ACUS01 KWNS 140551
SWODY1
SPC AC 140550

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1250 AM CDT Tue Apr 14 2026

Valid 141200Z - 151200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE MIDWEST...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL
TO SOUTHERN PLAINS AND PARTS OF THE NORTHEAST...

...SUMMARY...
Severe thunderstorms are expected this afternoon through tonight
from the southern Plains to the Great Lakes. Large to very large
hail, a few tornadoes (some strong), and damaging wind gusts will be
possible, particularly across parts of eastern Iowa, northern
Illinois, and southern Wisconsin. Additional severe storms, mainly
producing strong wind gusts, will be possible across parts of the
Northeast this afternoon.

...Synopsis...
An upper wave is evident in recent water-vapor imagery across the
southern Great Basin. This trough will translate east into the
Plains through today, reaching the Great Lakes region by tonight.
This will support slight deepening of a diffuse surface low analyzed
over the central High Plains as it drifts east towards the lower MO
River Valley. Ahead of the low, an expansive warm sector
(characterized by widespread mid to upper 60s dewpoints) remains in
place from the southern Plains northeastward into the upper MS
Valley region. Strong to severe thunderstorms are expected along a
composite outflow boundary/warm front from eastern IA into southern
WI/northern IL as well as along a dryline draped from eastern KS
into OK and TX. Further east, a mid-level wave associated with
ongoing convection over the Great Lakes will support re-intensification/re-development of strong/severe storms across the
Northeast.

...Midwest...
An outflow boundary emanating from the ongoing MCS across the Great
Lakes will likely be draped across the Midwest early this morning.
This boundary is forecast to drift northward within a southerly flow
regime as an effective warm front ahead of the approaching surface
low and upper wave. Latest guidance generally depicts this boundary
stalling across eastern IA into southern WI by late afternoon when
daytime heating and ascent ahead of the upper wave will erode
inhibition and promote convective initiation along the boundary.

Dewpoints in the mid to upper 60s coupled with steep mid-level lapse
rates (already noted in upstream 00z RAOBs) will support MLCAPE
values near 2500 J/kg by late afternoon. Moderate buoyancy combined
with 45-55 knots of effective bulk shear will be highly favorable
for organized convection. Capping at the base of the EML should
initially limit thunderstorm coverage and favor discrete supercells
along the boundary. In addition to very large hail (possibly up to
2-3 inches in diameter), enhanced low-level SRH along the boundary
may support a corridor of locally higher tornado potential,
including the potential for significant tornadoes. With time,
easterly storm motions along the boundary will promote upscale
growth with an increasing wind threat heading into the late evening
hours.

The primary uncertainty will be the location of the boundary by late
afternoon. 30% hail and 10% tornado probabilities were adjusted to
reflect the most likely placement of the boundary based on a
consensus of guidance; however, exact placement of the boundary will
be conditional on the precise evolution of the morning MCS.
Similarly, how quickly upscale growth occurs after initiation may
modulate the duration of the significant hail/tornado threat.

...Kansas into Oklahoma and Texas...
Modest height falls across the central to southern Plains combined
with weak convergence along the dryline will likely support isolated
to perhaps scattered thunderstorms from eastern KS southward into TX
this afternoon. Consensus among latest HREF/REFS guidance is that
initiation is most probable across northwest TX into central OK -
possibly ahead of a subtle mid-level wave, though in reality the
unfocused nature of the broad-scale ascent suggests that initiation
will be possible anywhere along the dryline where low-level
convergence can be maximized. Regardless, ample buoyancy within the
warm sector (2500-3000 J/kg MLCAPE sampled in evening RAOBs) coupled
with 30-40 knots of effective bulk shear will support supercells
with an attendant threat for large hail (possibly exceeding 2 inches
in diameter). Some tornado threat will likely materialize around and
after 00 UTC as the nocturnal jet strengthens and enlarges low-level hodographs.

...Northeast...
A low-amplitude upper wave associated with an ongoing MCS across the
Great Lakes will migrate eastward towards the Northeast through the
day. Residual convection associated with the MCS may linger through
morning before re-intensifying by early afternoon as daytime heating
supports steepening low-level lapse rates and increasing MLCAPE
values (likely up to the 500-1000 J/kg range). While buoyancy will
likely remain weak, 35-40 knot bulk shear through the CAPE-bearing
layer and focused ascent ahead of a low-amplitude upper wave will
likely support organization of convective bands with an attendant
threat for strong to severe winds.

