream of the Great Lakes on Tuesday. This low would provide
the forcing for heavier rain and a potential Slight Risk over the
Northeast, so that will need to be monitored.

Otherwise, it's northwest flow progressive convective activity from
the Great Lakes tracking to the Northeast with training where the
flow is parallel to boundaries. The Marginal Risk for Day 4 was
expanded back west over Chicago and Indiana while the Day 5 was
trimmed a bit to hone in on the Mid-Atlantic through Northeast
(perhaps not as much of Maine). The EC-AIFS proves helpful here too
with the positioning of the areas as well as the last 12 hours of
the 12Z RRFS/RDPS for the first half of Day 4.

Jackson

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!8BlWH3XBHJQT15JJMRGd53ZSoZa9YLEjYjn_wdvPnkKM40aGKA5DBu8oaS_Qwn2J5k96l7ZoQ2tww1D7JW0f2MXrGes$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!8BlWH3XBHJQT15JJMRGd53ZSoZa9YLEjYjn_wdvPnkKM40aGKA5DBu8oaS_Qwn2J5k96l7ZoQ2tww1D7JW0fiBWHQOE$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!8BlWH3XBHJQT15JJMRGd53ZSoZa9YLEjYjn_wdvPnkKM40aGKA5DBu8oaS_Qwn2J5k96l7ZoQ2tww1D7JW0fogIzb8w$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Jul 25 08:29:22 2026

FOUS30 KWBC 250828
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
428 AM EDT Sat Jul 25 2026

Day 1
Valid 12Z Sat Jul 25 2026 - 12Z Sun Jul 26 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR THE EASTERN CAROLINAS...PORTIONS OF ARKANSAS...AND THE SOUTHWEST...

...Southeast through the Tennessee Valley...

Deep moisture will continue to pool along and near a stalled
frontal boundary, which leads to precipitable water values reaching
nearly 3 standardized anomalies above climatology for late July and
in excess of the 95th percentile of climatology extending eastward
from the Tennessee Valley to the Carolinas. Guidance from the
25/00Z model cycle continued to point to heavy rainfall potential.
Localized 2-4 inch totals with higher instantaneous rainfall rates
appear in this portion of the Slight Risk. Changes made to the
outlook areas were largely confined to the Carolinas and to ensure
that they capture the effects of shortwave energy crossing the area
later this afternoon and the lowering of mid- and upper-level
heights as the larger scale trough amplifies along the coast.

Over portions of Arkansas, the 25/00 UTC guidance backed away as
strongly and quickly as the previous run strongly and quickly
showed agreement concerning the potential for a heavy rainfall-
producing thunderstorm complex developing today. The HREF
neighborhood probabilities for 3-5 inches in 24 hours fell back to
35 percent or less ending at 12Z Sunday. The decrease was
comparable for hourly rainfall accumulations exceeding 2-3 inches
in an hour. Given the large magnitude of run to run
differences...the confidence to upgrade was gone. But the
ingredients for heavy rainfall rates and amounts remain present so
a Slight risk area was kept and realigned a bit to fit the HREF and
RRFS guidance.

...Southwest...

The monsoon will get re-invigorated across the Four Corners today
with an uptick in coverage and intensity of rainfall expected in
the region. QPF amounts did trend up overall and precipitable water
values still being forecast at or above the 90th percentile.
Convection developed in the overnight hours and guidance such as
the HRRR have picked up on an MCV in the vicinity that was
anticipated on Friday. It still appears that this becomes a key
player in enhancing the rainfall which leads to greater/higher
rain rates. Concern is heightened given the possibility that the
higher rainfall rates/amounts overlaps with areas which have
recently dealt with heavy rainfall and where soils will be less
capable of handling the influx of rain water. The Slight Risk was
maintained with some adjustments to the latest QPF and across west-
central NM, the risk remains skewed toward the higher end of the
Slight Risk probability range.

Bann/Taylor

Day 2
Valid 12Z Sun Jul 26 2026 - 12Z Mon Jul 27 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL ACROSS THE FOUR
CORNERS REGION...UPPER MIDWEST...AND PORTIONS OF FLORIDA...

...Four Corners States onto the Central Plains...

Monsoonal flow from the Desert Southwest to the central Rockies
continues into early next week. Precipitable water values and
available instability will again support isolated to widely
scattered thunderstorms capable of producing intense rain rates
capable of producing flash flooding. While future outlooks may need
to embed a Slight Risk, there was little in the way of consistency
in the details of the 25/00Z model cycle that helped define the
location of a Slight risk area.

...Upper Midwest-Great Lakes-Ohio Valley-Interior Northeast...

Global and AI guidance continue to show convectively-aided
shortwave activity riding down the top side of the upper ridge axis
over the western Dakota border in northwest flow. Any kind of a
mean QPF had too little QPF spread over a large area due to the
spread in QPF placement. A nudge towards Wisconsin made last
outlook still has some merit given where the axis of highest
precipitable water appears in the ECMWF and GFS. This can sometimes
signal a preferred track for storms that produce the heaviest
rainfall but concern is that a upper level convergence associated
with a broad arching anticyclonic flow at the jet level might
alter the location of convection. However...a Marginal risk
category was appropriate for the uncertainty and the ingredients
for heavy rainfall were present in the lower levels so only minor
modifications were made.

Bann/Taylor

Day 3
Valid 12Z Mon Jul 27 2026 - 12Z Tue Jul 28 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL MONDAY ACROSS
THE FOUR CORNERS STATES EXTENDING INTO THE CENTRAL PLAINS...

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS THE
CENTRAL AND EASTERN GREAT LAKES INTO THE OHIO VALLEY...

...Four Corners States into the Central Plains...

Elevated amounts of moisture will linger over the Four Corners
region given a persistent monsoon pattern...although guidance still
points to a gradual southward shift in the placement of the upper
high center. That high will be directing activity from the central
plains back toward the Intermountain region. Maintained a
Marginal risk area in/the typical terrain of western/northwest
Arizona and Southwest Utah and extending eastward as far as the far
western High Plains. Plots of ECMWF PW anomaly plots continue to
prove helpful in highlighting areas of increased concern.

...Great Lakes and Ohio Valley into the Northeast US...

Shortwave energy rounding the top of the High Plains high is
forecast to trek from Minnesota into parts of the Great Lakes by
the end of the day. Difluent flow ahead of the shortwave will
eventually lead to the development of a low pressure system late
in the period. This low is expected to help forcing for heavier
rainfall over the eastern Lakes/Ohio Valley. Given the progressive
convective activity...maintained the Marginal risk area and not
particularly close to upgrading with this outlook cycle.

Bann

Day 4 and Day 5

Valid 12Z Tue Jul 28 2026 - 12Z Thu Jul 30 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL ACROSS THE FOUR
CORNERS STATES EXTENDING INTO THE CENTRAL PLAINS, AND ACROSS THE
CENTRAL APPALACHIANS AND MID ATLANTIC TO THE NORTHEAST...

...Four Corners States into the Central Plains...

Monsoonal flow bringing elevated moisture over the Desert
Southwest through the central Rockies continues with a southward
trend in the upper high center directing activity back onto the
central Plains early next week. Areal extent appears to be more
limited on Day 5 per the guidance, including the latest EC-AIFS and
GFS and AIGFS, as the PW anomaly decreases a bit. The more
suppressed ridge will allow multiple mesoscale/convectively aided
shortwaves to push over the top/across the Rockies into the Plains.

...Central Appalachians-Mid Atlantic to the Northeast...

Upper level jet streak riding down the ridge on Tuesday (D4) will
lead to amplification of the longwave trough across the Eastern
U.S. by the middle-later part of next week. Increasing deep-layer
forcing ahead of this amplifying trough and strengthening surface
front will coincide with the uptick in pre-trough/pre-frontal
low-level theta-e advection, as the PW anomaly expands across the
Eastern Seaboard. Whenever favorable (typical) warm-season
thermodynamics (deep-layer instability and moisture) are present
ahead of a more robust, cooler-season trough with strong deep-
layer shear, chances for more widespread convection are much
higher. For now, will maintain a Marginal Risk in the Days 4-5 ERO
because the guidance continues to move the front through fairly
quickly, with a fairly quick transition to strong negative theta-e
advection behind it. Over the weekend and early next week we will
reassess the need for a targeted Slight Risk, especially once the
event moves into the high res (CAM) windows.

Hurley

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!7OEQQdXbY1YnrPBxwHBDNkYlSKUznthHrwB6j5B4NBsOn_IsG3soOosqtNexY2noyMAKKLcYEkSq7k0cOZ-f70PF54Q$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!7OEQQdXbY1YnrPBxwHBDNkYlSKUznthHrwB6j5B4NBsOn_IsG3soOosqtNexY2noyMAKKLcYEkSq7k0cOZ-flca90Ks$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!7OEQQdXbY1YnrPBxwHBDNkYlSKUznthHrwB6j5B4NBsOn_IsG3soOosqtNexY2noyMAKKLcYEkSq7k0cOZ-fxBHgeAM$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Jul 25 15:56:38 2026

FOUS30 KWBC 251556
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1156 AM EDT Sat Jul 25 2026

Day 1
Valid 16Z Sat Jul 25 2026 - 12Z Sun Jul 26 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR THE EASTERN
CAROLINAS AND THE SOUTHWEST...

...Southeast through the Lower Mississippi and Tennessee Valleys...

Deep moisture will continue to pool along and near a stalled
frontal boundary, which leads to precipitable water values reaching
nearly 3 standardized anomalies above climatology for late July
and in excess of the 95th percentile of climatology extending
eastward from the Lower Mississippi and Tennessee Valleys to the
Carolinas. Recent CAMs continue to point to heavy rainfall
potential, with localized 2-4 inch totals with higher instantaneous
rainfall rates, especially in the eastern Carolinas where the
Slight Risk remains. Refer to MPD 846 for more on the threat into
this afternoon. Trimmed off the northern side of the Slight given
less instability to the north of the front in this issuance.
However, did expand the Marginal northward a bit farther west to
cover the southern Appalachians, where localized convection could
be present this evening and tonight over areas with wetter
antecedent conditions and lower FFG.

Farther west, recent guidance remains less enthusiastic compared
to a day ago regarding heavy rainfall in and around Arkansas. With
the 00Z and 12Z CAM/HREF cycles both laying off on heavy rain, felt
confident enough to remove the Slight Risk there. The 12Z HREF
does show some 30-40 percent probabilities of QPF exceeding FFG
near the Mississippi/western Tennessee border that could be a
relatively higher risk, but with too low confidence in impacts to
upgrade to a Slight there.

Scattered thunderstorms across Florida could also cause localized
heavy rain, but currently consider that to be sub-Marginal as EAS
probabilities of exceeding 2 inches is only around 10 percent, and
over the Everglades rather than the more sensitive urban corridor.

...Southwest...

The monsoon will get re-invigorated across the Four Corners today
with an uptick in coverage and intensity of rainfall expected in
the region. Instability could be 1000-2000 J/kg while precipitable
water values are forecast to be above the 90th percentile. An MCV
in the vicinity could become a key player in enhancing the rainfall
which leads to greater/higher rain rates. Concern is heightened
given the possibility that the higher rainfall rates/amounts
overlaps with areas which have recently dealt with heavy rainfall
and where soils will be less capable of handling the influx of rain
water. The Marginal and Slight Risks still look on track and were
adjusted only minimally from the previous issuance.

Tate/Bann

Day 2
Valid 12Z Sun Jul 26 2026 - 12Z Mon Jul 27 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL ACROSS THE FOUR
CORNERS REGION...UPPER MIDWEST...AND PORTIONS OF FLORIDA...

...Four Corners States onto the Central Plains...

Monsoonal flow from the Desert Southwest to the central Rockies
continues into early next week. Precipitable water values and
available instability will again support isolated to widely
scattered thunderstorms capable of producing intense rain rates
capable of producing flash flooding. While future outlooks may need
to embed a Slight Risk, there was little in the way of consistency
in the details of the 25/00Z model cycle that helped define the
location of a Slight risk area.

...Upper Midwest-Great Lakes-Ohio Valley-Interior Northeast...

Global and AI guidance continue to show convectively-aided
shortwave activity riding down the top side of the upper ridge axis
over the western Dakota border in northwest flow. Any kind of a
mean QPF had too little QPF spread over a large area due to the
spread in QPF placement. A nudge towards Wisconsin made last
outlook still has some merit given where the axis of highest
precipitable water appears in the ECMWF and GFS. This can sometimes
signal a preferred track for storms that produce the heaviest
rainfall but concern is that a upper level convergence associated
with a broad arching anticyclonic flow at the jet level might
alter the location of convection. However...a Marginal risk
category was appropriate for the uncertainty and the ingredients
for heavy rainfall were present in the lower levels so only minor
modifications were made.

Bann/Taylor

Day 3
Valid 12Z Mon Jul 27 2026 - 12Z Tue Jul 28 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL MONDAY ACROSS
THE FOUR CORNERS STATES EXTENDING INTO THE CENTRAL PLAINS...

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS THE
CENTRAL AND EASTERN GREAT LAKES INTO THE OHIO VALLEY...

...Four Corners States into the Central Plains...

Elevated amounts of moisture will linger over the Four Corners
region given a persistent monsoon pattern...although guidance still
points to a gradual southward shift in the placement of the upper
high center. That high will be directing activity from the central
plains back toward the Intermountain region. Maintained a
Marginal risk area in/the typical terrain of western/northwest
Arizona and Southwest Utah and extending eastward as far as the far
western High Plains. Plots of ECMWF PW anomaly plots continue to
prove helpful in highlighting areas of increased concern.

...Great Lakes and Ohio Valley into the Northeast US...

Shortwave energy rounding the top of the High Plains high is
forecast to trek from Minnesota into parts of the Great Lakes by
the end of the day. Difluent flow ahead of the shortwave will
eventually lead to the development of a low pressure system late
in the period. This low is expected to help forcing for heavier
rainfall over the eastern Lakes/Ohio Valley. Given the progressive
convective activity...maintained the Marginal risk area and not
particularly close to upgrading with this outlook cycle.

Bann

Day 4 and Day 5

Valid 12Z Tue Jul 28 2026 - 12Z Thu Jul 30 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL ACROSS THE FOUR
CORNERS STATES EXTENDING INTO THE CENTRAL PLAINS, AND ACROSS THE
CENTRAL APPALACHIANS AND MID ATLANTIC TO THE NORTHEAST...

...Four Corners States into the Central Plains...

Monsoonal flow bringing elevated moisture over the Desert
Southwest through the central Rockies continues with a southward
trend in the upper high center directing activity back onto the
central Plains early next week. Areal extent appears to be more
limited on Day 5 per the guidance, including the latest EC-AIFS and
GFS and AIGFS, as the PW anomaly decreases a bit. The more
suppressed ridge will allow multiple mesoscale/convectively aided
shortwaves to push over the top/across the Rockies into the Plains.

...Central Appalachians-Mid Atlantic to the Northeast...

Upper level jet streak riding down the ridge on Tuesday (D4) will
lead to amplification of the longwave trough across the Eastern
U.S. by the middle-later part of next week. Increasing deep-layer
forcing ahead of this amplifying trough and strengthening surface
front will coincide with the uptick in pre-trough/pre-frontal
low-level theta-e advection, as the PW anomaly expands across the
Eastern Seaboard. Whenever favorable (typical) warm-season
thermodynamics (deep-layer instability and moisture) are present
ahead of a more robust, cooler-season trough with strong deep-
layer shear, chances for more widespread convection are much
higher. For now, will maintain a Marginal Risk in the Days 4-5 ERO
because the guidance continues to move the front through fairly
quickly, with a fairly quick transition to strong negative theta-e
advection behind it. Over the weekend and early next week we will
reassess the need for a targeted Slight Risk, especially once the
event moves into the high res (CAM) windows.

Hurley

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!5oiSwqmtCLR8sv1y_7aXC5gWSp_GgJcv7RpU_FDaboY9UciMlHGaeVVoSGcbMiUPmVPUETe6PuxhYB1PWraxPJxkTHY$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!5oiSwqmtCLR8sv1y_7aXC5gWSp_GgJcv7RpU_FDaboY9UciMlHGaeVVoSGcbMiUPmVPUETe6PuxhYB1PWraxLldj1Qk$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!5oiSwqmtCLR8sv1y_7aXC5gWSp_GgJcv7RpU_FDaboY9UciMlHGaeVVoSGcbMiUPmVPUETe6PuxhYB1PWrax4skTbYk$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Jul 25 19:46:12 2026

FOUS30 KWBC 251945
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
345 PM EDT Sat Jul 25 2026

Day 1
Valid 16Z Sat Jul 25 2026 - 12Z Sun Jul 26 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR THE EASTERN
CAROLINAS AND THE SOUTHWEST...

...Southeast through the Lower Mississippi and Tennessee Valleys...

Deep moisture will continue to pool along and near a stalled
frontal boundary, which leads to precipitable water values reaching
nearly 3 standardized anomalies above climatology for late July
and in excess of the 95th percentile of climatology extending
eastward from the Lower Mississippi and Tennessee Valleys to the
Carolinas. Recent CAMs continue to point to heavy rainfall
potential, with localized 2-4 inch totals with higher instantaneous
rainfall rates, especially in the eastern Carolinas where the
Slight Risk remains. Refer to MPD 846 for more on the threat into
this afternoon. Trimmed off the northern side of the Slight given
less instability to the north of the front in this issuance.
However, did expand the Marginal northward a bit farther west to
cover the southern Appalachians, where localized convection could
be present this evening and tonight over areas with wetter
antecedent conditions and lower FFG.

Farther west, recent guidance remains less enthusiastic compared
to a day ago regarding heavy rainfall in and around Arkansas. With
the 00Z and 12Z CAM/HREF cycles both laying off on heavy rain, felt
confident enough to remove the Slight Risk there. The 12Z HREF
does show some 30-40 percent probabilities of QPF exceeding FFG
near the Mississippi/western Tennessee border that could be a
relatively higher risk, but with too low confidence in impacts to
upgrade to a Slight there.

Scattered thunderstorms across Florida could also cause localized
heavy rain, but currently consider that to be sub-Marginal as EAS
probabilities of exceeding 2 inches is only around 10 percent, and
over the Everglades rather than the more sensitive urban corridor.

...Southwest...

The monsoon will get re-invigorated across the Four Corners today
with an uptick in coverage and intensity of rainfall expected in
the region. Instability could be 1000-2000 J/kg while precipitable
water values are forecast to be above the 90th percentile. An MCV
in the vicinity could become a key player in enhancing the rainfall
which leads to greater/higher rain rates. Concern is heightened
given the possibility that the higher rainfall rates/amounts
overlaps with areas which have recently dealt with heavy rainfall
and where soils will be less capable of handling the influx of rain
water. The Marginal and Slight Risks still look on track and were
adjusted only minimally from the previous issuance.

Tate/Bann

Day 2
Valid 12Z Sun Jul 26 2026 - 12Z Mon Jul 27 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL ACROSS THE FOUR
CORNERS REGION...MIDWEST...AND PORTIONS OF THE SOUTHEAST/FLORIDA...

...Four Corners States onto the Central Plains...

Monsoonal flow from the Desert Southwest to the central Rockies
continues into early next week. Above average precipitable water
values and available instability will again support isolated to
widely scattered thunderstorms capable of producing intense rain
rates capable of producing flash flooding. There may be a general
focus for moisture/instability axis to extend farther north than
Saturday, and there is some signal in the CAMs and global guidance
to focus the greatest coverage of heavy rain into western/central Colorado. Will hold off on any Slight Risk upgrade though due to
uncertainties in the impacts, as well as uncertainties with
instability after an active monsoon Saturday.

...Upper Midwest-Upper Great Lakes-Ohio Valley...

Global, CAM, and AI guidance continue to show convectively-aided
shortwave activity riding down the top side of the upper ridge axis
in northwest flow. A northwest to southeast oriented stationary
front could also provide a convective focus as slightly above
normal PWs but very strong instability come in. However, models
show quite a bit of spread in position of these ridge riders
especially for a short range forecast. The location of convection
will be affected by placement of upper level convergence associated
with a broad arching anticyclonic flow at the jet level. Adjusted
the Marginal Risk to fit with a middle ground model "consensus,"
but it does not cover all the CAM and global model scenarios, so
may need to be adjusted further. Fast movement will be a mitigating
factor for flooding though.

...Southeast into Florida...

Above average moisture will continue to flow into the southeastern
U.S. into a quasi-stationary front with possible waves of low
pressure stretching across Georgia and South Carolina at the base
of an eastern U.S. trough. This front and a surface trough across
Florida should focus the moisture for convection. 90+ percentile
PWs are present along the eastern coast of Florida, where urban
corridors can increase sensitivity to high rainfall rates. A
Marginal Risk covers the threat of isolated flash flooding with
this activity.

Tate/Bann

Day 3
Valid 12Z Mon Jul 27 2026 - 12Z Tue Jul 28 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL MONDAY ACROSS
THE FOUR CORNERS STATES TO CENTRAL PLAINS AND GREAT LAKES/OHIO
VALLEY...

...Four Corners States into the Central Plains...

Elevated amounts of moisture will linger over the Four Corners
region given a persistent monsoon pattern, although guidance still
points to a gradual southward shift in the placement of the upper
high center. This may slightly reduce thunderstorm coverage in
areas like Utah to the Four Corners themselves, but a weak
shortwave looks to move across Colorado and vicinity Monday into
Monday night and enhance convection there and spreading into the
central Plains overnight. Maintained a Marginal Risk area in the Four
Corners states and extending eastward into the central High Plains
to cover the isolated flash flooding threat. Plots of ECMWF PW
anomaly plots continue to prove helpful in highlighting areas of
increased concern.

...Great Lakes and Ohio Valley into the Northeast US...

By Monday a more potent shortwave will move southeastward through
the Upper Great Lakes region rounding the Rockies/High Plains high.
Difluent flow ahead of the shortwave will eventually lead to the consolidation/strengthening of a low pressure system during the
period. This low is expected to help forcing for heavier rainfall
over the Great Lakes/Ohio Valley, with less model spread than the
Sunday convection likely due to greater forcing. A Marginal Risk
remains in place, but convective activity should be relatively
progressive, which is still expected to mitigate any higher risks
of excessive rainfall.

Tate/Bann

Day 4 and Day 5

Valid 12Z Tue Jul 28 2026 - 12Z Thu Jul 30 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE WEST, PLAINS, & EAST...

...Four Corners States into the Central/Northern Plains...
Monsoonal flow, likely to be enhanced by Genevieve moving offshore
Baja California, brings elevated moisture over the Desert
Southwest through the central Rockies and into the central and
northern Plains. The more suppressed ridge will allow multiple mesoscale/convectively aided shortwaves to push over the top/across
the Rockies into the Plains.

...Central Appalachians-Mid Atlantic through New England...
Upper level jet streak riding down the northeast side of a warm
core ridge on Tuesday will lead to amplification of the longwave
trough across the Eastern U.S. by the middle-later part of next
week, leading to a deep layer, eventually coastal, low. Whenever
favorable (typical) warm- season thermodynamics (deep- layer
instability and moisture) are present ahead of a more robust,
cooler-season trough with strong deep- layer shear, chances for
more widespread convection are much higher. Though a Slight Risk
was contemplated from eastern Long Island through southern New
England as far north as Portland ME where a few pieces of guidance
advertise 2-4" on day 5/Wednesday into Wednesday night,
coordination with the local forecast offices maintained the
Marginal Risk from continuity. Sooner or later, a Slight Risk will
probably be needed, especially once the event moves into the high
res (CAM) windows and the QPF signal becomes less variable and more
robust.

Roth

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!_xVwoYCz43Yfq2E-vld1CxvNlTv4OyvoZzu8dFclM7UVIITra-REwQbdhzjhDOlJxdI1HezTs177VDJNMs9A_b7cN_s$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!_xVwoYCz43Yfq2E-vld1CxvNlTv4OyvoZzu8dFclM7UVIITra-REwQbdhzjhDOlJxdI1HezTs177VDJNMs9AA3ji9xg$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!_xVwoYCz43Yfq2E-vld1CxvNlTv4OyvoZzu8dFclM7UVIITra-REwQbdhzjhDOlJxdI1HezTs177VDJNMs9AcCyGx58$

$$

= = =
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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Jul 25 20:58:10 2026

FOUS30 KWBC 252057
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
457 PM EDT Sat Jul 25 2026

Day 1
Valid 16Z Sat Jul 25 2026 - 12Z Sun Jul 26 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR THE EASTERN
CAROLINAS AND THE SOUTHWEST...

...Southeast through the Lower Mississippi and Tennessee Valleys...
Deep moisture will continue to pool along and near a stalled
frontal boundary, which leads to precipitable water values reaching
nearly 3 standardized anomalies above climatology for late July
and in excess of the 95th percentile of climatology extending
eastward from the Lower Mississippi and Tennessee Valleys to the
Carolinas. Recent CAMs continue to point to heavy rainfall
potential, with localized 2-4 inch totals with higher instantaneous
rainfall rates, especially in the eastern Carolinas where the
Slight Risk remains. Refer to MPD 846 for more on the threat into
this afternoon. Trimmed off the northern side of the Slight given
less instability to the north of the front in this issuance.
However, did expand the Marginal northward a bit farther west to
cover the southern Appalachians, where localized convection could
be present this evening and tonight over areas with wetter
antecedent conditions and lower FFG.

Farther west, recent guidance remains less enthusiastic compared
to a day ago regarding heavy rainfall in and around Arkansas. With
the 00Z and 12Z CAM/HREF cycles both laying off on heavy rain, felt
confident enough to remove the Slight Risk there. The 12Z HREF
does show some 30-40 percent probabilities of QPF exceeding FFG
near the Mississippi/western Tennessee border that could be a
relatively higher risk, but with too low confidence in impacts to
upgrade to a Slight there.

Scattered thunderstorms across Florida could also cause localized
heavy rain, but currently consider that to be sub-Marginal as EAS
probabilities of exceeding 2 inches is only around 10 percent, and
over the Everglades rather than the more sensitive urban corridor.

...Southwest...
The monsoon will get re-invigorated across the Four Corners today
with an uptick in coverage and intensity of rainfall expected in
the region. Instability could be 1000-2000 J/kg while precipitable
water values are forecast to be above the 90th percentile. An MCV
in the vicinity could become a key player in enhancing the rainfall
which leads to greater/higher rain rates. Concern is heightened
given the possibility that the higher rainfall rates/amounts
overlaps with areas which have recently dealt with heavy rainfall
and where soils will be less capable of handling the influx of rain
water. The Marginal and Slight Risks still look on track and were
adjusted only minimally from the previous issuance.

Tate/Bann

Day 2
Valid 12Z Sun Jul 26 2026 - 12Z Mon Jul 27 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL ACROSS THE FOUR
CORNERS REGION...MIDWEST...AND PORTIONS OF THE SOUTHEAST/FLORIDA...

...Four Corners States onto the Central Plains...
Monsoonal flow from the Desert Southwest to the central Rockies
continues into early next week. Above average precipitable water
values and available instability will again support isolated to
widely scattered thunderstorms capable of producing intense rain
rates capable of producing flash flooding. There may be a general
focus for moisture/instability axis to extend farther north than
Saturday, and there is some signal in the CAMs and global guidance
to focus the greatest coverage of heavy rain into western/central
Colorado. Will hold off on any Slight Risk upgrade though due to
uncertainties in the impacts, as well as uncertainties with
instability after an active monsoon Saturday.

...Upper Midwest-Upper Great Lakes-Ohio Valley...
Global, CAM, and AI guidance continue to show convectively-aided
shortwave activity riding down the top side of the upper ridge axis
in northwest flow. A northwest to southeast oriented stationary
front could also provide a convective focus as slightly above
normal PWs but very strong instability come in. However, models
show quite a bit of spread in position of these ridge riders
especially for a short range forecast. The location of convection
will be affected by placement of upper level convergence associated
with a broad arching anticyclonic flow at the jet level. Adjusted
the Marginal Risk to fit with a middle ground model "consensus,"
but it does not cover all the CAM and global model scenarios, so
may need to be adjusted further. Fast movement will be a mitigating
factor for flooding though.

...Southeast into Florida...
Above average moisture will continue to flow into the southeastern
U.S. into a quasi-stationary front with possible waves of low
pressure stretching across Georgia and South Carolina at the base
of an eastern U.S. trough. This front and a surface trough across
Florida should focus the moisture for convection. 90+ percentile
PWs are present along the eastern coast of Florida, where urban
corridors can increase sensitivity to high rainfall rates. A
Marginal Risk covers the threat of isolated flash flooding with
this activity.

Tate/Bann

Day 3
Valid 12Z Mon Jul 27 2026 - 12Z Tue Jul 28 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL MONDAY ACROSS
THE FOUR CORNERS STATES TO CENTRAL PLAINS AND GREAT LAKES/OHIO
VALLEY...

...Four Corners States into the Central Plains...
Elevated amounts of moisture will linger over the Four Corners
region given a persistent monsoon pattern, although guidance still
points to a gradual southward shift in the placement of the upper
high center. This may slightly reduce thunderstorm coverage in
areas like Utah to the Four Corners themselves, but a weak
shortwave looks to move across Colorado and vicinity Monday into
Monday night and enhance convection there and spreading into the
central Plains overnight. Maintained a Marginal Risk area in the
Four Corners states and extending eastward into the central High
Plains to cover the isolated flash flooding threat. Plots of ECMWF
PW anomaly plots continue to prove helpful in highlighting areas of
increased concern.

...Great Lakes and Ohio Valley into the Northeast US...
By Monday a more potent shortwave will move southeastward through
the Upper Great Lakes region rounding the Rockies/High Plains high.
Difluent flow ahead of the shortwave will eventually lead to the consolidation/strengthening of a low pressure system during the
period. This low is expected to help forcing for heavier rainfall
over the Great Lakes/Ohio Valley, with less model spread than the
Sunday convection likely due to greater forcing. A Marginal Risk
remains in place, but convective activity should be relatively
progressive, which is still expected to mitigate any higher risks
of excessive rainfall.

Tate/Bann

Day 4 and Day 5

Valid 12Z Tue Jul 28 2026 - 12Z Thu Jul 30 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE WEST, PLAINS, & EAST...

...Four Corners States into the Central/Northern Plains...
Monsoonal flow, likely to be enhanced by Genevieve moving offshore
Baja California, brings elevated moisture over the Desert
Southwest through the central Rockies and into the central and
northern Plains. The more suppressed ridge will allow multiple mesoscale/convectively aided shortwaves to push over the top/across
the Rockies into the Plains.

...Central Appalachians-Mid Atlantic through New England...
Upper level jet streak riding down the northeast side of a warm
core ridge on Tuesday will lead to amplification of the longwave
trough across the Eastern U.S. by the middle-later part of next
week, leading to a deep layer, eventually coastal, low. Whenever
favorable (typical) warm- season thermodynamics (deep- layer
instability and moisture) are present ahead of a more robust,
cooler-season trough with strong deep- layer shear, chances for
more widespread convection are much higher. Though a Slight Risk
was contemplated from eastern Long Island through southern New
England as far north as Portland ME where a few pieces of guidance
advertise 2-4" on day 5/Wednesday into Wednesday night,
coordination with the local forecast offices maintained the
Marginal Risk from continuity. Sooner or later, a Slight Risk will
probably be needed, especially once the event moves into the high
res (CAM) windows and the QPF signal becomes less variable and more
robust.

...Southeast...
Heavy rainfall is expected along the New England cyclone's trailing
front near the FL/GA border. Moisture should be ample and there
could be enough effective bulk shear for convective organization.
Since to some signal seen in the model guidance in this region,
added a Marginal Risk area.

Roth

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!_JcVzXRZ2G3STarpAzr3boBsxwMIs0f9fLSEfah5_sc6rfNHrI0j6APh3l3cf1cJLKrPM_DUqv94B_EvT7SwUSVcCHw$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!_JcVzXRZ2G3STarpAzr3boBsxwMIs0f9fLSEfah5_sc6rfNHrI0j6APh3l3cf1cJLKrPM_DUqv94B_EvT7SwehC7yTs$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!_JcVzXRZ2G3STarpAzr3boBsxwMIs0f9fLSEfah5_sc6rfNHrI0j6APh3l3cf1cJLKrPM_DUqv94B_EvT7Sw2TX_oW0$

$$

= = =
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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sat Jul 25 23:56:18 2026

FOUS30 KWBC 252356
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
756 PM EDT Sat Jul 25 2026

Day 1
Valid 01Z Sun Jul 26 2026 - 12Z Sun Jul 26 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR THE SAVANNAH
RIVER VALLEY AND SOUTHWEST...

...Southeast through the Lower Mississippi and Tennessee Valleys...
Deep moisture will continue to pool along and near a stalled
frontal boundary, has led to extensive moisture from the southern
Appalachians across SC. A couple rounds of heavy rainfall are
expected -- one early across SC and one later on in and near the
Southern Appalachians over lower flash flood guidance/more rugged
terrain -- led to a rearrangement of the Slight Risk area across
the region. Hourly amounts to 2.5" can't be ruled out.

Scattered thunderstorms across Florida early, and then near the
Southwest coast and Keys late, could also cause localized heavy
rain. Reconfigured the Marginal Risk area somewhat to account for
the 18z HREF/12z REFS probabilities in this area.

...Southwest...
Monsoonal moisture/instability has led to convection across the
region this afternoon. An MCV in the vicinity still appears to be
a key player in enhancing the rainfall which leads to
greater/higher rain rates. Based on radar reflectivity/HREF and
REFS probabilities of 0.5"+ through 12z, some reductions were made
to the Marginal and Slight Risk areas across CO and NM while the
Marginal Risk area was expanded into the Lower Deserts/towards the
Lower CO River where an outflow boundary and some preceding
convection could lead to cell mergers early this evening.

...South Dakota...
Convection across the state hasn't shown much alignment as of yet,
but there is some risk for repeat convection in the near term based
on recent radar reflectivity data. The region has been dry, so
left out any risk areas for the time being. Isolated flash flooding
can't be ruled out completely if cells manage to train/align.

Roth

Day 2
Valid 12Z Sun Jul 26 2026 - 12Z Mon Jul 27 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL ACROSS THE FOUR
CORNERS REGION...MIDWEST...AND PORTIONS OF THE SOUTHEAST/FLORIDA...

...Four Corners States onto the Central Plains...
Monsoonal flow from the Desert Southwest to the central Rockies
continues into early next week. Above average precipitable water
values and available instability will again support isolated to
widely scattered thunderstorms capable of producing intense rain
rates capable of producing flash flooding. There may be a general
focus for moisture/instability axis to extend farther north than
Saturday, and there is some signal in the CAMs and global guidance
to focus the greatest coverage of heavy rain into western/central
Colorado. Will hold off on any Slight Risk upgrade though due to
uncertainties in the impacts, as well as uncertainties with
instability after an active monsoon Saturday.

...Upper Midwest-Upper Great Lakes-Ohio Valley...
Global, CAM, and AI guidance continue to show convectively-aided
shortwave activity riding down the top side of the upper ridge axis
in northwest flow. A northwest to southeast oriented stationary
front could also provide a convective focus as slightly above
normal PWs but very strong instability come in. However, models
show quite a bit of spread in position of these ridge riders
especially for a short range forecast. The location of convection
will be affected by placement of upper level convergence associated
with a broad arching anticyclonic flow at the jet level. Adjusted
the Marginal Risk to fit with a middle ground model "consensus,"
but it does not cover all the CAM and global model scenarios, so
may need to be adjusted further. Fast movement will be a mitigating
factor for flooding though.

...Southeast into Florida...
Above average moisture will continue to flow into the southeastern
U.S. into a quasi-stationary front with possible waves of low
pressure stretching across Georgia and South Carolina at the base
of an eastern U.S. trough. This front and a surface trough across
Florida should focus the moisture for convection. 90+ percentile
PWs are present along the eastern coast of Florida, where urban
corridors can increase sensitivity to high rainfall rates. A
Marginal Risk covers the threat of isolated flash flooding with
this activity.

Tate/Bann

Day 3
Valid 12Z Mon Jul 27 2026 - 12Z Tue Jul 28 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL MONDAY ACROSS
THE FOUR CORNERS STATES TO CENTRAL PLAINS AND GREAT LAKES/OHIO
VALLEY...

...Four Corners States into the Central Plains...
Elevated amounts of moisture will linger over the Four Corners
region given a persistent monsoon pattern, although guidance still
points to a gradual southward shift in the placement of the upper
high center. This may slightly reduce thunderstorm coverage in
areas like Utah to the Four Corners themselves, but a weak
shortwave looks to move across Colorado and vicinity Monday into
Monday night and enhance convection there and spreading into the
central Plains overnight. Maintained a Marginal Risk area in the
Four Corners states and extending eastward into the central High
Plains to cover the isolated flash flooding threat. Plots of ECMWF
PW anomaly plots continue to prove helpful in highlighting areas of
increased concern.

...Great Lakes and Ohio Valley into the Northeast US...
By Monday a more potent shortwave will move southeastward through
the Upper Great Lakes region rounding the Rockies/High Plains high.
Difluent flow ahead of the shortwave will eventually lead to the consolidation/strengthening of a low pressure system during the
period. This low is expected to help forcing for heavier rainfall
over the Great Lakes/Ohio Valley, with less model spread than the
Sunday convection likely due to greater forcing. A Marginal Risk
remains in place, but convective activity should be relatively
progressive, which is still expected to mitigate any higher risks
of excessive rainfall.

Tate/Bann

Day 4 and Day 5

Valid 12Z Tue Jul 28 2026 - 12Z Thu Jul 30 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE WEST, PLAINS, & EAST...

...Four Corners States into the Central/Northern Plains...
Monsoonal flow, likely to be enhanced by Genevieve moving offshore
Baja California, brings elevated moisture over the Desert
Southwest through the central Rockies and into the central and
northern Plains. The more suppressed ridge will allow multiple mesoscale/convectively aided shortwaves to push over the top/across
the Rockies into the Plains.

...Central Appalachians-Mid Atlantic through New England...
Upper level jet streak riding down the northeast side of a warm
core ridge on Tuesday will lead to amplification of the longwave
trough across the Eastern U.S. by the middle-later part of next
week, leading to a deep layer, eventually coastal, low. Whenever
favorable (typical) warm- season thermodynamics (deep- layer
instability and moisture) are present ahead of a more robust,
cooler-season trough with strong deep- layer shear, chances for
more widespread convection are much higher. Though a Slight Risk
was contemplated from eastern Long Island through southern New
England as far north as Portland ME where a few pieces of guidance
advertise 2-4" on day 5/Wednesday into Wednesday night,
coordination with the local forecast offices maintained the
Marginal Risk from continuity. Sooner or later, a Slight Risk will
probably be needed, especially once the event moves into the high
res (CAM) windows and the QPF signal becomes less variable and more
robust.

...Southeast...
Heavy rainfall is expected along the New England cyclone's trailing
front near the FL/GA border. Moisture should be ample and there
could be enough effective bulk shear for convective organization.
Since to some signal seen in the model guidance in this region,
added a Marginal Risk area.

Roth

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!5zFeMIXyGfoR54OYatFD4P4e_6jeWEMddKIQnSerKE1AUBmTUo8LAKTmlx3u-o-oNFLfOmNnjbyKSuXZHUtlaUaTPHk$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!5zFeMIXyGfoR54OYatFD4P4e_6jeWEMddKIQnSerKE1AUBmTUo8LAKTmlx3u-o-oNFLfOmNnjbyKSuXZHUtlbkmdcsc$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!5zFeMIXyGfoR54OYatFD4P4e_6jeWEMddKIQnSerKE1AUBmTUo8LAKTmlx3u-o-oNFLfOmNnjbyKSuXZHUtlC1ViB7Y$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sun Jul 26 08:28:54 2026

FOUS30 KWBC 260828
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
428 AM EDT Sun Jul 26 2026

Day 1
Valid 12Z Sun Jul 26 2026 - 12Z Mon Jul 27 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER COASTAL
PORTIONS OF THE SOUTHEAST US...

...Southeast into Florida...
Above average moisture will remain over the southeastern U.S. with
low level flow near a lingering quasi-stationary front with
continuing to feed moisture into the area while poorly defined
waves of low pressure stretching across the base of an eastern
U.S. trough will focus/enhance the convection near coastal South Carolina/Georgia. Given how slow the front has been to depart the
area...opted to extend yesterday's Slight Risk area into the new
Day 1 period.

A Marginal Risk area extends southward along much of the east
coast of Florida. There is abundant deep-layer moisture in place as
shown by the 90+ percentile values of precipitable water which
suggests cells should be efficient rainfall producers with
localized rainfall rates in excess of 3 inches possible and
rainfall totals generally 2 to 4 inches. Urban corridors can
increase sensitivity to high rainfall rates but overall a Marginal
Risk covers the threat of isolated flash flooding.

...Four Corners States onto the Central Plains...
Monsoonal flow from the Desert Southwest to the central Rockies
continues into early next week. Above average precipitable water
values and available instability will again support isolated to
widely scattered thunderstorms capable of producing intense rain
rates capable of producing flash flooding and a multiple weak
shortwaves to help focus the daily convection. Some signals remain in
the convective allowing models to focus the greatest coverage of
heavy rain into western/central Colorado. Held off on any Slight
Risk upgrade again given the uncertainties in the impacts.

...Upper Midwest-Upper Great Lakes-Ohio Valley...
Global, CAM, and AI guidance continue to show convectively-aided
shortwave activity riding down the top side of the upper ridge axis
in northwest flow. A northwest to southeast oriented stationary
front could also provide a convective focus as slightly above
normal PWs but very strong instability come in. Models continue to
show considerable spread in terms of where these ridge riders form
and track. The location of convection will be affected by
placement of upper level convergence associated with a broad
arching anticyclonic flow at the jet level. The potential for flash
flooding will be mitigated by the progressive nature of individual
storms.

Bann/Tate

Day 2
Valid 12Z Mon Jul 27 2026 - 12Z Tue Jul 28 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL MONDAY ACROSS
THE FOUR CORNERS STATES TO CENTRAL PLAINS AND GREAT LAKES/OHIO
VALLEY...

...Four Corners States into the Central Plains...
The outlook changed little this cycle given the amount of run to
run continuity shown by the guidance. Elevated amounts of moisture
will linger over the Four Corners region given a persistent
monsoon pattern, although guidance still points to a gradual
southward shift in the placement of the upper high center. This
should result in a subtle shift in the location of the heaviest
rainfall potential but not enough to make more than nudges to the
Marginal Risk area in the Four Corners states. Circulation around
the northern periphery of the high will transport the moisture and
chance of showers and thunderstorms eastward into the central High
Plains. The ECMWF precipitable water plots have been pointing to
this for several runs so the possibility was already well covered.

...Great Lakes and Ohio Valley into the Northeast US...
By Monday a more potent shortwave will move southeastward through
the Upper Great Lakes region rounding the Rockies/High Plains high. Increasingly difluent flow ahead of the shortwave will eventually
lead to the consolidation/strengthening of a low pressure system
during the period which in turn help increasing the forcing for
heavier rainfall over the Great Lakes/Ohio Valley. A Marginal Risk
remained in place.

Bann/Tate

Day 3
Valid 12Z Tue Jul 28 2026 - 12Z Wed Jul 29 2026

...Central Appalachians-Mid Atlantic through New England...
Introduced a Slight Risk area over portions of New York southward
into a portion of the Mid-Atlantic on Tuesday. Precipitable water
values over the region begin close to 2 inches as an area of low
pressure begins to take shape in response to the amplification of
an upper trough. Divergence aloft increases notably as the winds at
jet-stream level become increasingly difluent. Whenever favorable
(typical) warm-season thermodynamics are present ahead of a more
robust, cooler-season trough with strong deep-layer shear, chances
for more widespread convection increase. Although a Slight Risk
was introduced..a realignment or expansion is possible as the
evolution becomes more clear. The 26/00Z guidance still has a few
pieces of guidance that advertise 2-4" on Wednesday into Wednesday
night.

...Four Corners States into the Central/Northern Plains...
Monsoonal flow of moisture, likely to be enhanced by Genevieve
moving offshore Baja California,looks to elevate moisture over the
Desert Southwest through the central Rockies and into the central
and northern Plains with time. The more suppressed ridge will
allow multiple mesoscale/convectively aided shortwaves to push over
the top/across the Rockies into the Plains.

...Southeast...
A continued threat for heavy rainfall lingers along the New
England cyclone's trailing front near the FL/GA border. Moisture
should be ample and there could be enough effective bulk shear for
convective organization. Since to some signal seen in the model
guidance in this region, maintained a Marginal Risk area.

Bann

Day 4 and Day 5

Valid 12Z Wed Jul 29 2026 - 12Z Fri Jul 31 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
NORTHEAST WEDNESDAY...

...Northeast...
Quite a dynamic coastal system taking shape Wed-Thu along the New
England Coast per the global models and ensembles. Strong upper
level jet energy upstream diving toward the trough base will
amplify the upper trough -- to the tune of 2+ standard deviations
at 500 mb per the latest GEFS -- which in-turn will enhance the
downstream QG forcing (upper diffluence/divergence and deep-layer
ascent). Strengthening southerly low-level flow will draw in
moisture-rich air off the Atlantic Gulf stream, with a swath of
1.8-2.0+ inch PWs within the deepening TROWAL pivoting around the
slow-moving comma head. Given the persistence of favorable "cool
season" dynamics with "warm season" thermodynamics (high deep-
layer TPW/theta-e values), feel confident in hoisting a Day 4
Slight Risk area across parts of the Northeast to include the Tri-
State area and southern New England.

Even without the benefit of high-res CAM runs, the operational
global runs (and several ensembles to boot) show areas of 3-4+
inches within 24hrs across the Slight Risk areas, while their
perspective ensemble probabilities of these QPF thresholds have
come up considerably with the 00Z 07/26 runs. Instability will
likely be capped at 1000 J/Kg if not lower ("tall/skinny" CAPE
profile); however considering the persistent deep-layer forcing and moisture/TPW anomaly, the amount of CAPE or lack thereof should
not inhibit a Slight Risk for excessive rainfall within this area,
which is supported by the 00Z 7/26 CSU First-Guess ERO fields (UFVS
verified version). 12Z 7/26 ECMWF EFI noted a broadening area over
0.7 with a shift-of-tails to 1. Will be keeping an eye on these
trends over the next few days prior to this event, as an upgrade to
Moderate somewhere in/near the Sight Risk area will be possible.