..Moore/Wendt.. 04/14/2026

$$

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ACUS01 KWNS 141239
SWODY1
SPC AC 141237

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0737 AM CDT Tue Apr 14 2026

Valid 141300Z - 151200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR IOWA INTO
THE SOUTHERN GREAT LAKES AND PORTIONS OF OKLAHOMA...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE
NORTHEAST...

...SUMMARY...
Severe thunderstorms are expected this afternoon through tonight
from the southern Plains into the Midwest. Large to giant hail,
several tornadoes (some strong), and severe gusts will be possible, particularly from Iowa into the southern Great Lakes.

...Midwest...
An MCV near the IL-IN border this morning and southward-moving
outflow are linked to thunderstorms over parts of the eastern Corn
Belt. This outflow boundary will likely stall with the western
portion of the boundary advancing northward within a strengthening
warm conveyor this afternoon. Guidance generally depicts this
boundary stalling across eastern IA into southern WI by late
afternoon when daytime heating and ascent ahead of the upper wave
will erode inhibition and promote convective initiation along the
boundary. A moist airmass upstream over the lower MO Valley will
advect northeast beneath steep 700-500 mb lapse rates (reference the
12 UTC Topeka, KS raob). MLCAPE at or above 2500 J/kg is forecast
by mid-late afternoon from IA into the IA-WI-IL border vicinity.
Initial storms later this afternoon will rapidly become supercells
with all severe hazards possible. Large to giant hail and an
intense tornado will be possible with the more mature/strongest
supercells where SRH is locally maximized near the boundary.
Upscale growth into a severe cluster is forecast to eventually
evolve during the evening aided by a strong southwesterly LLJ into
the southern Great Lakes. If a supercell develops ahead of the
eastward-moving cluster, a tornado threat could develop as the
boundary layer quickly recovers/destabilizes.

...Kansas into Oklahoma and Texas...
Modest height falls across the central to southern Plains combined
with weak convergence along the dryline will likely support
scattered thunderstorms from eastern KS southward into western north
TX this afternoon into the evening. Aligning with earlier thinking,
strong heating and perhaps weak ascent tied to a subtle mid-level
wave, will favor storm development by 20-22z as convective
inhibition erodes. A very unstable airmass characterized by
2500-3000 J/kg MLCAPE and elongated hodographs will strongly favor
supercells. The strength of low-level shear remains unclear during
the early evening, when the tornado risk could maximize.
Nonetheless, increased confidence in widely scattered to scattered
supercells yielding a risk for large to giant hail prompted an
increase in hail and hail-intensity highlights this outlook update.

...Northeast...
A low-amplitude disturbance associated with an ongoing MCS near Lake
Ontario this morning will move east into the Northeast during the
day. Cloud breaks and low-level warm/moist advection will
contribute to a destabilizing airmass by midday. Veering and
strengthening winds with height will support storm organization,
including the potential for supercells. Eventually a band of storms
is forecast to evolve by mid-late afternoon with wind damage being
the primary risk. Have introduced low hail/tornado probabilities to
account for hazards associated with supercells.

..Smith/Dean.. 04/14/2026

$$

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ACUS01 KWNS 141632
SWODY1
SPC AC 141630

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1130 AM CDT Tue Apr 14 2026

Valid 141630Z - 151200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE MIDWEST/SOUTHERN GREAT LAKES AND SOUTHERN/CENTRAL PLAINS...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE NORTHEAST...

...SUMMARY...
Severe thunderstorms are expected this afternoon through tonight
from the southern Plains into the Midwest. Large to giant hail,
several tornadoes (some strong), and swaths of severe/damaging gusts
are all likely, particularly from Iowa into the southern Great
Lakes.

...Synopsis...
An active severe weather day is anticipated for much of the
southern/central Plains into the Midwest/Great Lakes and parts of
the Northeast. The primary upper trough centered over the Four
Corners late this morning will eject east-northeastward towards the southern/central Plains by this evening, while a separate mid-level
shortwave trough over the northern Plains/Upper Midwest will also
move east-northeastward across the Upper Great Lakes into Ontario.
Another convectively enhanced low-amplitude shortwave trough will
also develop eastward across the Lower Great Lakes into the
Northeast.

Recent surface analysis indicates multiple surface lows, with one
over southern Ontario and another over southeast NE/northeast KS. A
seasonably rich/moist low-level airmass exists to the south of a
front extending between these two lows, with surface dewpoints
already in the low to mid 60s across much of the southern/central
Plains to the east of a dryline. Both the dryline in the
southern/central Plains and developing warm front in the
Midwest/southern Great Lakes will likely serve as foci for intense thunderstorms this afternoon and evening, including the potential
for several supercells.