...Four Corners States into the Central/Northern Plains...
Monsoonal flow, likely to be enhanced by Genevieve moving offshore
Baja California, brings elevated moisture over the Desert
Southwest through the central Rockies and into the central and
northern Plains. The more suppressed ridge will allow multiple mesoscale/convectively aided shortwaves to push over the top/across
the Rockies into the Plains.

...Lower Missouri Valley into the Upper Mississippi Valley...
On Day 5 (Thursday-Thursday night), convectively-aided shortwave
energy progressing east from the central-northern Plains will
amplify a bit (dig a bit farther south) upon reaching the Lower
MO-Mid MS Valleys) during this time as the ~600DM 500mb high
becomes centered farther west toward the Four Corners. Still some
discrepancy amongst the global guidance (GFS most vigorous with the
deep-layer forcing and low-level moisture transport), however all
the models are trending towards a wetter solution with the
likelihood of an MCS/upscale convective growth within an area of
expanding PWs of 2-2.25+ inches. Could certainly see a bump up to
Slight Risk at some point, but for now given the latitudinal spread
in the guidance, have opted to go with a Marginal Risk in the D5
ERO for now.

...Central Gulf Coast Region into parts of the Southeast...
Heavy rainfall is expected along the New England cyclone's
trailing front near the FL/GA border. Moisture should be ample and
there could be enough effective bulk shear for convective
organization. Since to some signal seen in the model guidance in
this region, added a Marginal Risk area.

Hurley/Roth

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!9WScZp7ED0HcmyQLUu2b1hjhw4Q8vaehuuUIwukKvE6S4QV4BAa-DFtlykR4dJjhHL9XDy2pMl9c1f844ZL74ZDBHX0$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!9WScZp7ED0HcmyQLUu2b1hjhw4Q8vaehuuUIwukKvE6S4QV4BAa-DFtlykR4dJjhHL9XDy2pMl9c1f844ZL7W-Cqk_c$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!9WScZp7ED0HcmyQLUu2b1hjhw4Q8vaehuuUIwukKvE6S4QV4BAa-DFtlykR4dJjhHL9XDy2pMl9c1f844ZL7Tex5FkA$

$$

= = =
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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sun Jul 26 16:01:16 2026

FOUS30 KWBC 261600
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1200 PM EDT Sun Jul 26 2026

Day 1
Valid 16Z Sun Jul 26 2026 - 12Z Mon Jul 27 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER A PORTION OF
COASTAL SOUTH CAROLINA AND GEORGIA...

...South Carolina through the Atlantic coast of Florida...

Above average moisture remains over South Carolina into GA with
low level flow near a lingering quasi- stationary front
continuing to feed moisture into the area while poorly defined
waves of low pressure stretching across the base of an eastern U.S.
trough should focus/enhance the convection near coastal South
Carolina/Georgia. Maintained/trimmed Slight Risk from the north.

A Marginal Risk area extends southward along much of the east
coast of Florida. There is abundant deep-layer moisture in place as
shown by the 90+ percentile values of precipitable water which
suggests cells should be efficient rainfall producers with
localized rainfall rates in excess of 3 inches possible and
rainfall totals generally 2 to 4 inches. Urban corridors can
increase sensitivity to high rainfall rates but overall a Marginal
Risk covers the threat of isolated flash flooding.

...Four Corners States...

Monsoonal flow through the Desert Southwest to the central Rockies
west of the upper high center over eastern CO. Above average
precipitable water values and available instability will again
support isolated to widely scattered thunderstorms capable of
producing intense rain rates capable of producing flash flooding.
Northern AZ and western CO are still targets for greatest coverage
in 12Z CAMs.

...Upper Midwest-Upper Great Lakes-Ohio Valley...

Progressive, organized activity late this afternoon through the
overnight from the Upper Midwest through the Tennessee Valley in
NW to NNW flow downstream of the mid-level ridge axis along the
western Dakota border. There is a risk for repeating MCS activity
as well as repeating cells where boundaries become parallel to mean
layer flow. Therefore, expanding the Marginal Risk from Duluth to
Atlanta comprising all of Wisconsin and Illinois. Some guidance
like the 12Z ARW2 shifts farther west over western IA, so that will
need to be monitored.

...North-central Virginia into central North Carolina...

Strong agreement among 12Z HREF/REFS guidance on lee-side trough
activity developing this evening over north-central VA under a
reinforcing impulse on the main trough axis over the Eastern
Seaboard. This activity shifts/propagates south ahead of the mid-
level impulse reaching central NC late tonight. Near to a bit above
normal moisture accompanies this activity with PW around 1.75",
which should limit the capacity of this activity to isolated flash
flooding (a Marginal Risk).

Jackson

Day 2
Valid 12Z Mon Jul 27 2026 - 12Z Tue Jul 28 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL MONDAY ACROSS
THE FOUR CORNERS STATES TO CENTRAL PLAINS AND GREAT LAKES/OHIO
VALLEY...

...Four Corners States into the Central Plains...
The outlook changed little this cycle given the amount of run to
run continuity shown by the guidance. Elevated amounts of moisture
will linger over the Four Corners region given a persistent
monsoon pattern, although guidance still points to a gradual
southward shift in the placement of the upper high center. This
should result in a subtle shift in the location of the heaviest
rainfall potential but not enough to make more than nudges to the
Marginal Risk area in the Four Corners states. Circulation around
the northern periphery of the high will transport the moisture and
chance of showers and thunderstorms eastward into the central High
Plains. The ECMWF precipitable water plots have been pointing to
this for several runs so the possibility was already well covered.

...Great Lakes and Ohio Valley into the Northeast US...
By Monday a more potent shortwave will move southeastward through
the Upper Great Lakes region rounding the Rockies/High Plains high. Increasingly difluent flow ahead of the shortwave will eventually
lead to the consolidation/strengthening of a low pressure system
during the period which in turn help increasing the forcing for
heavier rainfall over the Great Lakes/Ohio Valley. A Marginal Risk
remained in place.

Bann/Tate

Day 3
Valid 12Z Tue Jul 28 2026 - 12Z Wed Jul 29 2026

...Central Appalachians-Mid Atlantic through New England...
Introduced a Slight Risk area over portions of New York southward
into a portion of the Mid-Atlantic on Tuesday. Precipitable water
values over the region begin close to 2 inches as an area of low
pressure begins to take shape in response to the amplification of
an upper trough. Divergence aloft increases notably as the winds at
jet-stream level become increasingly difluent. Whenever favorable
(typical) warm-season thermodynamics are present ahead of a more
robust, cooler-season trough with strong deep-layer shear, chances
for more widespread convection increase. Although a Slight Risk
was introduced..a realignment or expansion is possible as the
evolution becomes more clear. The 26/00Z guidance still has a few
pieces of guidance that advertise 2-4" on Wednesday into Wednesday
night.

...Four Corners States into the Central/Northern Plains...
Monsoonal flow of moisture, likely to be enhanced by Genevieve
moving offshore Baja California,looks to elevate moisture over the
Desert Southwest through the central Rockies and into the central
and northern Plains with time. The more suppressed ridge will
allow multiple mesoscale/convectively aided shortwaves to push over
the top/across the Rockies into the Plains.

...Southeast...
A continued threat for heavy rainfall lingers along the New
England cyclone's trailing front near the FL/GA border. Moisture
should be ample and there could be enough effective bulk shear for
convective organization. Since to some signal seen in the model
guidance in this region, maintained a Marginal Risk area.

Bann

Day 4 and Day 5

Valid 12Z Wed Jul 29 2026 - 12Z Fri Jul 31 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
NORTHEAST WEDNESDAY...

...Northeast...
Quite a dynamic coastal system taking shape Wed-Thu along the New
England Coast per the global models and ensembles. Strong upper
level jet energy upstream diving toward the trough base will
amplify the upper trough -- to the tune of 2+ standard deviations
at 500 mb per the latest GEFS -- which in-turn will enhance the
downstream QG forcing (upper diffluence/divergence and deep-layer
ascent). Strengthening southerly low-level flow will draw in
moisture-rich air off the Atlantic Gulf stream, with a swath of
1.8-2.0+ inch PWs within the deepening TROWAL pivoting around the
slow-moving comma head. Given the persistence of favorable "cool
season" dynamics with "warm season" thermodynamics (high deep-
layer TPW/theta-e values), feel confident in hoisting a Day 4
Slight Risk area across parts of the Northeast to include the Tri-
State area and southern New England.

Even without the benefit of high-res CAM runs, the operational
global runs (and several ensembles to boot) show areas of 3-4+
inches within 24hrs across the Slight Risk areas, while their
perspective ensemble probabilities of these QPF thresholds have
come up considerably with the 00Z 07/26 runs. Instability will
likely be capped at 1000 J/Kg if not lower ("tall/skinny" CAPE
profile); however considering the persistent deep-layer forcing and moisture/TPW anomaly, the amount of CAPE or lack thereof should
not inhibit a Slight Risk for excessive rainfall within this area,
which is supported by the 00Z 7/26 CSU First-Guess ERO fields (UFVS
verified version). 12Z 7/26 ECMWF EFI noted a broadening area over
0.7 with a shift-of-tails to 1. Will be keeping an eye on these
trends over the next few days prior to this event, as an upgrade to
Moderate somewhere in/near the Sight Risk area will be possible.

...Four Corners States into the Central/Northern Plains...
Monsoonal flow, likely to be enhanced by Genevieve moving offshore
Baja California, brings elevated moisture over the Desert
Southwest through the central Rockies and into the central and
northern Plains. The more suppressed ridge will allow multiple mesoscale/convectively aided shortwaves to push over the top/across
the Rockies into the Plains.

...Lower Missouri Valley into the Upper Mississippi Valley...
On Day 5 (Thursday-Thursday night), convectively-aided shortwave
energy progressing east from the central-northern Plains will
amplify a bit (dig a bit farther south) upon reaching the Lower
MO-Mid MS Valleys) during this time as the ~600DM 500mb high
becomes centered farther west toward the Four Corners. Still some
discrepancy amongst the global guidance (GFS most vigorous with the
deep-layer forcing and low-level moisture transport), however all
the models are trending towards a wetter solution with the
likelihood of an MCS/upscale convective growth within an area of
expanding PWs of 2-2.25+ inches. Could certainly see a bump up to
Slight Risk at some point, but for now given the latitudinal spread
in the guidance, have opted to go with a Marginal Risk in the D5
ERO for now.

...Central Gulf Coast Region into parts of the Southeast...
Heavy rainfall is expected along the New England cyclone's
trailing front near the FL/GA border. Moisture should be ample and
there could be enough effective bulk shear for convective
organization. Since to some signal seen in the model guidance in
this region, added a Marginal Risk area.

Hurley/Roth

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!6WWTO9QjDtXAXfulKVl8hKSzjZPwiqxKE0wqOqyXXiFS8VELqtqfgT8hwdqX6SWCiN0CL7Oq9pkD7DBJnoqa7qsM3bQ$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!6WWTO9QjDtXAXfulKVl8hKSzjZPwiqxKE0wqOqyXXiFS8VELqtqfgT8hwdqX6SWCiN0CL7Oq9pkD7DBJnoqaoFaWDvI$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!6WWTO9QjDtXAXfulKVl8hKSzjZPwiqxKE0wqOqyXXiFS8VELqtqfgT8hwdqX6SWCiN0CL7Oq9pkD7DBJnoqajM4sK9I$

$$

= = =
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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Sun Jul 26 19:57:34 2026

FOUS30 KWBC 261957
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
357 PM EDT Sun Jul 26 2026

Day 1
Valid 16Z Sun Jul 26 2026 - 12Z Mon Jul 27 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER A PORTION OF
COASTAL SOUTH CAROLINA AND GEORGIA...

...South Carolina through the Atlantic coast of Florida...

Above average moisture remains over South Carolina into GA with
low level flow near a lingering quasi- stationary front
continuing to feed moisture into the area while poorly defined
waves of low pressure stretching across the base of an eastern U.S.
trough should focus/enhance the convection near coastal South
Carolina/Georgia. Maintained/trimmed Slight Risk from the north.

A Marginal Risk area extends southward along much of the east
coast of Florida. There is abundant deep-layer moisture in place as
shown by the 90+ percentile values of precipitable water which
suggests cells should be efficient rainfall producers with
localized rainfall rates in excess of 3 inches possible and
rainfall totals generally 2 to 4 inches. Urban corridors can
increase sensitivity to high rainfall rates but overall a Marginal
Risk covers the threat of isolated flash flooding.

...Four Corners States...

Monsoonal flow through the Desert Southwest to the central Rockies
west of the upper high center over eastern CO. Above average
precipitable water values and available instability will again
support isolated to widely scattered thunderstorms capable of
producing intense rain rates capable of producing flash flooding.
Northern AZ and western CO are still targets for greatest coverage
in 12Z CAMs.

...Upper Midwest-Upper Great Lakes-Ohio Valley...

Progressive, organized activity late this afternoon through the
overnight from the Upper Midwest through the Tennessee Valley in
NW to NNW flow downstream of the mid-level ridge axis along the
western Dakota border. There is a risk for repeating MCS activity
as well as repeating cells where boundaries become parallel to mean
layer flow. Therefore, expanding the Marginal Risk from Duluth to
Atlanta comprising all of Wisconsin and Illinois. Some guidance
like the 12Z ARW2 shifts farther west over western IA, so that will
need to be monitored.

...North-central Virginia into central North Carolina...

Strong agreement among 12Z HREF/REFS guidance on lee-side trough
activity developing this evening over north-central VA under a
reinforcing impulse on the main trough axis over the Eastern
Seaboard. This activity shifts/propagates south ahead of the mid-
level impulse reaching central NC late tonight. Near to a bit above
normal moisture accompanies this activity with PW around 1.75",
which should limit the capacity of this activity to isolated flash
flooding (a Marginal Risk).

Jackson

Day 2
Valid 12Z Mon Jul 27 2026 - 12Z Tue Jul 28 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL ACROSS THE FOUR
CORNERS STATES ONTO THE CENTRAL PLAINS AND GREAT LAKES/OHIO VALLEY
INTO THE NORTHEAST...

...Four Corners States onto the Central Plains...

Center of upper high shifts south from CO to NM through tonight
which will direct more ridge topping diurnally-driven activity
from the central Rockies onto the central Plains on Monday
compared to today. Meanwhile continued monsoonal activity is
expected across the Four Corners states again. Favored focus areas
for QPF are again along the Mogollon Rim in AZ and in CO, though
this time it's east from the Continental Divide instead of west
like today. Only a minor expansion to the Marginal Risk is noted
with the HREF favoring central Plains activity into southwestern
South Dakota.

...Great Lakes and Ohio Valley into the Northeast US...

A shortwave trough shifts southeast over northern Minnesota Monday
morning and through the Upper Great Lakes Monday afternoon/evening.
This is in northwest flow downstream of the upper level ridge axis
stalled over the western Dakota border. Increasingly difluent flow
ahead of the shortwave will lead to the consolidation/
strengthening of a low pressure system Monday night which increases
forcing for heavier rainfall over the Great Lakes/Ohio Valley. The
Marginal Risk was expanded west along the WI/UP of MI border for
morning activity, down through eastern IL for downstream effects
from tonight, and farther downstream into New Jersey for Monday
night activity beginning before it becomes more significant on
Tuesday.

...Tampa Bay...

Troughing currently on the east side of the FL Peninsula shifts to
the Gulf side tomorrow. Excellent agreement among 12Z HREF/REFS
guidance for repeating heavy thunderstorms across greater Tampa Bay
Monday morning into the afternoon. Consensus average QPF is 2-4"
with potential for 6" from both the HREF and RRFS. A Marginal Risk
for flash flooding is warranted in this scenario, especially for
urbanized drainage concerns.

Jackson

Day 3
Valid 12Z Tue Jul 28 2026 - 12Z Wed Jul 29 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR MUCH OF THE
NORTHERN MID-ATLANTIC INTO SOUTHERN NEW ENGLAND...

...Southern Appalachians into New England including northern Mid-
Atlantic...

Shortwave trough develops into a low pressure system over the
eastern Great Lakes Monday night that then stalls over interior
NY/PA Tuesday. There is greater certainly on the interior position
of this low which then maintains the warm sector over the northern
Mid-Atlantic coast into southern New England. 2 inch PW is
highlighted through this warm sector which should also have
sufficient instability for higher rainfall rates along with upper
divergence to promote growth and repeating activity. A Slight Risk
remains over the northern Mid-Atlantic into southern New England
with additional focus now for northern NJ, southern NY (inland of
NYC as of now) into western CT as a higher end slight (aka
"enhanced"). Areal average rainfall of 2-4" with locally higher
amounts is currently forecast for this "enhanced" area.

Elsewhere, warm sector moisture and instability is present down the Mid-Atlantic through North Carolina with potential for south moving
activity to repeat from reinforcing shortwaves rounding the new low
ot the north. Targeted Slight Risks may be warranted in the
southern Mid-Atlantic eventually. Otherwise, the 12Z QPF consensus
favored the southern Appalachians more than before, so they were
added to the Marginal Risk.

...Four Corners States across the Central Plains...

Further suppression of the upper high center south through New
Mexico opens further downstream activity from the Four Corners
states across the central Plains. The Marginal Risk was expanded
east to the KC metro. As of now the RRFS and EC-AIFS highlight the
High Plains of both northeast and southeast CO with more typical
Monsoonal activity over terrain in the Four Corners states.

Jackson

Day 4 and Day 5

Valid 12Z Wed Jul 29 2026 - 12Z Fri Jul 31 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
NORTHEAST WEDNESDAY...

...Northeast...
A dynamic coastal system takes shape Tue-Thu along/near the New
England Coast per model guidance. Strong upper level jet energy
upstream diving toward the trough base will amplify the upper
trough -- to the tune of 2+ standard deviations below late July
means at 500 mb-- which enhances the downstream QG forcing (upper diffluence/divergence and deep-layer ascent). Strengthening
east to south low-level flow will draw in moisture-rich air off
the Atlantic Gulf stream, with a swath of ~1.75" PWs within the
deepening TROWAL pivoting around the slow- moving comma head. Given
the persistence of favorable cool season dynamics with warm season thermodynamics (high deep- layer TPW/theta-e values), have
maintained the Day 4 Slight Risk area across parts of the
Northeast, which fits the most recent global guidance rather well.
Coordination with GYX/Gray ME and BTV/Burlington VT forecast
offices led to some restriction on its north and northeast side,
based on the 3-6 hourly FFGs.

Operational guidance shows 2-4" across the Slight Risk area on day
4/Wednesday into Wednesday night. Soundings will be moist, and
frontogenesis of the comma head could on its own lead to efficient
heavy rainfall; not much MU/ML CAPE will be necessary to lead
to flash flooding concerns. There has been a decided broadening
trend in the heavy rain signal since this time yesterday, and
depending on the degree of heavy rainfall that occurs on
Tuesday/Tuesday night, an upgrade to a Moderate somewhere in/near
the Sight Risk area can't be ruled out. Added a Marginal Risk for Thursday/Thursday night due to some signal for continued heavy
rainfall on day 5.

...Four Corners States into the Central/Northern Plains...
Monsoonal flow, likely to be enhanced by Genevieve moving offshore
Baja California, brings elevated moisture over the Desert
Southwest through the central Rockies and into the central and
northern Plains. The more suppressed ridge will allow multiple mesoscale/convectively aided shortwaves to push over the top/across
the Rockies into the Plains. The Marginal Risk area here only
needed some cosmetic changes to better fit the most recent QPF
guidance.

...Lower Missouri Valley into the Upper Mississippi Valley...
On Day 5 (Thursday-Thursday night), convectively-aided shortwave
energy progressing east from the central-northern Plains will
amplify a bit (dig a bit farther south) upon reaching the Lower
MO-Mid MS Valleys) during this time as the ~600DM 500mb high
becomes centered farther west toward the Four Corners. There's near
to above average discrepancy amongst the global guidance (GFS most
vigorous with the deep-layer forcing and low-level moisture
transport) on where the heavy rain falls, and how much. A wet
solution with the likelihood of an MCS/upscale convective growth
within an area of expanding PWs of 2-2.25+ inches is within the
realm of possibility, given the ingredients expected. Could
certainly see a bump up to Slight Risk at some point, but for now
given the spread in the guidance, have opted to keep the inherited
Marginal Risk with cosmetic changes to better fit the most recent
QPF guidance.

...Central Gulf Coast Region into parts of the Southeast...
Heavy rainfall is expected along the New England cyclone's
trailing front near the FL/GA border. Moisture should be ample and
there could be enough effective bulk shear for convective
organization. The inherited Marginal Risk areas for Wednesday into
Thursday night saw only a few cosmetic changes to better fit the most recent QPF guidance.

Roth/Hurley

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!8HiMudIi0_WapK9eprYrtb8CxTx-PdRqDjPuHYhPFHunQOZOnuy4V9Xsjq2whgmekYzoZoOhxZrOT5sz-Up88g6eDd8$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!8HiMudIi0_WapK9eprYrtb8CxTx-PdRqDjPuHYhPFHunQOZOnuy4V9Xsjq2whgmekYzoZoOhxZrOT5sz-Up8M1LS_C8$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!8HiMudIi0_WapK9eprYrtb8CxTx-PdRqDjPuHYhPFHunQOZOnuy4V9Xsjq2whgmekYzoZoOhxZrOT5sz-Up8gZGHVuE$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Jul 27 00:39:48 2026

FOUS30 KWBC 270039
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
839 PM EDT Sun Jul 26 2026

Day 1
Valid 01Z Mon Jul 27 2026 - 12Z Mon Jul 27 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL IN & NEAR THE
LOWER SAVANNAH RIVER BASIN, WESTERN KENTUCKY, & MIDDLE TENNESSEE...

...South Carolina through the Atlantic coast of Florida...
Above average moisture remains over South Carolina into GA with
low level flow near a lingering quasi- stationary front continuing
to feed moisture into the area while poorly defined waves of low
pressure stretching across the base of an eastern U.S. trough
should focus/enhance the convection near coastal South
Carolina/Georgia early on. Maintained/trimmed Slight Risk based on
recent convective evolution and mesoscale guidance.

A Marginal Risk area extends southward through portions of the FL
Peninsula, with some uptick expected overnight into the early
morning. There is abundant deep- layer moisture in place as shown
by the 90+ percentile values of precipitable water which suggests
cells should be efficient rainfall producers with localized
rainfall rates in excess of 3 inches possible and rainfall totals
generally 2 to 4 inches.

...Four Corners States...
Monsoonal showers and thunderstorms appeared to have peaked for the
day and should be on decline this evening into tonight. Have
maintained the Marginal Risk to accommodate the ongoing activity.