...Midwest/Ohio Valley/Great Lakes...
A complex scenario for severe thunderstorms remains apparent across
the Midwest/OH Valley into the southern Great Lakes today, with
multiple outflow boundaries from earlier convection rendering
greater than usual uncertainty with the southward extent of possible thunderstorm development in IL/IN/OH. In general, continued
low-level warm advection from the central Plains into the Midwest/OH
Valley will support a moistening/destabilizing airmass through the
afternoon as a northern-stream shortwave trough moves eastward
across the Upper Midwest. A surface warm front will extend
northeastward from a weak surface low in IA across southern WI and
Lower MI. It still appears likely that multiple intense supercells
will develop by 20-21Z along/near this boundary in IA/southern
WI/northern IL in a very favorable airmass for significant severe
hail given strong deep-layer shear and the presence of steep
mid-level lapse rates. Low-level shear is expected to gradually
strengthen through the evening in tandem with a modestly increasing south-southwesterly low-level jet.

Any supercells than can remain on the warm/south side of the front
will be capable of producing tornadoes, a few of which could be
strong (EF-2/3). Some consideration was given to including greater
tornado probabilities and a Moderate Risk (level 4 of 5) focused
across southern WI/far northern IL. But, convection may have a
tendency to grow upscale fairly quickly this evening, so confidence
was not high enough for a categorical upgrade at this time.
Regardless, very large to giant hail (potentially up to 3-4 inches
in diameter) will be a threat with sustained supercells, and a swath
of severe/damaging winds appears likely with a convective cluster
spreading eastward across southern Lower MI this evening into
tonight.

A somewhat separate area of severe potential should also exist
farther south across central IL into IN/OH this afternoon and
evening. Greater low-level moisture and related instability are
expected to exist across these areas compared to locations farther
north. While large-scale forcing should remain fairly weak/nebulous
across this region, a remnant outflow boundary may provide a focus
for supercell development across central IL into IN by 20-21Z. Have
expanded the Slight Risk for large hail, damaging winds, and perhaps
a few tornadoes southward across these areas to account for this
still somewhat uncertain potential.

...Southern/Central Plains...
12Z observed soundings from DRT/MAF/FWD/OUN/TOP show the presence of
steep mid-level lapse rates atop rich low-level moisture (generally
14-15 g/kg mean mixing ratios) along/east of the surface dryline.
Southwesterly mid-level flow and modest ascent preceding the upper
trough over the Southwest/southern Rockies will gradually overspread
the warm sector by mid to late afternoon. Moderate to strong
instability (MLCAPE around 2000-3000 J/kg, locally stronger
possible) and 35-45 kt of deep-layer shear will support multiple
intense supercells. Explosive convective initiation across parts of
western OK into south-central/southeast KS is expected by 20-21Z as
lingering MLCIN erodes with filtered daytime heating and as
convective temperatures are breached.

The overall thermodynamic and kinematic environment appears quite
favorable for very large to potentially giant hail (up to 3-4 inches
in diameter) with any supercells that spread east-northeastward
through the afternoon/evening. A gradually strengthening low-level
jet across OK/KS by 00Z will also support a threat for a few
tornadoes, a couple of which could be strong as low-level hodographs
become enlarged. Gradual upscale growth/clustering should occur with
time through the evening, with some risk for severe/damaging winds.
The Enhanced Risk has been expanded a bit northeastward into south-central/southeast KS for a focused severe wind corridor.
Farther south along the length of the dryline in TX, isolated to
scattered supercells may develop this afternoon and evening, with a
risk for mainly large to very large hail and occasional severe
gusts.

...Northeast...
Ongoing convection across southern Ontario and the Lower Great Lakes
will continue to track eastward this afternoon into NY and parts of
New England in tandem with a low-amplitude shortwave trough. Gradual
clearing of low/mid-level clouds has already encouraged surface
temperatures to warm into the 70s along/south of west-east oriented
front. Thunderstorms are expected to gradually increase in coverage
and intensity as weak to locally moderate instability and strong
deep-layer shear support organized updrafts, including the potential
for some supercells initially. The greatest severe risk will
probably be scattered damaging winds given a tendency for convection
to consolidate into one or more clusters. But, an isolated severe
hail threat may exist with any sustained supercell, along with some
chance for a tornado or two near the front where low-level shear
will be locally enhanced.