...Portions of the Midwest-Upper Great Lakes-Lower Ohio Valley...
Progressive, organized activity has begun to develop within and
downwind of a highly unstable airmass (3000-6000 J/kg of ML CAPE)
which should continue overnight, particularly from the Lower Ohio
Valley through Middle TN into northernmost AL. The instability
gradient thunderstorms ride down should shift westward with time as
convection and related outflow boundaries slowly stabilize the
atmosphere. The concern is for embedded mesocyclones and cell
training bringing hourly rain amounts to 2.5" within an area of
modest flash flood guidance. Raising a Slight Risk on this update
to account for the developing scenario. Local totals could reach 6"
where cells repeat/training the longest. The upgrade to Slight
Risk was coordinated with the Memphis TN, Nashville TN, and
Huntsville AL forecast offices.

...North-central Virginia into central North Carolina...
Strong agreement among 18Z HREF/12z REFS guidance on lee-side
trough activity developing this evening over north-central VA under
a reinforcing impulse on the main trough axis over the Eastern
Seaboard. This activity shifts/propagates south ahead of the mid-
level impulse reaching central NC late tonight. PWs around 1.75",
ML CAPE of 1000+ J/kg, and effective bulk shear could allow for
hourly rain amounts to 2.5" where cells train or mesocyclones form.
Since coverage is not expected to be significant, left the risk
level as Marginal here.

Roth

Day 2
Valid 12Z Mon Jul 27 2026 - 12Z Tue Jul 28 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL ACROSS THE FOUR
CORNERS STATES ONTO THE CENTRAL PLAINS AND GREAT LAKES/OHIO VALLEY
INTO THE NORTHEAST...

...Four Corners States onto the Central Plains...
Center of upper high shifts south from CO to NM through tonight
which will direct more ridge topping diurnally-driven activity from
the central Rockies onto the central Plains on Monday compared to
today. Meanwhile continued monsoonal activity is expected across
the Four Corners states again. Favored focus areas for QPF are
again along the Mogollon Rim in AZ and in CO, though this time it's
east from the Continental Divide instead of west like today. Only
a minor expansion to the Marginal Risk is noted with the HREF
favoring central Plains activity into southwestern South Dakota.

...Great Lakes and Ohio Valley into the Northeast US...
A shortwave trough shifts southeast over northern Minnesota Monday
morning and through the Upper Great Lakes Monday
afternoon/evening. This is in northwest flow downstream of the
upper level ridge axis stalled over the western Dakota border.
Increasingly difluent flow ahead of the shortwave will lead to the consolidation/ strengthening of a low pressure system Monday night
which increases forcing for heavier rainfall over the Great
Lakes/Ohio Valley. The Marginal Risk was expanded west along the
WI/UP of MI border for morning activity, down through eastern IL
for downstream effects from tonight, and farther downstream into
New Jersey for Monday night activity beginning before it becomes
more significant on Tuesday.

...Tampa Bay...
Troughing currently on the east side of the FL Peninsula shifts to
the Gulf side tomorrow. Excellent agreement among 12Z HREF/REFS
guidance for repeating heavy thunderstorms across greater Tampa Bay
Monday morning into the afternoon. Consensus average QPF is 2-4"
with potential for 6" from both the HREF and RRFS. A Marginal Risk
for flash flooding is warranted in this scenario, especially for
urbanized drainage concerns.

Jackson

Day 3
Valid 12Z Tue Jul 28 2026 - 12Z Wed Jul 29 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR MUCH OF THE
NORTHERN MID-ATLANTIC INTO SOUTHERN NEW ENGLAND...

...Southern Appalachians into New England including northern Mid-
Atlantic...

Shortwave trough develops into a low pressure system over the
eastern Great Lakes Monday night that then stalls over interior
NY/PA Tuesday. There is greater certainly on the interior position
of this low which then maintains the warm sector over the northern
Mid-Atlantic coast into southern New England. 2 inch PW is
highlighted through this warm sector which should also have
sufficient instability for higher rainfall rates along with upper
divergence to promote growth and repeating activity. A Slight Risk
remains over the northern Mid-Atlantic into southern New England
with additional focus now for northern NJ, southern NY (inland of
NYC as of now) into western CT as a higher end slight (aka
"enhanced"). Areal average rainfall of 2-4" with locally higher
amounts is currently forecast for this "enhanced" area.

Elsewhere, warm sector moisture and instability is present down the Mid-Atlantic through North Carolina with potential for south moving
activity to repeat from reinforcing shortwaves rounding the new low
ot the north. Targeted Slight Risks may be warranted in the
southern Mid-Atlantic eventually. Otherwise, the 12Z QPF consensus
favored the southern Appalachians more than before, so they were
added to the Marginal Risk.

...Four Corners States across the Central Plains...
Further suppression of the upper high center south through New
Mexico opens further downstream activity from the Four Corners
states across the central Plains. The Marginal Risk was expanded
east to the KC metro. As of now the RRFS and EC-AIFS highlight the
High Plains of both northeast and southeast CO with more typical
Monsoonal activity over terrain in the Four Corners states.

Jackson

Day 4 and Day 5

Valid 12Z Wed Jul 29 2026 - 12Z Fri Jul 31 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
NORTHEAST WEDNESDAY...

...Northeast...
A dynamic coastal system takes shape Tue-Thu along/near the New
England Coast per model guidance. Strong upper level jet energy
upstream diving toward the trough base will amplify the upper
trough -- to the tune of 2+ standard deviations below late July
means at 500 mb-- which enhances the downstream QG forcing (upper diffluence/divergence and deep-layer ascent). Strengthening
east to south low-level flow will draw in moisture-rich air off
the Atlantic Gulf stream, with a swath of ~1.75" PWs within the
deepening TROWAL pivoting around the slow- moving comma head. Given
the persistence of favorable cool season dynamics with warm season thermodynamics (high deep- layer TPW/theta-e values), have
maintained the Day 4 Slight Risk area across parts of the
Northeast, which fits the most recent global guidance rather well.
Coordination with GYX/Gray ME and BTV/Burlington VT forecast
offices led to some restriction on its north and northeast side,
based on the 3-6 hourly FFGs.

Operational guidance shows 2-4" across the Slight Risk area on day
4/Wednesday into Wednesday night. Soundings will be moist, and
frontogenesis of the comma head could on its own lead to efficient
heavy rainfall; not much MU/ML CAPE will be necessary to lead
to flash flooding concerns. There has been a decided broadening
trend in the heavy rain signal since this time yesterday, and
depending on the degree of heavy rainfall that occurs on
Tuesday/Tuesday night, an upgrade to a Moderate somewhere in/near
the Sight Risk area can't be ruled out. Added a Marginal Risk for Thursday/Thursday night due to some signal for continued heavy
rainfall on day 5.

...Four Corners States into the Central/Northern Plains...
Monsoonal flow, likely to be enhanced by Genevieve moving offshore
Baja California, brings elevated moisture over the Desert
Southwest through the central Rockies and into the central and
northern Plains. The more suppressed ridge will allow multiple mesoscale/convectively aided shortwaves to push over the top/across
the Rockies into the Plains. The Marginal Risk area here only
needed some cosmetic changes to better fit the most recent QPF
guidance.

...Lower Missouri Valley into the Upper Mississippi Valley...
On Day 5 (Thursday-Thursday night), convectively-aided shortwave
energy progressing east from the central-northern Plains will
amplify a bit (dig a bit farther south) upon reaching the Lower
MO-Mid MS Valleys) during this time as the ~600DM 500mb high
becomes centered farther west toward the Four Corners. There's near
to above average discrepancy amongst the global guidance (GFS most
vigorous with the deep-layer forcing and low-level moisture
transport) on where the heavy rain falls, and how much. A wet
solution with the likelihood of an MCS/upscale convective growth
within an area of expanding PWs of 2-2.25+ inches is within the
realm of possibility, given the ingredients expected. Could
certainly see a bump up to Slight Risk at some point, but for now
given the spread in the guidance, have opted to keep the inherited
Marginal Risk with cosmetic changes to better fit the most recent
QPF guidance.

...Central Gulf Coast Region into parts of the Southeast...
Heavy rainfall is expected along the New England cyclone's
trailing front near the FL/GA border. Moisture should be ample and
there could be enough effective bulk shear for convective
organization. The inherited Marginal Risk areas for Wednesday into
Thursday night saw only a few cosmetic changes to better fit the most recent QPF guidance.

Roth/Hurley

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!_KNzo0FWybCcaZZkn7q2GspFdX8uyVFTd-_2QDdclvnfXIx8ogIzNzM_jRwoTovVOyto1JehZSezh71y-nUms8ZY3Pg$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!_KNzo0FWybCcaZZkn7q2GspFdX8uyVFTd-_2QDdclvnfXIx8ogIzNzM_jRwoTovVOyto1JehZSezh71y-nUmk3yqd80$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!_KNzo0FWybCcaZZkn7q2GspFdX8uyVFTd-_2QDdclvnfXIx8ogIzNzM_jRwoTovVOyto1JehZSezh71y-nUmyVPz1jA$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Jul 27 08:20:56 2026

FOUS30 KWBC 270820
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
420 AM EDT Mon Jul 27 2026

Day 1
Valid 12Z Mon Jul 27 2026 - 12Z Tue Jul 28 2026

...THERE ARE MARGINAL RISK OF EXCESSIVE RAINFALL AREAS ACROSS THE
FOUR CORNERS STATES ONTO THE CENTRAL PLAINS AND GREAT LAKES/OHIO
VALLEY INTO THE NORTHEAST...

...Four Corners States onto the Central Plains...
The center of an upper high will shift southward into New Mexico...which
will direct more ridge topping diurnally- driven activity from the
central Rockies onto the central Plains later today and through
much of the upcoming night. Favored focus areas for QPF are again
along the Mogollon Rim in Arizona north/east into Colorado. Only a
minor expansion to the Marginal Risk is noted with the HREF and
RRFS which would favor the central Plains activity into
southwestern South Dakota.

...Great Lakes and Ohio Valley into the Northeast US...
A shortwave that helped trigger convection over parts of the
Minnesota Arrowhead and nearby portions of northwestern Wisconsin
overnight leading into the the start of the Day 1 period at 27/12Z
will continue to shift towards the southeast across portions of the Upper
Great Lakes this afternoon and evening. This is in northwest flow
downstream of the upper level ridge axis stalled over the western
Dakotas. Increasingly difluent flow ahead of the shortwave will
lead to the consolidation and the strengthening of a low pressure
system later tonight...which in turn increases the forcing for
heavier rainfall over the Great Lakes/Ohio Valley. No major changes
were made to the Marginal Risk area,

...Tampa Bay...
Troughing occurs over the western side of the Florida peninsula
which shifts the focus for repeating thunderstorm with locally
heavy rainfall towards the greater Tampa Bay from later this
morning into the afternoon. Monday morning into the afternoon.
Consensus average QPF is 2-4" with potential for 6" from both the
HREF and RRFS. A Marginal Risk for flash flooding was maintained
especially due to urbanized drainage concerns.

Bann/Jackson

Day 2
Valid 12Z Tue Jul 28 2026 - 12Z Wed Jul 29 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR MUCH OF THE
NORTHERN MID-ATLANTIC INTO SOUTHERN NEW ENGLAND...

...Southern Appalachians into New England including northern Mid-
Atlantic...

The amplification of a mid- and upper-level trough moving out of
the Great Lakes/Ohio Valley on Monday leads to the development of
surface low pressure over the eastern Great Lakes by the start of
the Day 2 period. However...the low stalls over interior NY/PA on
Tuesday. There is has been growing certainly on the interior
position of this low which then maintains the warm sector over the
northern Mid-Atlantic coast into southern New England. Precipitable
water values of 2 inches is highlighted through this warm sector
which should also have sufficient instability for higher rainfall
rates along with divergence aloft to promote growth and repeating
activity. A Slight Risk remains over the northern Mid-Atlantic
into southern New England with additional focus now across parts of
northern New Jersey into southern New York (inland of New York
City) into western Connecticut considered to be higher-end Slight.

Elsewhere, warm sector moisture and instability is present down
the Mid-Atlantic through North Carolina with potential for south
moving activity to repeat from reinforcing shortwaves rounding the
new low ot the north.

...Four Corners States across the Central Plains...
Further suppression of the upper high center south through New
Mexico opens the opportunity for additional downstream activity
from the Four Corners states across the central Plains. The
Marginal Risk was expanded east to the KC metro. The RRFS still
highlighted the High Plains of both northeast and southeast
Colorado with more typical Monsoonal activity over terrain in the
Four Corners states.

Bann/Jackson

Day 3
Valid 12Z Wed Jul 29 2026 - 12Z Thu Jul 30 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE NORTHEAST WEDNESDAY...

...Northeast...
A dynamic coastal system takes earlier in the week along/near the
New England Coast per model guidance. Strong upper level jet
energy upstream diving toward the trough base will amplify the
upper trough -- to the tune of 2+ standard deviations below late
July means at 500 mb-- which enhances the downstream QG forcing as
it encounters deep moisture at low- to mid-levels being drawn in
from the Atlantic Gulf stream, with a swath of ~1.75" PWs. As
previously noted...given the persistence of favorable cool season
dynamics with warm season thermodynamics (high deep- layer
TPW/theta-e values), have maintained the Slight Risk area pretty
much unchanged across parts of the Northeast, which fits the most
recent global guidance rather well.

Operational guidance shows 2-4 inches of rainfall across the
Slight Risk area from Wednesday into late Wednesday night/early
Thursday morning. Frontogenesis of the comma head could on its own
lead to efficient heavy rainfall; not much MU/ML CAPE will be
necessary to lead to flash flooding concerns.

...Four Corners States into the Central/Northern Plains...
Monsoonal flow, likely to be enhanced by Genevieve moving offshore
Baja California, brings elevated moisture over the Desert
Southwest through the central Rockies and into the central and
northern Plains. The more suppressed ridge will allow multiple mesoscale/convectively aided shortwaves to push over the top/across
the Rockies into the Plains. The Marginal Risk area here only
needed some cosmetic changes to better fit the most recent QPF
guidance but the differences did not reflect a change in the
forecast reasoning.

...Central Gulf Coast Region into parts of the Southeast...
Numerical guidance continued to show heavy...to potentially excessive...rainfall being forced/focused by a cold front
associated with the cyclone impacting New England. Still little
reason to question whether the moisture will be ample at the same
time that the effective bulk shear is sufficient for convective
organization. The inherited Marginal Risk areas for Wednesday into
Thursday night saw only a few cosmetic changes to better fit the
most recent QPF guidance.

Bann/Roth

Day 4 and Day 5

Valid 12Z Thu Jul 30 2026 - 12Z Sat Aug 01 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE LOWER MISSOURI AND MID TO UPPER MISSISSIPPI VALLEY...

...Lower Missouri Valley into the Mid-Upper Mississippi Valley...
On Day 4 (Thursday-Thursday night), convectively-aided shortwave
energy progressing east from the central-northern Plains will
amplify a bit (dig a bit farther south) upon reaching the Lower MO-
Mid MS Valleys) during this time as the ~600DM 500mb high becomes
centered farther west toward the Four Corners. There's near to
above average discrepancy amongst the 00Z global guidance. The GFS/
GEFS mean/AIGFS are a bit farther east compared to the ECMWF/ECENS
mean/EC AIFS, with the CMC camp basically in the middle in terms of
eastward progression. In addition, there remains latitudinal
differences with the heaviest QPF, with the 00Z UKMet the farthest
north. Given the MCS/upscale growth potential with this system,
considering the influx of 2-2.25+ PWs per the guidance,
concentrated areas of heavy rain are expected, especially across
the Corn Belt given the deep-layer moisture profile and high
surface dewpoints. Certainly an event that would warrant a Slight
Risk, which for now we've confined across eastern SD, far eastern
NE and northeast KS, into northwest MO, western 2/3 of Iowa, and
southern MN, where the global ensemble probabilities of >3" in
12/24 hours are highest.

On Day 5 (Friday-Friday night), have essentially shifted the
Slight Risk area farther downstream (east-southeast) per the global
guidance consensus. Globals all show spotty heavy 24hr rainfall
totals, i.e. 3-5+ inches, though again with some spatial spread in
the guidance. ECENS QPF exceedance probabilities have come up from
the previous run, and are certainly higher compared to the day 4
period (more expanded area of 3 to 5 inch probabilities).

...Four Corners States into the Central/Northern Plains...
Monsoonal flow and anomalous deep-layer moisture will maintain a
Marginal (isolated) excessive rainfall risk over eastern AZ and
much of MN (except SE portion) into southeast UT and through much
of CO. The expanding mid/upper level ridge (600dm heights at 500
mb) will likely limit the coverage compared to recent days,
especially by Friday.

...Central Gulf Coast Region into parts of the Southeast...
Heavy rainfall is expected along the New England cyclone's
trailing front near the FL/GA border. Moisture should be ample and
there could be enough effective bulk shear for convective
organization. The inherited Marginal Risk areas for Thursday into
Friday night saw only a few cosmetic changes to better fit the
most recent QPF guidance.

Hurley

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!7-ccpt5o0AT_3Pq_QU7wk9fbSJ-L9Y4OwJr2E1RH8woFGPkut95jrBz9Wm9_jh9hfrqjSXe-5Z2j5c8mrc_pHO6l4DY$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!7-ccpt5o0AT_3Pq_QU7wk9fbSJ-L9Y4OwJr2E1RH8woFGPkut95jrBz9Wm9_jh9hfrqjSXe-5Z2j5c8mrc_pHpQ2SVk$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!7-ccpt5o0AT_3Pq_QU7wk9fbSJ-L9Y4OwJr2E1RH8woFGPkut95jrBz9Wm9_jh9hfrqjSXe-5Z2j5c8mrc_p3FWV7us$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Jul 27 15:52:54 2026

FOUS30 KWBC 271552
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1152 AM EDT Mon Jul 27 2026

Day 1
Valid 16Z Mon Jul 27 2026 - 12Z Tue Jul 28 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE FOUR CORNERS STATES THROUGH THE CENTRAL PLAINS, THE GREAT
LAKES/OHIO VALLEY, THE COASTAL MID-ATLANTIC STATES, AND THE WESTERN
FLORIDA PENINSULA INTO THE KEYS...

...Four Corners States onto the Central Plains...
The monsoon ridge gets slightly suppressed south today by
shortwaves cresting its periphery over the Northern Rockies. This
will squelch the higher PW a bit south from previous days, but
otherwise the ridge remains in place with weak impulses rotating
around it to enhance ascent and resulting convection. Once again,
the focus for thunderstorm development will be across the higher
terrain late this morning, before expanding across the Four Corners
states, with some organization possible through 20-30 kts of bulk
shear. While PWs will still be +1 to +2 sigma from AZ through WY,
the most impressive CAPE (approaching 750 J/kg) look to be confined
to AZ/NM, which can be a better discriminator for excessive
rainfall potential within the monsoon. However, any convection has
the potential to produce intense rain rates leading to hourly
rainfall of 1-1.5", which could produce at least isolated flash
flood responses over vulnerable terrain features or burn scars.

Storms that develop across UT/WY/CO may feature faster forward
propagation (after brief slow downs during initiation) so the MRGL
risk was expanded slightly into the Central Plains. However, this
faster motion should at least somewhat limit the runoff potential.
Farther south into AZ a shortwave moving along the Mexico/Arizona
border within the elevated shear may help organized clusters of
storms moving more slowly westward, and this is reflected by
elevated (but still modest) probabilities for 3" of rain today.
Considered a targeted SLGT risk for the TWC CWA but simulated
reflectivity from the CAMs and the UA WRF were not sufficient for
an upgrade at this time.

...Great Lakes and Ohio Valley into the Northeast US...
A potent shortwave diving out of Ontario across the Great Lakes
will interact with a complex surface pattern over the region to
drive scattered to widespread thunderstorms through the day.
Activity this morning is already producing heavy rainfall rates
measured via MRMS of over 1"/hr within the pronounced ascent as it
impinges upon an impressive overlap of PW/CAPE measured via morning
12Z soundings at APX/GRB of near record values (1.7-2.1 PWs and
4000-5000 J/Kg CAPE). As the aftn progresses, convection will
become increasingly widespread as the shortwave dives south and
pushes a cold front (and accompanying wave of low pressure) through
the Great Lakes and southeast towards the Ohio Valley/Central
Appalachians). While the thermodynamic environment will support
intense rain rates within any thunderstorms today, and 40-50kts of
bulk shear will help organize storms into clusters and/or
supercells, mean winds of 30-40 kts suggest convection will remain
progressive, and Corfidi vectors do not support much
backbuilding/training. So while local impacts due to flash flooding
are possible, the overall risk matches best the MRGL risk category
so the inherited was changed only cosmetically for new guidance.

...Western Florida Panhandle...
Weak shortwave diving along or just west of the Florida Peninsula
will work together with broad directional jet- level diffluence to
spawn repeated rounds of thunderstorm activity today. This
convection will occur within robust PW anomalies reaching +1.5 to
+2.0 sigma for the southern half of Florida, which when combined
with SBCAPE exceeding 3000 J/kg will support torrential rain rates.
While shear will be minimal indicating pulse-type convection, weak
flow and resulting cell collisions or outflow mergers, as well as
the Gulf breeze, will support scattered to widespread
thunderstorms, all of which may contain 2-3"/hr rainfall. Due to
the nature of this convection, placing the axis of heaviest amounts
remains uncertain, but there is a common signal in both REFS and
HREF probabilities for locally more than 5" (20-40% chance) near
Tampa Bay, so the inherited MRGL risk was continued for this area,
but expanded along the coast for potential beneath the forcing
created by the upper diffluence, and added the Florida Keys after
coordination with WFO KEY.

...Coastal Mid-Atlantic...
A surface trough will sharpen east of I-95 this aftn providing a
focus for ascent and convective development. The high-res CAMs
suggest development will generally be isolated, but within
favorable thermodynamics characterized by PWs above 1.5 inches and
SBCAPE of 2000 J/kg or more. This will support intense rain rates
within any storms that develop, and both the REFS and HREF
neighborhood probabilities reach 50-70% for hourly rainfall of 1
inch or more. While there is some uncertainty into the coverage and
placement of activity this aftn, the inherited MRGL risk was
continued with just subtle cosmetic modifications since soils are
saturated from heavy antecedent rainfall.

Weiss

Day 2
Valid 12Z Tue Jul 28 2026 - 12Z Wed Jul 29 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR MUCH OF THE
NORTHERN MID-ATLANTIC INTO SOUTHERN NEW ENGLAND...

...Southern Appalachians into New England including northern Mid-
Atlantic...

The amplification of a mid- and upper-level trough moving out of
the Great Lakes/Ohio Valley on Monday leads to the development of
surface low pressure over the eastern Great Lakes by the start of
the Day 2 period. However...the low stalls over interior NY/PA on
Tuesday. There is has been growing certainly on the interior
position of this low which then maintains the warm sector over the
northern Mid-Atlantic coast into southern New England. Precipitable
water values of 2 inches is highlighted through this warm sector
which should also have sufficient instability for higher rainfall
rates along with divergence aloft to promote growth and repeating
activity. A Slight Risk remains over the northern Mid-Atlantic
into southern New England with additional focus now across parts of
northern New Jersey into southern New York (inland of New York
City) into western Connecticut considered to be higher-end Slight.

Elsewhere, warm sector moisture and instability is present down
the Mid-Atlantic through North Carolina with potential for south
moving activity to repeat from reinforcing shortwaves rounding the
new low ot the north.

...Four Corners States across the Central Plains...
Further suppression of the upper high center south through New
Mexico opens the opportunity for additional downstream activity
from the Four Corners states across the central Plains. The
Marginal Risk was expanded east to the KC metro. The RRFS still
highlighted the High Plains of both northeast and southeast
Colorado with more typical Monsoonal activity over terrain in the
Four Corners states.

Bann/Jackson

Day 3
Valid 12Z Wed Jul 29 2026 - 12Z Thu Jul 30 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE NORTHEAST WEDNESDAY...

...Northeast...
A dynamic coastal system takes earlier in the week along/near the
New England Coast per model guidance. Strong upper level jet
energy upstream diving toward the trough base will amplify the
upper trough -- to the tune of 2+ standard deviations below late
July means at 500 mb-- which enhances the downstream QG forcing as
it encounters deep moisture at low- to mid-levels being drawn in
from the Atlantic Gulf stream, with a swath of ~1.75" PWs. As
previously noted...given the persistence of favorable cool season
dynamics with warm season thermodynamics (high deep- layer
TPW/theta-e values), have maintained the Slight Risk area pretty
much unchanged across parts of the Northeast, which fits the most
recent global guidance rather well.

Operational guidance shows 2-4 inches of rainfall across the
Slight Risk area from Wednesday into late Wednesday night/early
Thursday morning. Frontogenesis of the comma head could on its own
lead to efficient heavy rainfall; not much MU/ML CAPE will be
necessary to lead to flash flooding concerns.

...Four Corners States into the Central/Northern Plains...
Monsoonal flow, likely to be enhanced by Genevieve moving offshore
Baja California, brings elevated moisture over the Desert
Southwest through the central Rockies and into the central and
northern Plains. The more suppressed ridge will allow multiple mesoscale/convectively aided shortwaves to push over the top/across
the Rockies into the Plains. The Marginal Risk area here only
needed some cosmetic changes to better fit the most recent QPF
guidance but the differences did not reflect a change in the
forecast reasoning.

...Central Gulf Coast Region into parts of the Southeast...
Numerical guidance continued to show heavy...to potentially excessive...rainfall being forced/focused by a cold front
associated with the cyclone impacting New England. Still little
reason to question whether the moisture will be ample at the same
time that the effective bulk shear is sufficient for convective
organization. The inherited Marginal Risk areas for Wednesday into
Thursday night saw only a few cosmetic changes to better fit the
most recent QPF guidance.

Bann/Roth

Day 4 and Day 5

Valid 12Z Thu Jul 30 2026 - 12Z Sat Aug 01 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE LOWER MISSOURI AND MID TO UPPER MISSISSIPPI VALLEY...

...Lower Missouri Valley into the Mid-Upper Mississippi Valley...
On Day 4 (Thursday-Thursday night), convectively-aided shortwave
energy progressing east from the central-northern Plains will
amplify a bit (dig a bit farther south) upon reaching the Lower MO-
Mid MS Valleys) during this time as the ~600DM 500mb high becomes
centered farther west toward the Four Corners. There's near to
above average discrepancy amongst the 00Z global guidance. The GFS/
GEFS mean/AIGFS are a bit farther east compared to the ECMWF/ECENS
mean/EC AIFS, with the CMC camp basically in the middle in terms of
eastward progression. In addition, there remains latitudinal
differences with the heaviest QPF, with the 00Z UKMet the farthest
north. Given the MCS/upscale growth potential with this system,
considering the influx of 2-2.25+ PWs per the guidance,
concentrated areas of heavy rain are expected, especially across
the Corn Belt given the deep-layer moisture profile and high
surface dewpoints. Certainly an event that would warrant a Slight
Risk, which for now we've confined across eastern SD, far eastern
NE and northeast KS, into northwest MO, western 2/3 of Iowa, and
southern MN, where the global ensemble probabilities of >3" in
12/24 hours are highest.

On Day 5 (Friday-Friday night), have essentially shifted the
Slight Risk area farther downstream (east-southeast) per the global
guidance consensus. Globals all show spotty heavy 24hr rainfall
totals, i.e. 3-5+ inches, though again with some spatial spread in
the guidance. ECENS QPF exceedance probabilities have come up from
the previous run, and are certainly higher compared to the day 4
period (more expanded area of 3 to 5 inch probabilities).

...Four Corners States into the Central/Northern Plains...
Monsoonal flow and anomalous deep-layer moisture will maintain a
Marginal (isolated) excessive rainfall risk over eastern AZ and
much of MN (except SE portion) into southeast UT and through much
of CO. The expanding mid/upper level ridge (600dm heights at 500
mb) will likely limit the coverage compared to recent days,
especially by Friday.

...Central Gulf Coast Region into parts of the Southeast...
Heavy rainfall is expected along the New England cyclone's
trailing front near the FL/GA border. Moisture should be ample and
there could be enough effective bulk shear for convective
organization. The inherited Marginal Risk areas for Thursday into
Friday night saw only a few cosmetic changes to better fit the
most recent QPF guidance.

Hurley

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!83s-wBwdH2tbxPzxrh6J_I3bKvRikbic3kIYkKVFYJXHRLsZcRR95SHgG80XyTHWvn7T0WOtE6y0uaKfBQ_TQ2COX7U$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!83s-wBwdH2tbxPzxrh6J_I3bKvRikbic3kIYkKVFYJXHRLsZcRR95SHgG80XyTHWvn7T0WOtE6y0uaKfBQ_Tb1xG9OM$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!83s-wBwdH2tbxPzxrh6J_I3bKvRikbic3kIYkKVFYJXHRLsZcRR95SHgG80XyTHWvn7T0WOtE6y0uaKfBQ_T3QT0jvo$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Jul 27 16:05:28 2026

FOUS30 KWBC 271605
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1205 PM EDT Mon Jul 27 2026

Day 1
Valid 16Z Mon Jul 27 2026 - 12Z Tue Jul 28 2026

...THERE ARE MARGINAL RISKS OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE FOUR CORNERS STATES THROUGH THE CENTRAL PLAINS, THE GREAT
LAKES/OHIO VALLEY, THE COASTAL MID-ATLANTIC STATES, AND THE WESTERN
FLORIDA PENINSULA INTO THE KEYS...

...Four Corners States onto the Central Plains...
The monsoon ridge gets slightly suppressed south today by
shortwaves cresting its periphery over the Northern Rockies. This
will squelch the higher PW a bit south from previous days, but
otherwise the ridge remains in place with weak impulses rotating
around it to enhance ascent and resulting convection. Once again,
the focus for thunderstorm development will be across the higher
terrain late this morning, before expanding across the Four Corners
states, with some organization possible through 20-30 kts of bulk
shear. While PWs will still be +1 to +2 sigma from AZ through WY,
the most impressive CAPE (approaching 750 J/kg) look to be confined
to AZ/NM, which can be a better discriminator for excessive
rainfall potential within the monsoon. However, any convection has
the potential to produce intense rain rates leading to hourly
rainfall of 1-1.5", which could produce at least isolated flash
flood responses over vulnerable terrain features or burn scars.

Storms that develop across UT/WY/CO may feature faster forward
propagation (after brief slow downs during initiation) so the MRGL
risk was expanded slightly into the Central Plains. However, this
faster motion should at least somewhat limit the runoff potential.
Farther south into AZ a shortwave moving along the Mexico/Arizona
border within the elevated shear may help organized clusters of
storms moving more slowly westward, and this is reflected by
elevated (but still modest) probabilities for 3" of rain today.
Considered a targeted SLGT risk for the TWC CWA but simulated
reflectivity from the CAMs and the UA WRF were not sufficient for
an upgrade at this time.

...Great Lakes and Ohio Valley into the Northeast US...
A potent shortwave diving out of Ontario across the Great Lakes
will interact with a complex surface pattern over the region to
drive scattered to widespread thunderstorms through the day.
Activity this morning is already producing heavy rainfall rates
measured via MRMS of over 1"/hr within the pronounced ascent as it
impinges upon an impressive overlap of PW/CAPE measured via morning
12Z soundings at APX/GRB of near record values (1.7-2.1 PWs and
4000-5000 J/Kg CAPE). As the aftn progresses, convection will
become increasingly widespread as the shortwave dives south and
pushes a cold front (and accompanying wave of low pressure) through
the Great Lakes and southeast towards the Ohio Valley/Central
Appalachians). While the thermodynamic environment will support
intense rain rates within any thunderstorms today, and 40-50kts of
bulk shear will help organize storms into clusters and/or
supercells, mean winds of 30-40 kts suggest convection will remain
progressive, and Corfidi vectors do not support much
backbuilding/training. So while local impacts due to flash flooding
are possible, the overall risk matches best the MRGL risk category
so the inherited was changed only cosmetically for new guidance.

...Western Florida Peninsula...
Weak shortwave diving along or just west of the Florida Peninsula
will work together with broad directional jet- level diffluence to
spawn repeated rounds of thunderstorm activity today. This
convection will occur within robust PW anomalies reaching +1.5 to
+2.0 sigma for the southern half of Florida, which when combined
with SBCAPE exceeding 3000 J/kg will support torrential rain rates.
While shear will be minimal indicating pulse-type convection, weak
flow and resulting cell collisions or outflow mergers, as well as
the Gulf breeze, will support scattered to widespread
thunderstorms, all of which may contain 2-3"/hr rainfall. Due to
the nature of this convection, placing the axis of heaviest amounts
remains uncertain, but there is a common signal in both REFS and
HREF probabilities for locally more than 5" (20-40% chance) near
Tampa Bay, so the inherited MRGL risk was continued for this area,
but expanded along the coast for potential beneath the forcing
created by the upper diffluence, and added the Florida Keys after
coordination with WFO KEY.

...Coastal Mid-Atlantic...
A surface trough will sharpen east of I-95 this aftn providing a
focus for ascent and convective development. The high-res CAMs
suggest development will generally be isolated, but within
favorable thermodynamics characterized by PWs above 1.5 inches and
SBCAPE of 2000 J/kg or more. This will support intense rain rates
within any storms that develop, and both the REFS and HREF
neighborhood probabilities reach 50-70% for hourly rainfall of 1
inch or more. While there is some uncertainty into the coverage and
placement of activity this aftn, the inherited MRGL risk was
continued with just subtle cosmetic modifications since soils are
saturated from heavy antecedent rainfall.

Weiss

Day 2
Valid 12Z Tue Jul 28 2026 - 12Z Wed Jul 29 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR MUCH OF THE
NORTHERN MID-ATLANTIC INTO SOUTHERN NEW ENGLAND...

...Southern Appalachians into New England including northern Mid-
Atlantic...

The amplification of a mid- and upper-level trough moving out of
the Great Lakes/Ohio Valley on Monday leads to the development of
surface low pressure over the eastern Great Lakes by the start of
the Day 2 period. However...the low stalls over interior NY/PA on
Tuesday. There is has been growing certainly on the interior
position of this low which then maintains the warm sector over the
northern Mid-Atlantic coast into southern New England. Precipitable
water values of 2 inches is highlighted through this warm sector
which should also have sufficient instability for higher rainfall
rates along with divergence aloft to promote growth and repeating
activity. A Slight Risk remains over the northern Mid-Atlantic
into southern New England with additional focus now across parts of
northern New Jersey into southern New York (inland of New York
City) into western Connecticut considered to be higher-end Slight.

Elsewhere, warm sector moisture and instability is present down
the Mid-Atlantic through North Carolina with potential for south
moving activity to repeat from reinforcing shortwaves rounding the
new low ot the north.

...Four Corners States across the Central Plains...
Further suppression of the upper high center south through New
Mexico opens the opportunity for additional downstream activity
from the Four Corners states across the central Plains. The
Marginal Risk was expanded east to the KC metro. The RRFS still
highlighted the High Plains of both northeast and southeast
Colorado with more typical Monsoonal activity over terrain in the
Four Corners states.

Bann/Jackson

Day 3
Valid 12Z Wed Jul 29 2026 - 12Z Thu Jul 30 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE NORTHEAST WEDNESDAY...

...Northeast...
A dynamic coastal system takes earlier in the week along/near the
New England Coast per model guidance. Strong upper level jet
energy upstream diving toward the trough base will amplify the
upper trough -- to the tune of 2+ standard deviations below late
July means at 500 mb-- which enhances the downstream QG forcing as
it encounters deep moisture at low- to mid-levels being drawn in
from the Atlantic Gulf stream, with a swath of ~1.75" PWs. As
previously noted...given the persistence of favorable cool season
dynamics with warm season thermodynamics (high deep- layer
TPW/theta-e values), have maintained the Slight Risk area pretty
much unchanged across parts of the Northeast, which fits the most
recent global guidance rather well.

Operational guidance shows 2-4 inches of rainfall across the
Slight Risk area from Wednesday into late Wednesday night/early
Thursday morning. Frontogenesis of the comma head could on its own
lead to efficient heavy rainfall; not much MU/ML CAPE will be
necessary to lead to flash flooding concerns.

...Four Corners States into the Central/Northern Plains...
Monsoonal flow, likely to be enhanced by Genevieve moving offshore
Baja California, brings elevated moisture over the Desert
Southwest through the central Rockies and into the central and
northern Plains. The more suppressed ridge will allow multiple mesoscale/convectively aided shortwaves to push over the top/across
the Rockies into the Plains. The Marginal Risk area here only
needed some cosmetic changes to better fit the most recent QPF
guidance but the differences did not reflect a change in the
forecast reasoning.

...Central Gulf Coast Region into parts of the Southeast...
Numerical guidance continued to show heavy...to potentially excessive...rainfall being forced/focused by a cold front
associated with the cyclone impacting New England. Still little
reason to question whether the moisture will be ample at the same
time that the effective bulk shear is sufficient for convective
organization. The inherited Marginal Risk areas for Wednesday into
Thursday night saw only a few cosmetic changes to better fit the
most recent QPF guidance.

Bann/Roth

Day 4 and Day 5

Valid 12Z Thu Jul 30 2026 - 12Z Sat Aug 01 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE LOWER MISSOURI AND MID TO UPPER MISSISSIPPI VALLEY...

...Lower Missouri Valley into the Mid-Upper Mississippi Valley...
On Day 4 (Thursday-Thursday night), convectively-aided shortwave
energy progressing east from the central-northern Plains will
amplify a bit (dig a bit farther south) upon reaching the Lower MO-
Mid MS Valleys) during this time as the ~600DM 500mb high becomes
centered farther west toward the Four Corners. There's near to
above average discrepancy amongst the 00Z global guidance. The GFS/
GEFS mean/AIGFS are a bit farther east compared to the ECMWF/ECENS
mean/EC AIFS, with the CMC camp basically in the middle in terms of
eastward progression. In addition, there remains latitudinal
differences with the heaviest QPF, with the 00Z UKMet the farthest
north. Given the MCS/upscale growth potential with this system,
considering the influx of 2-2.25+ PWs per the guidance,
concentrated areas of heavy rain are expected, especially across
the Corn Belt given the deep-layer moisture profile and high
surface dewpoints. Certainly an event that would warrant a Slight
Risk, which for now we've confined across eastern SD, far eastern
NE and northeast KS, into northwest MO, western 2/3 of Iowa, and
southern MN, where the global ensemble probabilities of >3" in
12/24 hours are highest.

On Day 5 (Friday-Friday night), have essentially shifted the
Slight Risk area farther downstream (east-southeast) per the global
guidance consensus. Globals all show spotty heavy 24hr rainfall
totals, i.e. 3-5+ inches, though again with some spatial spread in
the guidance. ECENS QPF exceedance probabilities have come up from
the previous run, and are certainly higher compared to the day 4
period (more expanded area of 3 to 5 inch probabilities).

...Four Corners States into the Central/Northern Plains...
Monsoonal flow and anomalous deep-layer moisture will maintain a
Marginal (isolated) excessive rainfall risk over eastern AZ and
much of MN (except SE portion) into southeast UT and through much
of CO. The expanding mid/upper level ridge (600dm heights at 500
mb) will likely limit the coverage compared to recent days,
especially by Friday.

...Central Gulf Coast Region into parts of the Southeast...
Heavy rainfall is expected along the New England cyclone's
trailing front near the FL/GA border. Moisture should be ample and
there could be enough effective bulk shear for convective
organization. The inherited Marginal Risk areas for Thursday into
Friday night saw only a few cosmetic changes to better fit the
most recent QPF guidance.

Hurley

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!-zFlT_1KfDjYIGfiU5Q8ghqLuKylP29L94YVftYVdwsJrYtQDFhNVjx6mVP7j0jSgI5pY3uNLzb7N2Y6pgx8h_y8c_4$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!-zFlT_1KfDjYIGfiU5Q8ghqLuKylP29L94YVftYVdwsJrYtQDFhNVjx6mVP7j0jSgI5pY3uNLzb7N2Y6pgx8sodVKXM$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!-zFlT_1KfDjYIGfiU5Q8ghqLuKylP29L94YVftYVdwsJrYtQDFhNVjx6mVP7j0jSgI5pY3uNLzb7N2Y6pgx8PYzilfE$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Jul 27 18:57:26 2026

FOUS30 KWBC 271857
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
257 PM EDT Mon Jul 27 2026

Day 1
Valid 1832Z Mon Jul 27 2026 - 12Z Tue Jul 28 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL IN EFFECT FOR PARTS
OF SOUTHEAST WISCONSIN, NORTHEAST/EAST-CENTRAL ILLINOIS, AND NORTHWEST/WEST-CENTRAL INDIANA...

1830Z Special Update...
A SLGT Risk was added to parts of the Midwest from SE WI through
much of NE IL and NW IN, including the Chicago, Indianapolis, and
Milwaukee metro regions. This is due to ongoing heavy rainfall and
the expectation for intense rainfall rates to continue for several
hours while the threat slides southward with time. Both 17z runs
of the HRRR and RRFS support 2-5" additional rainfall amounts
through 06z, which would produce scattered areas of flash flooding.
Urban locations could see significant street flooding should
thunderstorms train over the region. As the complex pushes
southward this evening and overnight across central and southern
IL/IN, rainfall rates and the threat of backbuilding storms should
diminish as better forcing shifts eastward into the upper Ohio
Valley. See MPD 0861 for more information.

Snell

Previous Discussion...

...Four Corners States onto the Central Plains...
The monsoon ridge gets slightly suppressed south today by
shortwaves cresting its periphery over the Northern Rockies. This
will squelch the higher PW a bit south from previous days, but
otherwise the ridge remains in place with weak impulses rotating
around it to enhance ascent and resulting convection. Once again,
the focus for thunderstorm development will be across the higher
terrain late this morning, before expanding across the Four Corners
states, with some organization possible through 20-30 kts of bulk
shear. While PWs will still be +1 to +2 sigma from AZ through WY,
the most impressive CAPE (approaching 750 J/kg) look to be confined
to AZ/NM, which can be a better discriminator for excessive
rainfall potential within the monsoon. However, any convection has
the potential to produce intense rain rates leading to hourly
rainfall of 1-1.5", which could produce at least isolated flash
flood responses over vulnerable terrain features or burn scars.

Storms that develop across UT/WY/CO may feature faster forward
propagation (after brief slow downs during initiation) so the MRGL
risk was expanded slightly into the Central Plains. However, this
faster motion should at least somewhat limit the runoff potential.
Farther south into AZ a shortwave moving along the Mexico/Arizona
border within the elevated shear may help organized clusters of
storms moving more slowly westward, and this is reflected by
elevated (but still modest) probabilities for 3" of rain today.
Considered a targeted SLGT risk for the TWC CWA but simulated
reflectivity from the CAMs and the UA WRF were not sufficient for
an upgrade at this time.

...Great Lakes and Ohio Valley into the Northeast US...
A potent shortwave diving out of Ontario across the Great Lakes
will interact with a complex surface pattern over the region to
drive scattered to widespread thunderstorms through the day.
Activity this morning is already producing heavy rainfall rates
measured via MRMS of over 1"/hr within the pronounced ascent as it
impinges upon an impressive overlap of PW/CAPE measured via morning
12Z soundings at APX/GRB of near record values (1.7-2.1 PWs and
4000-5000 J/Kg CAPE). As the aftn progresses, convection will
become increasingly widespread as the shortwave dives south and
pushes a cold front (and accompanying wave of low pressure) through
the Great Lakes and southeast towards the Ohio Valley/Central
Appalachians). While the thermodynamic environment will support
intense rain rates within any thunderstorms today, and 40-50kts of
bulk shear will help organize storms into clusters and/or
supercells, mean winds of 30-40 kts suggest convection will remain
progressive, and Corfidi vectors do not support much
backbuilding/training. So while local impacts due to flash flooding
are possible, the overall risk matches best the MRGL risk category
so the inherited was changed only cosmetically for new guidance.

...Western Florida Peninsula...
Weak shortwave diving along or just west of the Florida Peninsula
will work together with broad directional jet- level diffluence to
spawn repeated rounds of thunderstorm activity today. This
convection will occur within robust PW anomalies reaching +1.5 to
+2.0 sigma for the southern half of Florida, which when combined
with SBCAPE exceeding 3000 J/kg will support torrential rain rates.
While shear will be minimal indicating pulse-type convection, weak
flow and resulting cell collisions or outflow mergers, as well as
the Gulf breeze, will support scattered to widespread
thunderstorms, all of which may contain 2-3"/hr rainfall. Due to
the nature of this convection, placing the axis of heaviest amounts
remains uncertain, but there is a common signal in both REFS and
HREF probabilities for locally more than 5" (20-40% chance) near
Tampa Bay, so the inherited MRGL risk was continued for this area,
but expanded along the coast for potential beneath the forcing
created by the upper diffluence, and added the Florida Keys after
coordination with WFO KEY.

...Coastal Mid-Atlantic...
A surface trough will sharpen east of I-95 this aftn providing a
focus for ascent and convective development. The high-res CAMs
suggest development will generally be isolated, but within
favorable thermodynamics characterized by PWs above 1.5 inches and
SBCAPE of 2000 J/kg or more. This will support intense rain rates
within any storms that develop, and both the REFS and HREF
neighborhood probabilities reach 50-70% for hourly rainfall of 1
inch or more. While there is some uncertainty into the coverage and
placement of activity this aftn, the inherited MRGL risk was
continued with just subtle cosmetic modifications since soils are
saturated from heavy antecedent rainfall.

Weiss

Day 2
Valid 12Z Tue Jul 28 2026 - 12Z Wed Jul 29 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR MUCH OF THE
NORTHERN MID-ATLANTIC INTO SOUTHERN NEW ENGLAND...

...Southern Appalachians into New England including northern Mid-
Atlantic...

The amplification of a mid- and upper-level trough moving out of
the Great Lakes/Ohio Valley on Monday leads to the development of
surface low pressure over the eastern Great Lakes by the start of
the Day 2 period. However...the low stalls over interior NY/PA on
Tuesday. There is has been growing certainly on the interior
position of this low which then maintains the warm sector over the
northern Mid-Atlantic coast into southern New England. Precipitable
water values of 2 inches is highlighted through this warm sector
which should also have sufficient instability for higher rainfall
rates along with divergence aloft to promote growth and repeating
activity. A Slight Risk remains over the northern Mid-Atlantic
into southern New England with additional focus now across parts of
northern New Jersey into southern New York (inland of New York
City) into western Connecticut considered to be higher-end Slight.