..Gleason/Chalmers.. 04/14/2026

$$

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ACUS01 KWNS 141938
SWODY1
SPC AC 141936

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0236 PM CDT Tue Apr 14 2026

Valid 142000Z - 151200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE MIDWEST/SOUTHERN GREAT LAKES AND SOUTHERN/CENTRAL PLAINS...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE NORTHEAST...

...SUMMARY...
Severe thunderstorms are expected this afternoon through tonight
from the southern Plains into the Midwest. Large to giant hail,
several tornadoes (some strong), and swaths of severe/damaging gusts
are all likely, particularly from Iowa into the southern Great
Lakes.

...20Z Update...
A complex yet active severe weather day remains in the forecast for
portions of the Midwest-OH Valley into the Southern Plains this
afternoon into early tonight. While several lines were slightly
adjusted to account for the latest guidance consensus, the following substantial changes and/or decisions were made:

1.) 30 percent wind probabilities were expanded southwestward into
southwest and central OK to account for the possibility of more
rapid upscale growth into one or more wind-producing MCSs or linear
segments.

2.) Category 1/Marginal Risk probabilities for severe wind and hail
were expanded west-southwest into NE along a frontal boundary to
account for two possible scenarios. First, an isolated strong storm
may develop within the next few hours along the boundary as a
consequence of strong diurnal heating. Second, late tonight, there
is low potential for gravity-wave associated convection on the
immediate cool side of the frontal boundary, atop a stable boundary
layer.

3.) Confidence is still too low for supercells across the Midwest to
remain discrete for long periods of time, which would warrant a
Categorical Moderate risk upgrade. Nonetheless, should a dominant
supercell become sustained and discrete for at least a few hours,
especially along the warm front over northeast IA into southern WI,
a sustained and intense tornado will be possible.

The rest of the forecast (see below) remains on track.

..Squitieri.. 04/14/2026

.PREV DISCUSSION... /ISSUED 1130 AM CDT Tue Apr 14 2026/

...Synopsis...
An active severe weather day is anticipated for much of the
southern/central Plains into the Midwest/Great Lakes and parts of
the Northeast. The primary upper trough centered over the Four
Corners late this morning will eject east-northeastward towards the southern/central Plains by this evening, while a separate mid-level
shortwave trough over the northern Plains/Upper Midwest will also
move east-northeastward across the Upper Great Lakes into Ontario.
Another convectively enhanced low-amplitude shortwave trough will
also develop eastward across the Lower Great Lakes into the
Northeast.

Recent surface analysis indicates multiple surface lows, with one
over southern Ontario and another over southeast NE/northeast KS. A
seasonably rich/moist low-level airmass exists to the south of a
front extending between these two lows, with surface dewpoints
already in the low to mid 60s across much of the southern/central
Plains to the east of a dryline. Both the dryline in the
southern/central Plains and developing warm front in the
Midwest/southern Great Lakes will likely serve as foci for intense thunderstorms this afternoon and evening, including the potential
for several supercells.

...Midwest/Ohio Valley/Great Lakes...
A complex scenario for severe thunderstorms remains apparent across
the Midwest/OH Valley into the southern Great Lakes today, with
multiple outflow boundaries from earlier convection rendering
greater than usual uncertainty with the southward extent of possible thunderstorm development in IL/IN/OH. In general, continued
low-level warm advection from the central Plains into the Midwest/OH
Valley will support a moistening/destabilizing airmass through the
afternoon as a northern-stream shortwave trough moves eastward
across the Upper Midwest. A surface warm front will extend
northeastward from a weak surface low in IA across southern WI and
Lower MI. It still appears likely that multiple intense supercells
will develop by 20-21Z along/near this boundary in IA/southern
WI/northern IL in a very favorable airmass for significant severe
hail given strong deep-layer shear and the presence of steep
mid-level lapse rates. Low-level shear is expected to gradually
strengthen through the evening in tandem with a modestly increasing south-southwesterly low-level jet.

Any supercells than can remain on the warm/south side of the front
will be capable of producing tornadoes, a few of which could be
strong (EF-2/3). Some consideration was given to including greater
tornado probabilities and a Moderate Risk (level 4 of 5) focused
across southern WI/far northern IL. But, convection may have a
tendency to grow upscale fairly quickly this evening, so confidence
was not high enough for a categorical upgrade at this time.
Regardless, very large to giant hail (potentially up to 3-4 inches
in diameter) will be a threat with sustained supercells, and a swath
of severe/damaging winds appears likely with a convective cluster
spreading eastward across southern Lower MI this evening into
tonight.

A somewhat separate area of severe potential should also exist
farther south across central IL into IN/OH this afternoon and
evening. Greater low-level moisture and related instability are
expected to exist across these areas compared to locations farther
north. While large-scale forcing should remain fairly weak/nebulous
across this region, a remnant outflow boundary may provide a focus
for supercell development across central IL into IN by 20-21Z. Have
expanded the Slight Risk for large hail, damaging winds, and perhaps
a few tornadoes southward across these areas to account for this
still somewhat uncertain potential.

...Southern/Central Plains...
12Z observed soundings from DRT/MAF/FWD/OUN/TOP show the presence of
steep mid-level lapse rates atop rich low-level moisture (generally
14-15 g/kg mean mixing ratios) along/east of the surface dryline.
Southwesterly mid-level flow and modest ascent preceding the upper
trough over the Southwest/southern Rockies will gradually overspread
the warm sector by mid to late afternoon. Moderate to strong
instability (MLCAPE around 2000-3000 J/kg, locally stronger
possible) and 35-45 kt of deep-layer shear will support multiple
intense supercells. Explosive convective initiation across parts of
western OK into south-central/southeast KS is expected by 20-21Z as
lingering MLCIN erodes with filtered daytime heating and as
convective temperatures are breached.

The overall thermodynamic and kinematic environment appears quite
favorable for very large to potentially giant hail (up to 3-4 inches
in diameter) with any supercells that spread east-northeastward
through the afternoon/evening. A gradually strengthening low-level
jet across OK/KS by 00Z will also support a threat for a few
tornadoes, a couple of which could be strong as low-level hodographs
become enlarged. Gradual upscale growth/clustering should occur with
time through the evening, with some risk for severe/damaging winds.
The Enhanced Risk has been expanded a bit northeastward into south-central/southeast KS for a focused severe wind corridor.
Farther south along the length of the dryline in TX, isolated to
scattered supercells may develop this afternoon and evening, with a
risk for mainly large to very large hail and occasional severe
gusts.

...Northeast...
Ongoing convection across southern Ontario and the Lower Great Lakes
will continue to track eastward this afternoon into NY and parts of
New England in tandem with a low-amplitude shortwave trough. Gradual
clearing of low/mid-level clouds has already encouraged surface
temperatures to warm into the 70s along/south of west-east oriented
front. Thunderstorms are expected to gradually increase in coverage
and intensity as weak to locally moderate instability and strong
deep-layer shear support organized updrafts, including the potential
for some supercells initially. The greatest severe risk will
probably be scattered damaging winds given a tendency for convection
to consolidate into one or more clusters. But, an isolated severe
hail threat may exist with any sustained supercell, along with some
chance for a tornado or two near the front where low-level shear
will be locally enhanced.

$$

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ACUS01 KWNS 150056
SWODY1
SPC AC 150054

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0754 PM CDT Tue Apr 14 2026

Valid 150100Z - 151200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROS PORTIONS
OF THE GREAT LAKES REGION...

...SUMMARY...
Severe thunderstorms are expected through tonight from the southern
Plains into the Midwest. Large hail, several tornadoes (some
strong), and swaths of severe/damaging gusts are all likely,
particularly from eastern Iowa into the southern Great Lakes.

...Synopsis...
Scattered discrete/semi-discrete supercells are ongoing across
eastern Iowa, far northern Illinois, and southern Wisconsin along a
diffuse warm frontal zone stretching eastward from weak surface low
analyzed over eastern NE/western IA. The primary severe risk through
the overnight hours will be associated with this activity as it
spreads southeast through early morning. Further south across the central/southern Plains, poorly organized convection casts
uncertainty in the nocturnal severe threat; however, a favorable
environment will remain in place through Wednesday morning and could
support severe convection.

...Midwest/Great Lakes...
01 UTC regional radar mosaics show semi-discrete supercells ongoing
across far eastern IA, northern IL, and southern WI with the early
stages of upscale growth evident as storms interactions increase.
This trend will continue through the overnight hours as this
activity propagates east/southeast into lower MI and northern IN.
The recent 00z DVN RAOB sampled a convective environment highly
favorable for organized convection, which will maintain the
potential for significant hail and tornadoes in the near term (most
likely through 03 UTC) before a full transition to a linear mode
takes place. Once this transition occurs, severe winds (including
the potential for significant gusts in excess of 75 mph) and
embedded circulations appear probable for areas downstream.