Elsewhere, warm sector moisture and instability is present down
the Mid-Atlantic through North Carolina with potential for south
moving activity to repeat from reinforcing shortwaves rounding the
new low ot the north.

...Four Corners States across the Central Plains...
Further suppression of the upper high center south through New
Mexico opens the opportunity for additional downstream activity
from the Four Corners states across the central Plains. The
Marginal Risk was expanded east to the KC metro. The RRFS still
highlighted the High Plains of both northeast and southeast
Colorado with more typical Monsoonal activity over terrain in the
Four Corners states.

Bann/Jackson

Day 3
Valid 12Z Wed Jul 29 2026 - 12Z Thu Jul 30 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE NORTHEAST WEDNESDAY...

...Northeast...
A dynamic coastal system takes earlier in the week along/near the
New England Coast per model guidance. Strong upper level jet
energy upstream diving toward the trough base will amplify the
upper trough -- to the tune of 2+ standard deviations below late
July means at 500 mb-- which enhances the downstream QG forcing as
it encounters deep moisture at low- to mid-levels being drawn in
from the Atlantic Gulf stream, with a swath of ~1.75" PWs. As
previously noted...given the persistence of favorable cool season
dynamics with warm season thermodynamics (high deep- layer
TPW/theta-e values), have maintained the Slight Risk area pretty
much unchanged across parts of the Northeast, which fits the most
recent global guidance rather well.

Operational guidance shows 2-4 inches of rainfall across the
Slight Risk area from Wednesday into late Wednesday night/early
Thursday morning. Frontogenesis of the comma head could on its own
lead to efficient heavy rainfall; not much MU/ML CAPE will be
necessary to lead to flash flooding concerns.

...Four Corners States into the Central/Northern Plains...
Monsoonal flow, likely to be enhanced by Genevieve moving offshore
Baja California, brings elevated moisture over the Desert
Southwest through the central Rockies and into the central and
northern Plains. The more suppressed ridge will allow multiple mesoscale/convectively aided shortwaves to push over the top/across
the Rockies into the Plains. The Marginal Risk area here only
needed some cosmetic changes to better fit the most recent QPF
guidance but the differences did not reflect a change in the
forecast reasoning.

...Central Gulf Coast Region into parts of the Southeast...
Numerical guidance continued to show heavy...to potentially excessive...rainfall being forced/focused by a cold front
associated with the cyclone impacting New England. Still little
reason to question whether the moisture will be ample at the same
time that the effective bulk shear is sufficient for convective
organization. The inherited Marginal Risk areas for Wednesday into
Thursday night saw only a few cosmetic changes to better fit the
most recent QPF guidance.

Bann/Roth

Day 4 and Day 5

Valid 12Z Thu Jul 30 2026 - 12Z Sat Aug 01 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE LOWER MISSOURI AND MID TO UPPER MISSISSIPPI VALLEY...

...Lower Missouri Valley into the Mid-Upper Mississippi Valley...
On Day 4 (Thursday-Thursday night), convectively-aided shortwave
energy progressing east from the central-northern Plains will
amplify a bit (dig a bit farther south) upon reaching the Lower MO-
Mid MS Valleys) during this time as the ~600DM 500mb high becomes
centered farther west toward the Four Corners. There's near to
above average discrepancy amongst the 00Z global guidance. The GFS/
GEFS mean/AIGFS are a bit farther east compared to the ECMWF/ECENS
mean/EC AIFS, with the CMC camp basically in the middle in terms of
eastward progression. In addition, there remains latitudinal
differences with the heaviest QPF, with the 00Z UKMet the farthest
north. Given the MCS/upscale growth potential with this system,
considering the influx of 2-2.25+ PWs per the guidance,
concentrated areas of heavy rain are expected, especially across
the Corn Belt given the deep-layer moisture profile and high
surface dewpoints. Certainly an event that would warrant a Slight
Risk, which for now we've confined across eastern SD, far eastern
NE and northeast KS, into northwest MO, western 2/3 of Iowa, and
southern MN, where the global ensemble probabilities of >3" in
12/24 hours are highest.

On Day 5 (Friday-Friday night), have essentially shifted the
Slight Risk area farther downstream (east-southeast) per the global
guidance consensus. Globals all show spotty heavy 24hr rainfall
totals, i.e. 3-5+ inches, though again with some spatial spread in
the guidance. ECENS QPF exceedance probabilities have come up from
the previous run, and are certainly higher compared to the day 4
period (more expanded area of 3 to 5 inch probabilities).

...Four Corners States into the Central/Northern Plains...
Monsoonal flow and anomalous deep-layer moisture will maintain a
Marginal (isolated) excessive rainfall risk over eastern AZ and
much of MN (except SE portion) into southeast UT and through much
of CO. The expanding mid/upper level ridge (600dm heights at 500
mb) will likely limit the coverage compared to recent days,
especially by Friday.

...Central Gulf Coast Region into parts of the Southeast...
Heavy rainfall is expected along the New England cyclone's
trailing front near the FL/GA border. Moisture should be ample and
there could be enough effective bulk shear for convective
organization. The inherited Marginal Risk areas for Thursday into
Friday night saw only a few cosmetic changes to better fit the
most recent QPF guidance.

Hurley

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!_H2N8GRmbLXSfay9h6Ur7qMt06AFPP45QFDx-B1iO54d8ZyjHT0njbIADRtDqf8eKguLVyDXcZsHvmSVMO5NpjrSyOI$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!_H2N8GRmbLXSfay9h6Ur7qMt06AFPP45QFDx-B1iO54d8ZyjHT0njbIADRtDqf8eKguLVyDXcZsHvmSVMO5NY5p7fso$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!_H2N8GRmbLXSfay9h6Ur7qMt06AFPP45QFDx-B1iO54d8ZyjHT0njbIADRtDqf8eKguLVyDXcZsHvmSVMO5Nds-4vGk$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Mon Jul 27 19:55:24 2026

FOUS30 KWBC 271955
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
355 PM EDT Mon Jul 27 2026

Day 1
Valid 1832Z Mon Jul 27 2026 - 12Z Tue Jul 28 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL IN EFFECT FOR PARTS
OF SOUTHEAST WISCONSIN, NORTHEAST/EAST-CENTRAL ILLINOIS, AND NORTHWEST/WEST-CENTRAL INDIANA...

1830Z Special Update...
A SLGT Risk was added to parts of the Midwest from SE WI through
much of NE IL and NW IN, including the Chicago, Indianapolis, and
Milwaukee metro regions. This is due to ongoing heavy rainfall and
the expectation for intense rainfall rates to continue for several
hours while the threat slides southward with time. Both 17z runs
of the HRRR and RRFS support 2-5" additional rainfall amounts
through 06z, which would produce scattered areas of flash flooding.
Urban locations could see significant street flooding should
thunderstorms train over the region. As the complex pushes
southward this evening and overnight across central and southern
IL/IN, rainfall rates and the threat of backbuilding storms should
diminish as better forcing shifts eastward into the upper Ohio
Valley. See MPD 0861 for more information.

Snell

Previous Discussion...

...Four Corners States onto the Central Plains...
The monsoon ridge gets slightly suppressed south today by
shortwaves cresting its periphery over the Northern Rockies. This
will squelch the higher PW a bit south from previous days, but
otherwise the ridge remains in place with weak impulses rotating
around it to enhance ascent and resulting convection. Once again,
the focus for thunderstorm development will be across the higher
terrain late this morning, before expanding across the Four Corners
states, with some organization possible through 20-30 kts of bulk
shear. While PWs will still be +1 to +2 sigma from AZ through WY,
the most impressive CAPE (approaching 750 J/kg) look to be confined
to AZ/NM, which can be a better discriminator for excessive
rainfall potential within the monsoon. However, any convection has
the potential to produce intense rain rates leading to hourly
rainfall of 1-1.5", which could produce at least isolated flash
flood responses over vulnerable terrain features or burn scars.

Storms that develop across UT/WY/CO may feature faster forward
propagation (after brief slow downs during initiation) so the MRGL
risk was expanded slightly into the Central Plains. However, this
faster motion should at least somewhat limit the runoff potential.
Farther south into AZ a shortwave moving along the Mexico/Arizona
border within the elevated shear may help organized clusters of
storms moving more slowly westward, and this is reflected by
elevated (but still modest) probabilities for 3" of rain today.
Considered a targeted SLGT risk for the TWC CWA but simulated
reflectivity from the CAMs and the UA WRF were not sufficient for
an upgrade at this time.

...Great Lakes and Ohio Valley into the Northeast US...
A potent shortwave diving out of Ontario across the Great Lakes
will interact with a complex surface pattern over the region to
drive scattered to widespread thunderstorms through the day.
Activity this morning is already producing heavy rainfall rates
measured via MRMS of over 1"/hr within the pronounced ascent as it
impinges upon an impressive overlap of PW/CAPE measured via morning
12Z soundings at APX/GRB of near record values (1.7-2.1 PWs and
4000-5000 J/Kg CAPE). As the aftn progresses, convection will
become increasingly widespread as the shortwave dives south and
pushes a cold front (and accompanying wave of low pressure) through
the Great Lakes and southeast towards the Ohio Valley/Central
Appalachians). While the thermodynamic environment will support
intense rain rates within any thunderstorms today, and 40-50kts of
bulk shear will help organize storms into clusters and/or
supercells, mean winds of 30-40 kts suggest convection will remain
progressive, and Corfidi vectors do not support much
backbuilding/training. So while local impacts due to flash flooding
are possible, the overall risk matches best the MRGL risk category
so the inherited was changed only cosmetically for new guidance.

...Western Florida Peninsula...
Weak shortwave diving along or just west of the Florida Peninsula
will work together with broad directional jet- level diffluence to
spawn repeated rounds of thunderstorm activity today. This
convection will occur within robust PW anomalies reaching +1.5 to
+2.0 sigma for the southern half of Florida, which when combined
with SBCAPE exceeding 3000 J/kg will support torrential rain rates.
While shear will be minimal indicating pulse-type convection, weak
flow and resulting cell collisions or outflow mergers, as well as
the Gulf breeze, will support scattered to widespread
thunderstorms, all of which may contain 2-3"/hr rainfall. Due to
the nature of this convection, placing the axis of heaviest amounts
remains uncertain, but there is a common signal in both REFS and
HREF probabilities for locally more than 5" (20-40% chance) near
Tampa Bay, so the inherited MRGL risk was continued for this area,
but expanded along the coast for potential beneath the forcing
created by the upper diffluence, and added the Florida Keys after
coordination with WFO KEY.

...Coastal Mid-Atlantic...
A surface trough will sharpen east of I-95 this aftn providing a
focus for ascent and convective development. The high-res CAMs
suggest development will generally be isolated, but within
favorable thermodynamics characterized by PWs above 1.5 inches and
SBCAPE of 2000 J/kg or more. This will support intense rain rates
within any storms that develop, and both the REFS and HREF
neighborhood probabilities reach 50-70% for hourly rainfall of 1
inch or more. While there is some uncertainty into the coverage and
placement of activity this aftn, the inherited MRGL risk was
continued with just subtle cosmetic modifications since soils are
saturated from heavy antecedent rainfall.

Weiss

Day 2
Valid 12Z Tue Jul 28 2026 - 12Z Wed Jul 29 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR THE TRI-STATE
AREA OF NEW JERSEY, NEW YORK, AND CONNECTICUT...

...Southern Appalachians through New England...
An anomalously strong upper low will produce impressive dynamics to
create the potential for significant flash flooding across the
Tri-State area on Tuesday.

A shortwave moving across the Great Lakes today will deepen into a
closed low over Upstate NY Tuesday evening, and then amplify as it
curls southeast into New England. NAEFS 500-850mb heights fall to
below the 1st percentile (or even below the minimum climatology)
according to NAEFS by 00Z Wednesday. This intense system will help
drive increasing divergence downstream, which when combined with
the accompanying height falls will result in broad deep layer
ascent from the Mid-Atlantic into New England. At the same time,
the deepening system will force acceleration of the 850mb inflow,
reflected by NAEFS percentiles in the 850mb wind to above the 99th
percentile, forcing robust moisture convergence into the Mid-
Atlantic and Northeast.

As is typical for late July, PWs and SBCAPE will be near
climatological maximums (reflected via the SPC sounding
climatology), and this event will be no different as PWs are
progged to be around 1.75 inches overlapping MUCAPE of 2000-3000
J/kg. Strong ascent in the vicinity of this anomalous closed low
and near the accompanying occluded surface low into these strong
thermodynamics sets a situation favorable for heavy, training
rainfall, and flash flooding.

Both HREF and REFS probabilities for 2"/hr rainfall reach 15-25%,
and Corfidi vectors aligned anti- parallel to the mean wind which
will be aligned to the approaching front, suggests a strong
backbuilding and training potential. While there is still quite a
bit of timing spread among the various CAMs as to when the
strongest convection will pivot through, the exceedance
probabilities for both 5"/24hrs and 8"/24hrs are impressive (40-70%
and 10-30%, respectively) despite some uncertainty in position.
This combined with the 100-yr RI exceedances exceeding 20% indicate
increasing confidence for widespread flash flooding with locally
significant events possible. After coordination with the affected
WFOs, a MDT risk has been introduced, focused in the Tri-State
region where FFG is already more vulnerable due to recent rain and
the general urban corridor.

Despite the MDT risk in place for the Tri-State area, it should be
noted that the REFS probabilities are a bit displaced south from
the HREF, and focus the heaviest rainfall closer to Philadelphia.
The surrounding SLGT risk has been expanded to account for this
potential, and there is potential for additional adjustments to the
higher-end risk areas in place for Tuesday/Tuesday night.

...Four Corners States across the Central Plains...
The expansive monsoon ridge will become additionally squeezed Tuesday
as shortwaves rotate anti-cyclonically around it both to the north
and south. This will again support at least scattered monsoon
convection as PWs above 1 inch rise northward into the Four Corners
overlapped with sufficient instability for afternoon development.
Once again the risk will likely initiate in the higher terrain
during the onset of peak heating, and then there appears to be
sufficient shear (20-30 kts) for some organization off the terrain
and into the lower elevations, primarily in NM and CO.

Storm motions will again be weak as reflected by 0-6km mean winds
of just 5-10 kts, and locally chaotic motion is likely where
storm clusters interact with other boundaries or
mergers/collisions. The CAMs, as well as HREF/REFS PMM suggest a
local enhancement to QPF from far southeast Arizona through western
New Mexico and into eastern Colorado, which is where multiple
rounds of storms are more likely. After coordination with the
affected WFOs, a SLGT risk was introduced for this axis where a
greater risk for flash flooding exists, especially across
vulnerable terrain features.

...Western Florida Peninsula and the Keys...
A shortwave diving along the Florida Peninsula/Western Gulf will
interact with broad diffluence aloft to maintain deep layer ascent
for convection across the eastern Gulf and into parts of South
Florida and the keys. Mean 0-6km winds of just 5-10 kts will be
aligned SW to NW, anti- parallel to collapsed Corfidi vectors, and
parallel to the Keys. This suggests that convection will repeatedly
build across the Gulf where PWs will be pooled at 2-2.25 inches
within impressive 2000-3000 J/kg MUCAPE. This will support
widespread activity which is reflected by high-res CAM simulated
reflectivity. Within these impressive thermodynamics, rainfall
rates of 2-3"/hr are likely at times, leading to 2-4" of rainfall
with locally higher amounts. Some of these areas will be sensitive
from heavy rain on D1, so a MRGL risk was added for the potential
for isolated impacts on Tuesday.

...Missouri Valley...
A weakening but notable shortwave and accompanying vorticity
impulse will crest the monsoon ridge to the rest and then race
steadily southeast over the Central Plains and into the Missouri
Valley by Tuesday night. This feature will help push a cold front
southward towards the Ozarks, but become aligned parallel to the
mid-level flow causing it to stall in a NW to SE oriented fashion.
As the shortwave moves along this front Tuesday night it will help
accelerate the already intensifying LLJ to draw robust
thermodynamics northward. This will support organizing clusters of
convection or an MCS aligning to the front as both 0-6km mean winds
and Corfidi vectors become parallel. With rainfall rates likely
reaching 1-2"/hr at times, any training has the potential to
produce 2-4" of rain (HREF and REFS probabilities for 3+" 20-25%)
leading to instances of flash flooding.

Weiss

Day 3
Valid 12Z Wed Jul 29 2026 - 12Z Thu Jul 30 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE NORTHEAST...

...Northeast...
An occluding surface low beneath an anomalous mid-level closed low
will bring heavy rainfall to parts of the Northeast and New England
on Wednesday. Strong mid-level divergence combined with upper
diffluence will produce deep layer ascent into robust
thermodynamics characterized by a plume of 1.5 to 1.7 inch PWs and
MUCAPE of 500-750 J/kg. At the same time, the deepening system will
accelerate the 850mb inflow to 30-40 kts, tapping Atlantic/Gulf
Stream moisture to further enhance the potential for heavy rain.

This will support an expansive area of heavy rainfall for the
Northeast, with rainfall rates of 1"/hr or more possible at times,
leading to widespread 1-3" of rain with locally higher amounts
(SREF, GEFS, and ECENS all have around a 10% chance for 3+" of
rain).

There will be a sharp gradient of instability which may
limit the rates into VT/NH/ME, and FFG is elevated farther north
due to recent dryness. For this reason, and after coordination with
the WFOs, the SLGT risk was modified to encompass primarily
southern New England, with a broader MRGL risk covering most of the
Northeast.

...Four Corners States into the Central/Northern Plains...
Monsoonal flow, likely to be enhanced by Genevieve moving offshore
Baja California, brings elevated moisture over the Desert
Southwest through the central Rockies and into the central and
northern Plains. The more suppressed ridge will allow multiple mesoscale/convectively aided shortwaves to push over the top/across
the Rockies into the Plains. It is possible that some of these
could result in locally heavier rain across the High Plains of CO,
and this could fall atop soils saturated from heavy rain on D2. At
this time confidence is not high enough for an upgrade risk due
to low probabilities and uncertainty about storm coverage/speed,
but it is possible a SLGT risk may be needed for parts of the High
Plains with later updates.

...Central Gulf Coast Region into parts of the Southeast...
A cold front stalling along the Gulf Coast will be a focus for slow
moving and training thunderstorms on Wednesday. Guidance continues
to indicate a low-probability threat for at least 3" of rain due to
training of 1-2"/hr rain rates within favorable thermodynamics.
This region can generally tolerate significant rain rates and this
amount of rainfall, but any more pronounced training could result
in isolated flash flood related impacts.

Weiss

Day 4 and Day 5

Valid 12Z Thu Jul 30 2026 - 12Z Sat Aug 01 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE LOWER MISSOURI AND MID TO UPPER MISSISSIPPI VALLEY...

20Z Update...
Forecast remains largely unchanged. Only adjustments
to the Day 4/5 EROs was to extend the SLGT risks a tad farther
south given latest model QPF and the tendency for thundertsorms in north-northwesterly flow to extend and potentially backbuild
farther south than initially modeled.

Snell

Previous Discussion...

...Lower Missouri Valley into the Mid-Upper Mississippi Valley...
On Day 4 (Thursday-Thursday night), convectively-aided shortwave
energy progressing east from the central-northern Plains will
amplify a bit (dig a bit farther south) upon reaching the Lower MO-
Mid MS Valleys) during this time as the ~600DM 500mb high becomes
centered farther west toward the Four Corners. There's near to
above average discrepancy amongst the 12Z global guidance. The
GFS/ GEFS mean/AIGFS are a bit farther east compared to the
ECMWF/ECENS mean/EC AIFS, with the CMC camp basically in the middle
in terms of eastward progression. In addition, there remains
latitudinal differences with the heaviest QPF, with the 00Z UKMet
the farthest north. Given the MCS/upscale growth potential with
this system, considering the influx of 2-2.25+ PWs per the
guidance, concentrated areas of heavy rain are expected, especially
across the Corn Belt given the deep-layer moisture profile and
high surface dewpoints. Certainly an event that would warrant a
Slight Risk, which for now we've confined across eastern SD, far
eastern NE and northeast KS, into northwest MO, western 2/3 of
Iowa, and southern MN, where the global ensemble probabilities of

3" in 12/24 hours are highest.

On Day 5 (Friday-Friday night), have essentially shifted the
Slight Risk area farther downstream (east-southeast) per the global
guidance consensus. Globals all show spotty heavy 24hr rainfall
totals, i.e. 3-5+ inches, though again with some spatial spread in
the guidance. ECENS QPF exceedance probabilities have come up from
the previous run, and are certainly higher compared to the day 4
period (more expanded area of 3 to 5 inch probabilities).

...Four Corners States into the Central/Northern Plains...
Monsoonal flow and anomalous deep-layer moisture will maintain a
Marginal (isolated) excessive rainfall risk over eastern AZ and
much of MN (except SE portion) into southeast UT and through much
of CO. The expanding mid/upper level ridge (600dm heights at 500
mb) will likely limit the coverage compared to recent days,
especially by Friday.

...Central Gulf Coast Region into parts of the Southeast...
Heavy rainfall is expected along the New England cyclone's
trailing front near the FL/GA border. Moisture should be ample and
there could be enough effective bulk shear for convective
organization. The inherited Marginal Risk areas for Thursday into
Friday night saw only a few cosmetic changes to better fit the
most recent QPF guidance.

Hurley

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!95xJ1_EIiFE2kQxsoYqKINifJkqjB0UtTjGU0f4-Sf4suHd4s2KUZheQd7x5HyKeBprZ6qD2v05l2kJXsH85urDJYMg$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!95xJ1_EIiFE2kQxsoYqKINifJkqjB0UtTjGU0f4-Sf4suHd4s2KUZheQd7x5HyKeBprZ6qD2v05l2kJXsH857uGogJA$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!95xJ1_EIiFE2kQxsoYqKINifJkqjB0UtTjGU0f4-Sf4suHd4s2KUZheQd7x5HyKeBprZ6qD2v05l2kJXsH85ge_uYsg$

$$

= = =
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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Jul 28 00:50:32 2026

FOUS30 KWBC 280049
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
849 PM EDT Mon Jul 27 2026

Day 1
Valid 01Z Tue Jul 28 2026 - 12Z Tue Jul 28 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL IN EFFECT FOR PARTS
OF CENTRAL INDIANA AND ILLINOIS...

...Great Lakes and Ohio Valley...
Shortwave crossing the Upper Great Lakes tonight within a
northwesterly flow regime extending into the Ohio Valley and East
Coast will drive additional thunderstorm and heavy rain chances. Of
most concern is an area of west-northwest flanking storms that
continue to exhibit training/back-building potential in parts of
central and southern IL/IN this evening. High levels of MLCAPE
(4000-5000 J/kg) continue to be estimated in the inflow sector
across southern IA, IL and into southern IN, which will help storms
maintain themselves after sunset. 23Z experimental WoFS depicts
40-70% chnaces for additional rainfall amounts above 2 inches
within the SLGT risk area and along the IL-IN border. However, the
mid- level flow does begin to become less favorable for back-
building after about 03Z and better forcing quickly shifts eastward
due to the deepening trough over the Northeast. Thus, the
scattered flash flood threat over IL/IN remains, but is short-
lived.