...Southern Iowa into Kansas...
Thunderstorm development along a southward sagging cold front is
anticipated in the coming hours across northeast KS into southern
IA. Regional soundings sampled adequate buoyancy and strong
deep-layer wind shear (around 50 knots) that will likely support
organized convection along the front for a few hours. Storm motions
along the boundary may foster clustering/upscale growth, but a
severe wind, hail, and perhaps tornado threat is expected to
materialize through the night.

...Oklahoma into Texas...
Convective evolution thus far across western OK into northwest TX
has been relatively lackluster given the otherwise buoyant and
strongly sheared environment sampled by the 00z OUN sounding. This
is likely due to expansive convective outflows resulting in
undercutting and clustered storm modes as well as the presence of a
subsidence inversion (also noted in the 00z sounding). It remains
unclear whether or not this activity will be able to re-intensify
through the late evening hours given. However, strengthening flow
fields through 06 UTC may support some degree of improved
organization and a more robust severe threat. This potential is
hinted by recent HRRR solutions, but overall confidence is limited.
Based on these trends, opted to remove the 30% hail/wind
probabilities given low confidence in severe coverage. Further south
into western TX, attempts at sustained convection have been noted
over the past hour along the dryline, but downstream inhibition may
limit overall storm coverage.

..Moore.. 04/15/2026

$$

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ACUS01 KWNS 150554
SWODY1
SPC AC 150553

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1253 AM CDT Wed Apr 15 2026

Valid 151200Z - 161200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE
SOUTHERN PLAINS...MIDWEST...AND INTO THE GREAT LAKES...

...SUMMARY...
Severe thunderstorms posing a risk for large hail, strong wind
gusts, and a couple of tornadoes will be possible across portions of
the southern Plains toward the Great Lakes this afternoon and
evening.

...Synopsis...
A migratory upper-level wave is evident in water-vapor imagery over
northern Mexico. This feature will lift northeastward into the
Plains through the day, resulting in the eastward progression of a
modest surface cyclone from the central High Plains into eastern NE
by late afternoon. A broad, uncapped, and moderately sheared warm
sector will be in place from the southern Plains into the mid-MS
Valley and eastward into the Great Lakes/OH Valley. Strong to severe thunderstorm development appears probable across much of this warm
sector, whether induced by ascent ahead of the primary upper wave or
by localized mesoscale boundaries.

...Iowa and northern Missouri...
Thunderstorm development appears likely by late afternoon from
central IA into northern MO in the vicinity of the surface low.
Stronger mid-level height falls compared to previous days lends
higher confidence in thunderstorm development, and 50-60 knot 500 mb
flow overspreading much of the warm sector will support organized
convection, including the potential for splitting supercells capable
of very large hail and tornadoes across IA and northern MO. A
focused zone of higher tornado potential may emerge roughly along
the I-80 corridor where backed low-level winds along the effective
warm front will locally augment SRH and could support a strong
tornado. HREF/REFS guidance both show the strongest UH signals
across this zone, warranting higher (5%) tornado probabilities.

...Ozarks into Oklahoma and north Texas...
Further south, initially discrete cells are anticipated along the
dryline from southeast KS into OK and north TX by mid-afternoon.
Despite somewhat higher confidence in storm development compared to
previous days, mean flow vectors along the boundary may promote
clustering and upscale growth within a few hours after initiation.
This scenario appears to be reflected in recent HREF/REFS guidance
in the form of numerous, but weak, UH streaks, as well as in
deterministic CAM solutions that depict one or more convective bands
emerging by early evening. Additionally, guidance hints at the
potential for morning convection across parts of OK and the Ozark
Plateau. It remains unclear what influence - if any- this activity
will have on the southern Plains warm sector or if any outflow
boundaries can emerge and focus a higher severe threat along
mesoscale corridors. Given these uncertainties, all severe
probabilities were expanded to account for the fairly wide envelope
of potential outcomes, most of which will likely feature the
potential for severe hail, wind, and tornadoes.

...Great Lakes into New England...
The combination of low to mid-60s dewpoints and the eastward
advection of an EML will support MLCAPE values upwards of 1000-1500
J/kg across much of the Great Lakes region with gradually
diminishing buoyancy with eastward extent towards the New England
coast. Aloft, 40-50 knot westerly mid-level winds will remain in
place within the crest of a modest ridge, establishing a zonal
corridor of a buoyant and moderately sheared environment. It appears
likely that multiple outflow boundaries and/or mid-level
perturbations associated with upstream MCSs across MI, AR, and IA
will likely reside within the warm sector by peak heating.
Thunderstorm development along or in the vicinity of these features
will support multiple corridors of strong to severe convection. This
scenario is depicted by most recent CAMs, which show multiple
convection bands traversing the warm sector through early evening.
However, exactly where these bands will become established (and
where corridors of higher severe potential will emerge) remains
uncertain given variance in recent guidance.

..Moore/Wendt.. 04/15/2026

$$

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ACUS01 KWNS 151247
SWODY1
SPC AC 151246

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0746 AM CDT Wed Apr 15 2026

Valid 151300Z - 161200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE SOUTHERN
PLAINS INTO THE MIDWEST AND SOUTHERN GREAT LAKES...

...SUMMARY...
Severe thunderstorms posing a risk for large hail to very large
hail, severe gusts, and a couple of tornadoes will be possible
across portions of the southern Plains toward the Great Lakes this
afternoon and evening.

...Synopsis...
Water-vapor imagery this morning shows an upper trough from the
eastern Dakotas south-southwestward into the southern Rockies. A
few disturbances will migrate eastward coincident with the trough
with the most notable being over the central High Plains this
morning. The aforementioned disturbance will move east reaching the
mid-upper MS Valley with the trailing southern extent of the wave
moving into the MO Ozarks and OK by daybreak Thursday. A weak
diffuse low will move from northern KS to the southwest Great Lakes
by late tonight. Farther east, an MCV near MO-IL will translate
east and become perhaps a focus for storm activity later this
afternoon across OH-PA. A rather complex forecast is apparent due
in large part to considerable convection and related outflow
permeating the warm sector overnight across much of the Slight-Risk
area.

...Iowa into the mid MS Valley...
In the wake of showers/storms this morning from IA southward into
MO, a moist and weakly capped airmass will destabilize through early
afternoon. The eastward approach of the mid-level disturbance will
likely contribute towards scattered thunderstorms developing 19-21z
from near the weak low eastward along the composite outflow/frontal
zone into IL-WI and southward into MO within a weakly capped warm
sector. Forecast soundings show straight-line hodographs over IA
with sizable CAPE in the hail growth zone. The potential for
splitting supercells appears evident with the stronger storms
capable of very large hail and perhaps some tornado risk across IA
and northern MO.

...Ozarks into Oklahoma and north Texas...
Morning raobs showed steep 700-500 mb lapse rates (7.5-8 deg C/km)
atop a seasonably very moist return-flow airmass. Models generally
show storm development near the dryline by mid afternoon with
initial development becoming supercellular. Large to very large
hail will be possible with the stronger updrafts. Residual outflow
from overnight convection moving into the Ozarks may play a role in
enhancing low-level shear later today. Forecast soundings show
somewhat limited low-level hodographs with a tendency for a
veer-back-veer signature. Additional storms will favor some
clustering and upscale growth with time due in part to the forecast
hodographs. Nonetheless, all hazards will be possible at least
through the early convective life cycle before the possibility for
wind damage and linear structures perhaps evolve during the evening.

...Southern Great Lakes into the Northeast...
The remnants of an overnight squall line are moving east across
NY-PA this morning with a trailing outflow boundary extending
westward into OH and northeast IN. Moist low levels and the
eastward advection of steeper mid-level lapse rates will act to
destabilize the southern Great Lakes into western PA through midday
and into the afternoon. Forcing for ascent and enhancement of flow
associated with the MCV will potentially focus thunderstorms and aid
in their organization potential beginning this afternoon.
Considerable uncertainty remains regarding this scenario and whether
a mesoscale corridor of higher tornado probabilities is needed
(i.e., northeast OH). Will defer to later outlooks to where perhaps
mesoscale corridors of greater wind/hail threat and an isolated risk
for a couple of tornadoes could develop.

..Smith/Dean.. 04/15/2026

$$

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ACUS01 KWNS 151632
SWODY1
SPC AC 151630

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1130 AM CDT Wed Apr 15 2026

Valid 151630Z - 161200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTHERN/CENTRAL PLAINS INTO THE MIDWEST/OHIO VALLEY AND
SOUTHERN GREAT LAKES...

...SUMMARY...
Severe thunderstorms posing a risk for large to very large hail,
damaging winds, and perhaps a few tornadoes will be possible across
parts of the southern/central Plains into the Midwest/Ohio Valley
and southern Great Lakes this afternoon and evening.