For the remainder of the Great Lakes and Ohio Valley region, the
left-exit region of a potent jet streak rounding the northwest
periphery of the anchored upper ridge over the southern High Plains
will spawn overnight thunderstorm development. Most storms should
be progressive within the fast northwest flow, but brief periods of
training may lead to a localized flash flood threat. The greatest
potential for this appears to be over the eastern L.P. of MI and
possibly the Upper Ohio Valley into far western NY State depending
on upstream development. CAMs have been fairly unreliable today,
but the latest 23Z HRRR seems to capture current radar
representation well and has a realistic outlook for tonight.

...Northeast...
Slow-moving isolated thunderstorms with impressive rainfall rates
continue across the Northeast along I-95 from Baltimore to the
Lower Hudson Valley, but should decrease in coverage this evening
following sunset. Otherwise, increasing mid-level southwesterly
flow and PWs over 1.5" will lead to addition thunderstorm chances
across parts of central PA. A few inches of rainfall could lead to
localized flooding concerns.

...Four Corners States into the Central Plains...
The vast south-central U.S. ridge remains in place with weak
impulses rotating around it to enhance ascent and resulting
convection. Thunderstorms are ongoing on the western and northern
periphery of this ridge from southeast AZ and NM to NE/KS. Most
storms are scattered in nature and not organized enough for a risk
level above MRGL. However, any convection has the potential to
produce intense rain rates leading to hourly rainfall of 1-1.5",
which can still produce at least isolated flash flood responses
over vulnerable terrain features or burn scars.

Over the Central Plain, ongoing convection will eventually try to
congeal along an area of low-to-mid level convergence along the
NE/KS border, but should remain progressive enough within westerly
flow to limit flash flooding. Maintained the MRGL risk here and
preferred the 23Z HRRR vs the 20Z RRFS solution.

Snell

Day 2
Valid 12Z Tue Jul 28 2026 - 12Z Wed Jul 29 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR THE TRI-STATE
AREA OF NEW JERSEY, NEW YORK, AND CONNECTICUT...

...Southern Appalachians through New England...
An anomalously strong upper low will produce impressive dynamics to
create the potential for significant flash flooding across the
Tri-State area on Tuesday.

A shortwave moving across the Great Lakes today will deepen into a
closed low over Upstate NY Tuesday evening, and then amplify as it
curls southeast into New England. NAEFS 500-850mb heights fall to
below the 1st percentile (or even below the minimum climatology)
according to NAEFS by 00Z Wednesday. This intense system will help
drive increasing divergence downstream, which when combined with
the accompanying height falls will result in broad deep layer
ascent from the Mid-Atlantic into New England. At the same time,
the deepening system will force acceleration of the 850mb inflow,
reflected by NAEFS percentiles in the 850mb wind to above the 99th
percentile, forcing robust moisture convergence into the Mid-
Atlantic and Northeast.

As is typical for late July, PWs and SBCAPE will be near
climatological maximums (reflected via the SPC sounding
climatology), and this event will be no different as PWs are
progged to be around 1.75 inches overlapping MUCAPE of 2000-3000
J/kg. Strong ascent in the vicinity of this anomalous closed low
and near the accompanying occluded surface low into these strong
thermodynamics sets a situation favorable for heavy, training
rainfall, and flash flooding.

Both HREF and REFS probabilities for 2"/hr rainfall reach 15-25%,
and Corfidi vectors aligned anti- parallel to the mean wind which
will be aligned to the approaching front, suggests a strong
backbuilding and training potential. While there is still quite a
bit of timing spread among the various CAMs as to when the
strongest convection will pivot through, the exceedance
probabilities for both 5"/24hrs and 8"/24hrs are impressive (40-70%
and 10-30%, respectively) despite some uncertainty in position.
This combined with the 100-yr RI exceedances exceeding 20% indicate
increasing confidence for widespread flash flooding with locally
significant events possible. After coordination with the affected
WFOs, a MDT risk has been introduced, focused in the Tri-State
region where FFG is already more vulnerable due to recent rain and
the general urban corridor.

Despite the MDT risk in place for the Tri-State area, it should be
noted that the REFS probabilities are a bit displaced south from
the HREF, and focus the heaviest rainfall closer to Philadelphia.
The surrounding SLGT risk has been expanded to account for this
potential, and there is potential for additional adjustments to the
higher-end risk areas in place for Tuesday/Tuesday night.

...Four Corners States across the Central Plains...
The expansive monsoon ridge will become additionally squeezed Tuesday
as shortwaves rotate anti-cyclonically around it both to the north
and south. This will again support at least scattered monsoon
convection as PWs above 1 inch rise northward into the Four Corners
overlapped with sufficient instability for afternoon development.
Once again the risk will likely initiate in the higher terrain
during the onset of peak heating, and then there appears to be
sufficient shear (20-30 kts) for some organization off the terrain
and into the lower elevations, primarily in NM and CO.

Storm motions will again be weak as reflected by 0-6km mean winds
of just 5-10 kts, and locally chaotic motion is likely where
storm clusters interact with other boundaries or
mergers/collisions. The CAMs, as well as HREF/REFS PMM suggest a
local enhancement to QPF from far southeast Arizona through western
New Mexico and into eastern Colorado, which is where multiple
rounds of storms are more likely. After coordination with the
affected WFOs, a SLGT risk was introduced for this axis where a
greater risk for flash flooding exists, especially across
vulnerable terrain features.

...Western Florida Peninsula and the Keys...
A shortwave diving along the Florida Peninsula/Western Gulf will
interact with broad diffluence aloft to maintain deep layer ascent
for convection across the eastern Gulf and into parts of South
Florida and the keys. Mean 0-6km winds of just 5-10 kts will be
aligned SW to NW, anti- parallel to collapsed Corfidi vectors, and
parallel to the Keys. This suggests that convection will repeatedly
build across the Gulf where PWs will be pooled at 2-2.25 inches
within impressive 2000-3000 J/kg MUCAPE. This will support
widespread activity which is reflected by high-res CAM simulated
reflectivity. Within these impressive thermodynamics, rainfall
rates of 2-3"/hr are likely at times, leading to 2-4" of rainfall
with locally higher amounts. Some of these areas will be sensitive
from heavy rain on D1, so a MRGL risk was added for the potential
for isolated impacts on Tuesday.

...Missouri Valley...
A weakening but notable shortwave and accompanying vorticity
impulse will crest the monsoon ridge to the rest and then race
steadily southeast over the Central Plains and into the Missouri
Valley by Tuesday night. This feature will help push a cold front
southward towards the Ozarks, but become aligned parallel to the
mid-level flow causing it to stall in a NW to SE oriented fashion.
As the shortwave moves along this front Tuesday night it will help
accelerate the already intensifying LLJ to draw robust
thermodynamics northward. This will support organizing clusters of
convection or an MCS aligning to the front as both 0-6km mean winds
and Corfidi vectors become parallel. With rainfall rates likely
reaching 1-2"/hr at times, any training has the potential to
produce 2-4" of rain (HREF and REFS probabilities for 3+" 20-25%)
leading to instances of flash flooding.

Weiss

Day 3
Valid 12Z Wed Jul 29 2026 - 12Z Thu Jul 30 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE NORTHEAST...

...Northeast...
An occluding surface low beneath an anomalous mid-level closed low
will bring heavy rainfall to parts of the Northeast and New England
on Wednesday. Strong mid-level divergence combined with upper
diffluence will produce deep layer ascent into robust
thermodynamics characterized by a plume of 1.5 to 1.7 inch PWs and
MUCAPE of 500-750 J/kg. At the same time, the deepening system will
accelerate the 850mb inflow to 30-40 kts, tapping Atlantic/Gulf
Stream moisture to further enhance the potential for heavy rain.

This will support an expansive area of heavy rainfall for the
Northeast, with rainfall rates of 1"/hr or more possible at times,
leading to widespread 1-3" of rain with locally higher amounts
(SREF, GEFS, and ECENS all have around a 10% chance for 3+" of
rain).

There will be a sharp gradient of instability which may
limit the rates into VT/NH/ME, and FFG is elevated farther north
due to recent dryness. For this reason, and after coordination with
the WFOs, the SLGT risk was modified to encompass primarily
southern New England, with a broader MRGL risk covering most of the
Northeast.

...Four Corners States into the Central/Northern Plains...
Monsoonal flow, likely to be enhanced by Genevieve moving offshore
Baja California, brings elevated moisture over the Desert
Southwest through the central Rockies and into the central and
northern Plains. The more suppressed ridge will allow multiple mesoscale/convectively aided shortwaves to push over the top/across
the Rockies into the Plains. It is possible that some of these
could result in locally heavier rain across the High Plains of CO,
and this could fall atop soils saturated from heavy rain on D2. At
this time confidence is not high enough for an upgrade risk due
to low probabilities and uncertainty about storm coverage/speed,
but it is possible a SLGT risk may be needed for parts of the High
Plains with later updates.

...Central Gulf Coast Region into parts of the Southeast...
A cold front stalling along the Gulf Coast will be a focus for slow
moving and training thunderstorms on Wednesday. Guidance continues
to indicate a low-probability threat for at least 3" of rain due to
training of 1-2"/hr rain rates within favorable thermodynamics.
This region can generally tolerate significant rain rates and this
amount of rainfall, but any more pronounced training could result
in isolated flash flood related impacts.

Weiss

Day 4 and Day 5

Valid 12Z Thu Jul 30 2026 - 12Z Sat Aug 01 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE LOWER MISSOURI AND MID TO UPPER MISSISSIPPI VALLEY...

20Z Update...
Forecast remains largely unchanged. Only adjustments
to the Day 4/5 EROs was to extend the SLGT risks a tad farther
south given latest model QPF and the tendency for thundertsorms in north-northwesterly flow to extend and potentially backbuild
farther south than initially modeled.

Snell

Previous Discussion...

...Lower Missouri Valley into the Mid-Upper Mississippi Valley...
On Day 4 (Thursday-Thursday night), convectively-aided shortwave
energy progressing east from the central-northern Plains will
amplify a bit (dig a bit farther south) upon reaching the Lower MO-
Mid MS Valleys) during this time as the ~600DM 500mb high becomes
centered farther west toward the Four Corners. There's near to
above average discrepancy amongst the 12Z global guidance. The
GFS/ GEFS mean/AIGFS are a bit farther east compared to the
ECMWF/ECENS mean/EC AIFS, with the CMC camp basically in the middle
in terms of eastward progression. In addition, there remains
latitudinal differences with the heaviest QPF, with the 00Z UKMet
the farthest north. Given the MCS/upscale growth potential with
this system, considering the influx of 2-2.25+ PWs per the
guidance, concentrated areas of heavy rain are expected, especially
across the Corn Belt given the deep-layer moisture profile and
high surface dewpoints. Certainly an event that would warrant a
Slight Risk, which for now we've confined across eastern SD, far
eastern NE and northeast KS, into northwest MO, western 2/3 of
Iowa, and southern MN, where the global ensemble probabilities of

3" in 12/24 hours are highest.

On Day 5 (Friday-Friday night), have essentially shifted the
Slight Risk area farther downstream (east-southeast) per the global
guidance consensus. Globals all show spotty heavy 24hr rainfall
totals, i.e. 3-5+ inches, though again with some spatial spread in
the guidance. ECENS QPF exceedance probabilities have come up from
the previous run, and are certainly higher compared to the day 4
period (more expanded area of 3 to 5 inch probabilities).

...Four Corners States into the Central/Northern Plains...
Monsoonal flow and anomalous deep-layer moisture will maintain a
Marginal (isolated) excessive rainfall risk over eastern AZ and
much of MN (except SE portion) into southeast UT and through much
of CO. The expanding mid/upper level ridge (600dm heights at 500
mb) will likely limit the coverage compared to recent days,
especially by Friday.

...Central Gulf Coast Region into parts of the Southeast...
Heavy rainfall is expected along the New England cyclone's
trailing front near the FL/GA border. Moisture should be ample and
there could be enough effective bulk shear for convective
organization. The inherited Marginal Risk areas for Thursday into
Friday night saw only a few cosmetic changes to better fit the
most recent QPF guidance.

Hurley

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!7tLaq7TkE7lbHtGcPA5rkdYwzQ4pqIFL6iE0_OzvIEKRH2f2fT5b0FeybfiL_yykzsnYRNobqAH0bAHB78_EU8uJwe8$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!7tLaq7TkE7lbHtGcPA5rkdYwzQ4pqIFL6iE0_OzvIEKRH2f2fT5b0FeybfiL_yykzsnYRNobqAH0bAHB78_ErMK0_wY$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!7tLaq7TkE7lbHtGcPA5rkdYwzQ4pqIFL6iE0_OzvIEKRH2f2fT5b0FeybfiL_yykzsnYRNobqAH0bAHB78_ERmKiz5I$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Jul 28 08:23:58 2026

FOUS30 KWBC 280823
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
423 AM EDT Tue Jul 28 2026

Day 1
Valid 12Z Tue Jul 28 2026 - 12Z Wed Jul 29 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR THE TRI-
STATE AREA OF NEW JERSEY, NEW YORK, AND Connecticut...

...Southern Appalachians through New England...
An anomalously strong upper low will produce impressive dynamics to
create the potential for significant flash flooding across the
Tri-State area today and tonight.

A closed low will be forming over Upstate NY this evening and then
continue to amplify and deepen as it curls southeast into New
England. This intense system will help drive increasing divergence
downstream, which when combined with the accompanying height falls
will result in broad deep layer ascent from the Mid- Atlantic into
New England. At the same time, the deepening system will force
acceleration of the 850mb inflow,

Precipitable water values and the magnitude of the surface-based
CAPE will be near climatological maximums (reflected via the SPC
sounding climatology), with precipitable water values around 1.75
inches overlapping most-unstable CAPE of 2000-3000 J/kg. Strong
ascent in the vicinity of this anomalous closed low and near the
accompanying occluded surface low into these strong thermodynamics
sets a situation favorable for heavy, training rainfall, and flash
flooding.

The 28/00Z HREF and REFS both maintain probabilities for 2"/hr
rainfall reach 15-25%, and Corfidi vectors aligned anti- parallel
to the mean wind which will be aligned to the approaching front,
which suggests a strong backbuilding and training potential. This
fostered enough confidence for the day-shift to upgrade part of the
area to a Moderate Risk. The Moderate risk was maintained with the
western boundary of the Slight and Moderate expanded a bit
westward--mainly in New York state--due to the model suite slowing
down the timing of convective initiation and propagation.

...Four Corners States across the Central Plains...
The expansive monsoon ridge will become additionally squeezed as
shortwaves rotate anti-cyclonically around it both to the north and
south. This will again support at least scattered monsoon
convection as precipitable water values at or above 1 inch northward
into the Four Corners overlapped with sufficient instability for
afternoon development. Once again the risk will likely initiate in
the higher terrain during the onset of peak heating, and then there
appears to be sufficient shear (20-30 kts) for some organization
off the terrain and into the lower elevations, primarily in New
Mexico and Colorado, although there is potential for storms to be
very slow movers.

...Western Florida Peninsula and the Keys...
A shortwave diving along the Florida Peninsula/Western Gulf will
interact with broad diffluence aloft to maintain deep layer ascent
for convection across the eastern Gulf and into parts of South
Florida and the keys. Mean 0-6km winds of just 5-10 kts will be
aligned SW to NW, anti- parallel to collapsed Corfidi vectors, and
parallel to the Keys. This suggests that convection will repeatedly
build across the Gulf where PWs will be pooled at 2-2.25 inches
within impressive 2000-3000 J/kg MUCAPE leading to 2-4" of
rainfall with locally higher amounts.

...Missouri Valley...
Overnight convection leading into the start of the Day 1 period at
29/12Z prompted a Slight Risk area ahead of the storms. The
expectation is that the storms will weaken...followed by the next
round of storms later today into tonight as a weakening shortwave
crests the monsoon ridge before diving southeast. As the shortwave
moves along a front tonight...it will help accelerate the already
intensifying LLJ to draw robust thermodynamics northward. This will
support organizing clusters of convection or an MCS aligning to
the front as both 0-6km mean winds and Corfidi vectors become
parallel. With rainfall rates likely reaching 1-2"/hr at times, any
training has the potential to produce 2-4" of rain (HREF and REFS
probabilities for 3+" 20-25%) leading to instances of flash
flooding.

Bann/Weiss

Day 2
Valid 12Z Wed Jul 29 2026 - 12Z Thu Jul 30 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE NORTHEAST...

...Northeast...
Rainfall rates and additional rainfall amounts will initially be
heavy early in the period over the eastern portion of the Northeast
before they begin to diminish on Wednesday as an anomalously deep
low pressure system begins to occlude. There should be rainfall
rates around one inch per hour leading to widespread 1-3" of rain
with locally higher amounts.

The latest guidance still depicts a sharp gradient of instability
which may limit the rates in parts of Vermont, New Hampshire and
Maine. This part of the Northeast US should have received less
rainfall with Flash Flood Guidance less likely to have been
compromised. The previous outlook largely had this covered and
changes were fairly minor with this outlook.

...Four Corners States into the Central/Northern Plains...
Monsoonal flow persists with isolated to widely scattered
convection extending from the Four Corners region north and
eastward...perhaps extending as far east as the plains of Colorado.
Some of this rain could fall atop soils saturated from heavy rain
on Tuesday and Tuesday night. It remains possible that a Slight
Risk area may be needed for parts of the High Plains but there was
not enough confidence to do so in this outlook.

...Central Gulf Coast Region into parts of the Southeast...
A cold front stalling along the Gulf Coast will be a focus for slow
moving and training thunderstorms on Wednesday. Guidance continues
to indicate a low-probability threat for at least 3" of rain due to
training of 1-2"/hr rain rates within favorable thermodynamics.
This region can generally tolerate significant rain rates and this
amount of rainfall, but any more pronounced training could result
in isolated flash flood related impacts.

Bann/Weiss

Day 3
Valid 12Z Thu Jul 30 2026 - 12Z Fri Jul 31 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE LOWER MISSOURI AND MID TO UPPER MISSISSIPPI VALLEY...

...Lower Missouri Valley into the Mid-Upper Mississippi Valley...
Shortwave energy will be progressing east southeast as it tracks
across parts of the central and northern plains on Thursday into
Thursday night/early Friday morning. The shortwave energy will be
encountering an increasingly moist and unstable airmass with
precipitable water values in excess of 2 inches being drawn into
the region ahead of the shortwave. Given the MCS/upscale growth
potential with this system, concentrated areas of heavy rain are
expected, especially across the Corn Belt. The Slight risk area
already issued for Thursday still covers the risk....especially
where the global ensemble probabilities of >3" in 12/24 hours are
highest.

...Four Corners States into the Central/Northern Plains...
Monsoonal flow and anomalous deep-layer moisture will maintain an
isolated excessive rainfall risk extending from eastern Arizona
northeastward across much of western and northern New Mexico into
parts of Colorado. The expanding mid/upper level ridge will likely
limit the coverage compared to recent days.

...Central Gulf Coast Region into parts of the Southeast...
Heavy rainfall is expected along a front associated with a low
pressure system which will be pulling away from New England.
Heavy rainfall with some potential of flooding will be focused
along and near the front...especially over parts of Florida and
Georgia line.

Bann

Day 4 and Day 5

Valid 12Z Fri Jul 31 2026 - 12Z Sun Aug 02 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FRIDAY ACROSS
PARTS OF THE MID AND UPPER MISSISSIPPI, AND ON SATURDAY OVER
PORTIONS OF THE LOWER OHIO VALLEY, TENNESSEE VALLEY, AND DEEP
SOUTH...

...Mississippi Valley-Ohio Valley-Tennessee Valley-Deep South...
On Day 4 (Friday-Friday night), minor changes were made to
yesterday's Day 5 ERO, including refinements to the Slight Risk
area over parts of the Mid-Upper MS Valley, based on the latest
(00Z) global deterministic and probabilistic QPFs. The operational
models continue to show max 24hr totals in the 3-5" range,
particularly over IA-southeast MN-southwest WI, though again with
some spatial spread in the guidance. 00Z Operational ECMWF has a
bit more areal coverage of the 3+ inch totals, while the ECENS QPF
exceedance probabilities have once again come up from the previous
run. Based on the latest guidance, along with the most recent ECMWF
EFI output (EFI values aoa 0.6), have nudged the southern portion
of the Slight Risk area a little farther north across the Mid MS
Valley.

On Day 5 (Saturday-Saturday night), the globals continue to show a
fairly vigorous 500 mb trough/embedded shortwave energy slowly pivoting
into the Mid MS Valley. There isn't as strong of a signal in the
QPF guidance compared to the previous couple of days; however, the
amplifying upper level trough (favorable Qs forcing and increasing
effective bulk shear) will combine with a favorable thermodynamic
profile (ML CAPEs 1000-2000 J/Kg along a swath of 1.8-2.1" PWs) to
generate organized heavy rainfall threat across western portions
of the Lower OH Valley into the TN Valley and perhaps as far south
as southern AL, depending on how far south the upper shortwave and
favorable 0-6KM bulk shear can get. Concern within this area will
be heavy rainfall rates (2+ in/hr) given the thermodynamic profile,
along with the potential for cell training of convection as the
upper shortwave begins to stall and the low-level inflow out ahead
of it increases up and aligns more parallel to the mean 850-300 mb
flow. Because of these factors, we felt that a Slight Risk was
warranted.

...Four Corners States into the Southern-Central High Plains...
Monsoonal flow and anomalous deep-layer moisture will maintain a
Marginal (isolated) excessive rainfall risk over eastern AZ and
much of NM into much of CO. The expanding mid/upper level ridge
(600dm heights at 500 mb) will likely limit the coverage compared
to recent days, especially on Friday.

...Central Gulf Coast Region into parts of the Southeast...
Heavy rainfall is expected along the New England cyclone's trailing
front near the FL/GA border, the front that will become more
quasi-stationary Thu-Fri before lifting lifting back north on Sat
ahead of the approaching upper trough. Deep-layer moisture and
instability should be more than sufficient and the guidance shows
sufficient effective bulk shear (0-6km magnitudes generally over 20
kts) for more organized/persistent convective organization. As a
result, have maintained the inherited Marginal Risk on Day 4 (Fri-
Fri night), with a similar Marginal Risk area on Day 5 (Sat-Sat
night).

Hurley

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!625rGPKX3BNVMkV19WxQ735LR6zgZBy2PBk8I4na8-uB1OKFztBmBMWu5VLcvh1_qqmj35KSuZPSnS2ds0QpAHiObZE$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!625rGPKX3BNVMkV19WxQ735LR6zgZBy2PBk8I4na8-uB1OKFztBmBMWu5VLcvh1_qqmj35KSuZPSnS2ds0QpDK6ld94$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!625rGPKX3BNVMkV19WxQ735LR6zgZBy2PBk8I4na8-uB1OKFztBmBMWu5VLcvh1_qqmj35KSuZPSnS2ds0QpHX0l0y4$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Jul 28 13:52:46 2026

FOUS30 KWBC 281352
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
952 AM EDT Tue Jul 28 2026

Day 1
Valid 1345Z Tue Jul 28 2026 - 12Z Wed Jul 29 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR PARTS OF
EASTERN PENNSYLVANIA, NEW JERSEY, SOUTHERN NEW YORK, AND FAR
WESTERN CONNECTICUT...

...Southern Appalachians through New England...
1345Z SPECIAL UPDATE: A special update was coordinated with WFO Mt.
Holly and the National Water Center to extend the Moderate Risk
southward through the remainder of eastern Pennsylvania, as well as
the I-95 corridor through Philadelphia and Wilmington, DE.
Increasing hi-res model signal for intense rain rates, particularly
between 18Z and 03Z, prompted the upgrade. The combination of
moderate to strong instability and PW values increasing through the
day to between 1.6 and 1.9 inches will make rain rates reaching 2
inches per hour in the strongest convection likely, and there is a
chance the most organized clusters could see rain rates reach 3
inches per hour. In an area with a lot of flashy streams and
urbanization, this will make flash flooding increasingly likely
this afternoon, potentially impacting the evening rush in parts of
the area.

PREVIOUS DISCUSSION: An anomalously strong upper low will produce
impressive dynamics to create the potential for significant flash
flooding across the Tri-State area today and tonight.

A closed low will be forming over Upstate NY this evening and then
continue to amplify and deepen as it curls southeast into New
England. This intense system will help drive increasing divergence
downstream, which when combined with the accompanying height falls
will result in broad deep layer ascent from the Mid- Atlantic into
New England. At the same time, the deepening system will force
acceleration of the 850mb inflow,

Precipitable water values and the magnitude of the surface-based
CAPE will be near climatological maximums (reflected via the SPC
sounding climatology), with precipitable water values around 1.75
inches overlapping most-unstable CAPE of 2000-3000 J/kg. Strong
ascent in the vicinity of this anomalous closed low and near the
accompanying occluded surface low into these strong thermodynamics
sets a situation favorable for heavy, training rainfall, and flash
flooding.

The 28/00Z HREF and REFS both maintain probabilities for 2"/hr
rainfall reach 15-25%, and Corfidi vectors aligned anti- parallel
to the mean wind which will be aligned to the approaching front,
which suggests a strong backbuilding and training potential. This
fostered enough confidence for the day-shift to upgrade part of the
area to a Moderate Risk. The Moderate risk was maintained with the
western boundary of the Slight and Moderate expanded a bit
westward--mainly in New York state--due to the model suite slowing
down the timing of convective initiation and propagation.

...Four Corners States across the Central Plains...
The expansive monsoon ridge will become additionally squeezed as
shortwaves rotate anti-cyclonically around it both to the north and
south. This will again support at least scattered monsoon
convection as precipitable water values at or above 1 inch northward
into the Four Corners overlapped with sufficient instability for
afternoon development. Once again the risk will likely initiate in
the higher terrain during the onset of peak heating, and then there
appears to be sufficient shear (20-30 kts) for some organization
off the terrain and into the lower elevations, primarily in New
Mexico and Colorado, although there is potential for storms to be
very slow movers.

...Western Florida Peninsula and the Keys...
A shortwave diving along the Florida Peninsula/Western Gulf will
interact with broad diffluence aloft to maintain deep layer ascent
for convection across the eastern Gulf and into parts of South
Florida and the keys. Mean 0-6km winds of just 5-10 kts will be
aligned SW to NW, anti- parallel to collapsed Corfidi vectors, and
parallel to the Keys. This suggests that convection will repeatedly
build across the Gulf where PWs will be pooled at 2-2.25 inches
within impressive 2000-3000 J/kg MUCAPE leading to 2-4" of
rainfall with locally higher amounts.

...Missouri Valley...
Overnight convection leading into the start of the Day 1 period at
29/12Z prompted a Slight Risk area ahead of the storms. The
expectation is that the storms will weaken...followed by the next
round of storms later today into tonight as a weakening shortwave
crests the monsoon ridge before diving southeast. As the shortwave
moves along a front tonight...it will help accelerate the already
intensifying LLJ to draw robust thermodynamics northward. This will
support organizing clusters of convection or an MCS aligning to
the front as both 0-6km mean winds and Corfidi vectors become
parallel. With rainfall rates likely reaching 1-2"/hr at times, any
training has the potential to produce 2-4" of rain (HREF and REFS
probabilities for 3+" 20-25%) leading to instances of flash
flooding.

Bann/Weiss

Day 2
Valid 12Z Wed Jul 29 2026 - 12Z Thu Jul 30 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE NORTHEAST...

...Northeast...
Rainfall rates and additional rainfall amounts will initially be
heavy early in the period over the eastern portion of the Northeast
before they begin to diminish on Wednesday as an anomalously deep
low pressure system begins to occlude. There should be rainfall
rates around one inch per hour leading to widespread 1-3" of rain
with locally higher amounts.

The latest guidance still depicts a sharp gradient of instability
which may limit the rates in parts of Vermont, New Hampshire and
Maine. This part of the Northeast US should have received less
rainfall with Flash Flood Guidance less likely to have been
compromised. The previous outlook largely had this covered and
changes were fairly minor with this outlook.

...Four Corners States into the Central/Northern Plains...
Monsoonal flow persists with isolated to widely scattered
convection extending from the Four Corners region north and
eastward...perhaps extending as far east as the plains of Colorado.
Some of this rain could fall atop soils saturated from heavy rain
on Tuesday and Tuesday night. It remains possible that a Slight
Risk area may be needed for parts of the High Plains but there was
not enough confidence to do so in this outlook.

...Central Gulf Coast Region into parts of the Southeast...
A cold front stalling along the Gulf Coast will be a focus for slow
moving and training thunderstorms on Wednesday. Guidance continues
to indicate a low-probability threat for at least 3" of rain due to
training of 1-2"/hr rain rates within favorable thermodynamics.
This region can generally tolerate significant rain rates and this
amount of rainfall, but any more pronounced training could result
in isolated flash flood related impacts.

Bann/Weiss

Day 3
Valid 12Z Thu Jul 30 2026 - 12Z Fri Jul 31 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE LOWER MISSOURI AND MID TO UPPER MISSISSIPPI VALLEY...

...Lower Missouri Valley into the Mid-Upper Mississippi Valley...
Shortwave energy will be progressing east southeast as it tracks
across parts of the central and northern plains on Thursday into
Thursday night/early Friday morning. The shortwave energy will be
encountering an increasingly moist and unstable airmass with
precipitable water values in excess of 2 inches being drawn into
the region ahead of the shortwave. Given the MCS/upscale growth
potential with this system, concentrated areas of heavy rain are
expected, especially across the Corn Belt. The Slight risk area
already issued for Thursday still covers the risk....especially
where the global ensemble probabilities of >3" in 12/24 hours are
highest.

...Four Corners States into the Central/Northern Plains...
Monsoonal flow and anomalous deep-layer moisture will maintain an
isolated excessive rainfall risk extending from eastern Arizona
northeastward across much of western and northern New Mexico into
parts of Colorado. The expanding mid/upper level ridge will likely
limit the coverage compared to recent days.

...Central Gulf Coast Region into parts of the Southeast...
Heavy rainfall is expected along a front associated with a low
pressure system which will be pulling away from New England.
Heavy rainfall with some potential of flooding will be focused
along and near the front...especially over parts of Florida and
Georgia line.

Bann

Day 4 and Day 5

Valid 12Z Fri Jul 31 2026 - 12Z Sun Aug 02 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FRIDAY ACROSS
PARTS OF THE MID AND UPPER MISSISSIPPI, AND ON SATURDAY OVER
PORTIONS OF THE LOWER OHIO VALLEY, TENNESSEE VALLEY, AND DEEP
SOUTH...

...Mississippi Valley-Ohio Valley-Tennessee Valley-Deep South...
On Day 4 (Friday-Friday night), minor changes were made to
yesterday's Day 5 ERO, including refinements to the Slight Risk
area over parts of the Mid-Upper MS Valley, based on the latest
(00Z) global deterministic and probabilistic QPFs. The operational
models continue to show max 24hr totals in the 3-5" range,
particularly over IA-southeast MN-southwest WI, though again with
some spatial spread in the guidance. 00Z Operational ECMWF has a
bit more areal coverage of the 3+ inch totals, while the ECENS QPF
exceedance probabilities have once again come up from the previous
run. Based on the latest guidance, along with the most recent ECMWF
EFI output (EFI values aoa 0.6), have nudged the southern portion
of the Slight Risk area a little farther north across the Mid MS
Valley.

On Day 5 (Saturday-Saturday night), the globals continue to show a
fairly vigorous 500 mb trough/embedded shortwave energy slowly pivoting
into the Mid MS Valley. There isn't as strong of a signal in the
QPF guidance compared to the previous couple of days; however, the
amplifying upper level trough (favorable Qs forcing and increasing
effective bulk shear) will combine with a favorable thermodynamic
profile (ML CAPEs 1000-2000 J/Kg along a swath of 1.8-2.1" PWs) to
generate organized heavy rainfall threat across western portions
of the Lower OH Valley into the TN Valley and perhaps as far south
as southern AL, depending on how far south the upper shortwave and
favorable 0-6KM bulk shear can get. Concern within this area will
be heavy rainfall rates (2+ in/hr) given the thermodynamic profile,
along with the potential for cell training of convection as the
upper shortwave begins to stall and the low-level inflow out ahead
of it increases up and aligns more parallel to the mean 850-300 mb
flow. Because of these factors, we felt that a Slight Risk was
warranted.

...Four Corners States into the Southern-Central High Plains...
Monsoonal flow and anomalous deep-layer moisture will maintain a
Marginal (isolated) excessive rainfall risk over eastern AZ and
much of NM into much of CO. The expanding mid/upper level ridge
(600dm heights at 500 mb) will likely limit the coverage compared
to recent days, especially on Friday.

...Central Gulf Coast Region into parts of the Southeast...
Heavy rainfall is expected along the New England cyclone's trailing
front near the FL/GA border, the front that will become more
quasi-stationary Thu-Fri before lifting lifting back north on Sat
ahead of the approaching upper trough. Deep-layer moisture and
instability should be more than sufficient and the guidance shows
sufficient effective bulk shear (0-6km magnitudes generally over 20
kts) for more organized/persistent convective organization. As a
result, have maintained the inherited Marginal Risk on Day 4 (Fri-
Fri night), with a similar Marginal Risk area on Day 5 (Sat-Sat
night).

Hurley

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!_eXAlg75DZMAbx5L9t0-tUYMLGkeqrJejIsoIa_KGTOazIx5qrTFY1fdLD0kSV8JiXb8dUvfu1KQ9b4UieTZvLQOn3M$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!_eXAlg75DZMAbx5L9t0-tUYMLGkeqrJejIsoIa_KGTOazIx5qrTFY1fdLD0kSV8JiXb8dUvfu1KQ9b4UieTZOtU9Z2o$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!_eXAlg75DZMAbx5L9t0-tUYMLGkeqrJejIsoIa_KGTOazIx5qrTFY1fdLD0kSV8JiXb8dUvfu1KQ9b4UieTZVYs-Z9c$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

From COD Weather Processor @1:2320/107 to All on Tue Jul 28 15:58:32 2026

FOUS30 KWBC 281558
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1158 AM EDT Tue Jul 28 2026

Day 1
Valid 16Z Tue Jul 28 2026 - 12Z Wed Jul 29 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR PARTS OF
EASTERN PENNSYLVANIA, NEW JERSEY, SOUTHERN NEW YORK, AND FAR
WESTERN CONNECTICUT...

...Mid Atlantic and Northeast...
A significant flash flooding day is expected across portions of the
Mid Atlantic and Northeast. Convection is rapidly initiating
already between 15-16Z across much of the region, and should become
more widespread by early-mid afternoon. Growing instability in
areas of clearing to the southeast of ongoing rain, and increasing
PWs (likely to approach 2 inches in the Moderate Risk area by 21Z)
should support increasingly intense rain rates by this afternoon.
As convection becomes more widespread, there should also be larger
clusters that develop. The combination of these factors should
yield corridors where intense rain rates can persist in certain
areas for 2-3 hours, and may yield locally extreme rainfall. Almost
every available hi-res model shows at least one localized max of 5
or more inches of rainfall in 6 hours or less. Hourly rain rates
appear likely to exceed 2 inches in the most organized convective
clusters, and could even reach 3 inches. Therefore, the expectation
is for numerous cases of flash flooding associated with the high
rain rates from this afternoon into the early evening, with the
potential for locally significant flash flooding. Given the early
initiation of convection, there is considerable concern for impacts
during the evening commute in the populous urban centers of the
Northeast corridor.

There will be a transition in the convective pattern as we reach
the overnight hours. A strong mid-level vort max, very evident in
GOES East satellite channels across north-central Pennsylvania, is
likely to induce the development of a surface low somewhere over
the region. The position of this surface low will be critical to
where the threat of flash flooding maximizes during the overnight
period and as we approach 12Z (and the morning commute). Our best
estimate is that this would be favored just southeast of the
current trajectory of the surface low, and near the largest
concentration of afternoon convection. For now that looks like it
will be somewhere from SE PA to C NJ by the 00-06Z time frame, and
lifting northeast toward S NY and CT by 06-12Z. This is where the
latest 14Z HRRR places it, and is consistent with the ECMWF
Ensemble and AIFS/AIFS Ensemble. However, there is still
considerable uncertainty. The reason the position of the low is
important is that instability should decrease while PWs stay quite
high, favoring low-topped and very efficient convective rain bands,
and these would tend to concentrate near and just north/east of the
surface low in an area of maximum mesoscale forcing and low-level
convergence. There are also signs that rain bands will extend north
along an inverted trough, perhaps well up the Hudson Valley and
into Vermont. While the maximum rain rates may slightly decrease
during the overnight period, more into the 1-2 inch per hour range
in the strongest convective bands, there would be greater potential
for persistence, and thus locally extreme rainfall will still be
possible -- the threat will just shift more into far southern and
eastern New York, Long Island, Connecticut, western Massachusetts,
and southern Vermont. It's possible there will be an ongoing rain
band with active flash flooding around the end of the period and in
the transition to Day 2, around the time of the Wednesday morning
commute, particularly from Long Island north into Connecticut and
western Massachusetts.

...Central and Southern Appalachians and Virginia...
A broader Marginal Risk area was maintained from southern and
western Maryland south into Virginia, northern North Carolina, and
the central and southern Appalachians. A more conditional threat of
localized heavy rainfall and flash flooding exists in these areas,
largely due to stronger deep layer mean winds (over 30 knots),
which should keep storm motions relatively fast. Precipitable water
values remaining in the 1.6 inch (at higher elevations) to 2.0 inch
(at lower elevations) range should support high instantaneous rain
rates, which could yield localized heavy rain where any training
could occur. However, the overall pattern does not favor widespread
training, and thus the threat is more conditional.

...Four Corners States...
The primary adjustment was to expand the Slight Risk to include
much of northern Arizona, where probabilities of localized heavy
rainfall have increased. The Marginal Risk was also pushed west in
Utah to account for some signal for slow-moving thunderstorms.
Overall, the previous reasoning still applies. The strongest signal
for heavy rain is in northeast Colorado where precipitable water
values are above the 90th percentile and deep layer mean wind and
Corfidi vector magnitudes are lower (generally 10 knots or less).
Therefore, the greatest concern would be around the time of
convective initiation over higher terrain, and for the several
hours afterward. With bulk shear of 30-40 knots, however, as the
storms become more numerous they should begin to organize into
clusters or lines and begin to establish cold pools and accelerate
eastward onto the Plains, which would eventually reduce the threat
of flash flooding. Further to the southwest (NM, AZ), storm motions
should remain relatively slow and should promote the threat of
isolated flash flooding.

...Western Florida Peninsula and the Keys...
No changes. PREVIOUS DISCUSSION: A shortwave diving along the
Florida Peninsula/Western Gulf will interact with broad diffluence
aloft to maintain deep layer ascent for convection across the
eastern Gulf and into parts of South Florida and the keys. Mean
0-6km winds of just 5-10 kts will be aligned SW to NW, anti-
parallel to collapsed Corfidi vectors, and parallel to the Keys.
This suggests that convection will repeatedly build across the Gulf
where PWs will be pooled at 2-2.25 inches within impressive
2000-3000 J/kg MUCAPE leading to 2-4" of rainfall with locally
higher amounts.

...Missouri Valley...
A Marginal Risk was maintained but the Slight Risk was removed
across this region, given a reduced signal in the hi-res ensemble
guidance for heavy rainfall.

Lamers/Bann

Day 2
Valid 12Z Wed Jul 29 2026 - 12Z Thu Jul 30 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE NORTHEAST...

...Northeast...
Rainfall rates and additional rainfall amounts will initially be
heavy early in the period over the eastern portion of the Northeast
before they begin to diminish on Wednesday as an anomalously deep
low pressure system begins to occlude. There should be rainfall
rates around one inch per hour leading to widespread 1-3" of rain
with locally higher amounts.

The latest guidance still depicts a sharp gradient of instability
which may limit the rates in parts of Vermont, New Hampshire and
Maine. This part of the Northeast US should have received less
rainfall with Flash Flood Guidance less likely to have been
compromised. The previous outlook largely had this covered and
changes were fairly minor with this outlook.

...Four Corners States into the Central/Northern Plains...
Monsoonal flow persists with isolated to widely scattered
convection extending from the Four Corners region north and
eastward...perhaps extending as far east as the plains of Colorado.
Some of this rain could fall atop soils saturated from heavy rain
on Tuesday and Tuesday night. It remains possible that a Slight
Risk area may be needed for parts of the High Plains but there was
not enough confidence to do so in this outlook.

...Central Gulf Coast Region into parts of the Southeast...
A cold front stalling along the Gulf Coast will be a focus for slow
moving and training thunderstorms on Wednesday. Guidance continues
to indicate a low-probability threat for at least 3" of rain due to
training of 1-2"/hr rain rates within favorable thermodynamics.
This region can generally tolerate significant rain rates and this
amount of rainfall, but any more pronounced training could result
in isolated flash flood related impacts.

Bann/Weiss

Day 3
Valid 12Z Thu Jul 30 2026 - 12Z Fri Jul 31 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE LOWER MISSOURI AND MID TO UPPER MISSISSIPPI VALLEY...

...Lower Missouri Valley into the Mid-Upper Mississippi Valley...
Shortwave energy will be progressing east southeast as it tracks
across parts of the central and northern plains on Thursday into
Thursday night/early Friday morning. The shortwave energy will be
encountering an increasingly moist and unstable airmass with
precipitable water values in excess of 2 inches being drawn into
the region ahead of the shortwave. Given the MCS/upscale growth
potential with this system, concentrated areas of heavy rain are
expected, especially across the Corn Belt. The Slight risk area
already issued for Thursday still covers the risk....especially
where the global ensemble probabilities of >3" in 12/24 hours are
highest.

...Four Corners States into the Central/Northern Plains...
Monsoonal flow and anomalous deep-layer moisture will maintain an
isolated excessive rainfall risk extending from eastern Arizona
northeastward across much of western and northern New Mexico into
parts of Colorado. The expanding mid/upper level ridge will likely
limit the coverage compared to recent days.

...Central Gulf Coast Region into parts of the Southeast...
Heavy rainfall is expected along a front associated with a low
pressure system which will be pulling away from New England.
Heavy rainfall with some potential of flooding will be focused
along and near the front...especially over parts of Florida and
Georgia line.

Bann

Day 4 and Day 5

Valid 12Z Fri Jul 31 2026 - 12Z Sun Aug 02 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FRIDAY ACROSS
PARTS OF THE MID AND UPPER MISSISSIPPI, AND ON SATURDAY OVER
PORTIONS OF THE LOWER OHIO VALLEY, TENNESSEE VALLEY, AND DEEP
SOUTH...

...Mississippi Valley-Ohio Valley-Tennessee Valley-Deep South...
On Day 4 (Friday-Friday night), minor changes were made to
yesterday's Day 5 ERO, including refinements to the Slight Risk
area over parts of the Mid-Upper MS Valley, based on the latest
(00Z) global deterministic and probabilistic QPFs. The operational
models continue to show max 24hr totals in the 3-5" range,
particularly over IA-southeast MN-southwest WI, though again with
some spatial spread in the guidance. 00Z Operational ECMWF has a
bit more areal coverage of the 3+ inch totals, while the ECENS QPF
exceedance probabilities have once again come up from the previous
run. Based on the latest guidance, along with the most recent ECMWF
EFI output (EFI values aoa 0.6), have nudged the southern portion
of the Slight Risk area a little farther north across the Mid MS
Valley.

On Day 5 (Saturday-Saturday night), the globals continue to show a
fairly vigorous 500 mb trough/embedded shortwave energy slowly pivoting
into the Mid MS Valley. There isn't as strong of a signal in the
QPF guidance compared to the previous couple of days; however, the
amplifying upper level trough (favorable Qs forcing and increasing
effective bulk shear) will combine with a favorable thermodynamic
profile (ML CAPEs 1000-2000 J/Kg along a swath of 1.8-2.1" PWs) to
generate organized heavy rainfall threat across western portions
of the Lower OH Valley into the TN Valley and perhaps as far south
as southern AL, depending on how far south the upper shortwave and
favorable 0-6KM bulk shear can get. Concern within this area will
be heavy rainfall rates (2+ in/hr) given the thermodynamic profile,
along with the potential for cell training of convection as the
upper shortwave begins to stall and the low-level inflow out ahead
of it increases up and aligns more parallel to the mean 850-300 mb
flow. Because of these factors, we felt that a Slight Risk was
warranted.

...Four Corners States into the Southern-Central High Plains...
Monsoonal flow and anomalous deep-layer moisture will maintain a
Marginal (isolated) excessive rainfall risk over eastern AZ and
much of NM into much of CO. The expanding mid/upper level ridge
(600dm heights at 500 mb) will likely limit the coverage compared
to recent days, especially on Friday.

...Central Gulf Coast Region into parts of the Southeast...
Heavy rainfall is expected along the New England cyclone's trailing
front near the FL/GA border, the front that will become more
quasi-stationary Thu-Fri before lifting lifting back north on Sat
ahead of the approaching upper trough. Deep-layer moisture and
instability should be more than sufficient and the guidance shows
sufficient effective bulk shear (0-6km magnitudes generally over 20
kts) for more organized/persistent convective organization. As a
result, have maintained the inherited Marginal Risk on Day 4 (Fri-
Fri night), with a similar Marginal Risk area on Day 5 (Sat-Sat
night).

Hurley

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt__;!!DZ3fjg!_Lt1AKN-hWVDZdeiwQV57djxhiAUCM4Y5bC3D03Vx1OuQYQbn79hQ6z9_UZhtyb3TWwx68Q3ue2_f68PRhCJ2UOx-fQ$
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt__;!!DZ3fjg!_Lt1AKN-hWVDZdeiwQV57djxhiAUCM4Y5bC3D03Vx1OuQYQbn79hQ6z9_UZhtyb3TWwx68Q3ue2_f68PRhCJ_spT3lQ$
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt__;!!DZ3fjg!_Lt1AKN-hWVDZdeiwQV57djxhiAUCM4Y5bC3D03Vx1OuQYQbn79hQ6z9_UZhtyb3TWwx68Q3ue2_f68PRhCJdLdH6X0$

$$

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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)

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