...Synopsis...
Severe potential across the broad warm sector will be complicated by
ongoing thunderstorms/MCVs and associated cloud cover. A neutral to
positively tilted upper trough will eject northeastward across the southern/central Plains today, with a broad zone of enhanced
mid-level southwesterly winds extending over much of TX/OK into the
Midwest/OH Valley and Great Lakes. At the surface, a weak low over
southeast NE late this morning is forecast to develop slowly
northeastward across IA through the afternoon and evening, with a quasi-stationary front extending northeastward from this low towards
southern WI/Lower MI. A dryline extends southward across KS/OK into
west TX. Multiple MCVs related to ongoing/earlier convection are
also noted in recent visible satellite/radar imagery, and these
features may aid additional convective development this afternoon.

...Iowa into Missouri...
Forcing for ascent associated with the ejecting upper trough will
overspread the front draped across IA this afternoon. Ongoing
supercell in western IA and cloudiness near the front late this
morning cast some uncertainty on the degree of destabilization that
will occur this afternoon, and the overall intensity of convection.
Still, expectations are for additional robust thunderstorms to
eventually develop by 19-21Z along/near the front in IA, with steep
mid-level lapse rates noted on the observed 12Z TOP sounding
supporting moderate to locally strong MLCAPE even if
clouds/precipitation hinder daytime heating to some extent. Various
NAM/RAP forecast soundings show elongated/nearly straight hodographs
at mid/upper levels and 50+ kt of deep-layer shear, which will be
favorable for upper-level/anvil venting and hail production with any
supercells that form. Large to very large hail will be a concern
with initially discrete convection. But, some tendency for
clustering and movement north of the surface front casts
considerable uncertainty on the wind/tornado potential. Even so,
some chance for a few tornadoes and scattered damaging winds may
exist along/south of the front across IA into MO with any convection
that can develop east of the dryline.

...Southern Plains into the Ozarks and Mid Mississippi Valley...
A seasonably moist low-level airmass remains in place across the
southern Plains into the Ozarks and mid MS Valley, with observed 12Z
soundings from FWD/OUN/SGF indicating mean mixing ratios ranging
12-13.6 g/kg. However, even with steep mid-level lapse rates noted
across TX/OK, profiles are fairly saturated at mid/upper levels, and
plentiful cloud cover is present in recent visible satellite imagery
across these regions. It still appears likely that surface-based
thunderstorms will develop this afternoon (around 19-21Z) along/east
of the dryline as MLCIN gradually erodes ahead of the ejecting upper
trough. But, overall evolution remains somewhat unclear, with
potential for messy storm modes/interactions fairly early in the
convective life cycle given a large degree of boundary-parallel flow
in low/mid levels. Initial supercells should pose a threat for
mainly large to very large hail (isolated 2+ inches in diameter),
before clustering and an increase in damaging wind potential occurs.
The tornado threat is less clear, as stronger low-level flow will
tend to remain focused farther north into the Midwest. Still,
sufficient low-level shear should exist this afternoon and evening
to support a threat for a few tornadoes with both supercells and
embedded within clusters.

...Midwest/Ohio Valley into Western Pennsylvania...
An MCV evident over eastern IL/western IN will continue to track
eastward into northern IN and eventually OH this afternoon and
evening. Ongoing thunderstorms associated with this MCV have
remained sub-severe through much of the morning. But, gradual
destabilization of the already moist low-level airmass downstream
should support some uptick in convective coverage and intensity
across the OH Valley by mid to late afternoon. Localized enhancement
to the west-southwesterly low-level winds should focus across parts
of northern OH and vicinity, where somewhat greater low-level shear
and tornado potential may exist. Strong deep-layer shear will easily
support organized convection, including the potential for supercells
with a threat for large hail, damaging winds, and perhaps a couple
of tornadoes. Additional thunderstorms may eventually develop
eastward from the mid MS Valley into IL/IN in association with
another MCV. Large hail, damaging winds, and a tornado or two may
also occur with this activity, if it develops.

..Gleason/Squitieri.. 04/15/2026

$$

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ACUS01 KWNS 151957
SWODY1
SPC AC 151955

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0255 PM CDT Wed Apr 15 2026

Valid 152000Z - 161200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PARTS OF THE
SOUTHERN/CENTRAL PLAINS INTO THE MIDWEST/OHIO VALLEY AND SOUTHERN
GREAT LAKES...

...SUMMARY...
Severe thunderstorms posing a risk for large to very large hail,
damaging winds, and perhaps a few tornadoes will be possible across
parts of the southern/central Plains into the Midwest/Ohio Valley
and southern Great Lakes this afternoon and evening.

...20Z Update...

...Mid MS Valley through the Ozarks into the Southern Plains...
Recent surface analysis places a low in the NE/IA/MO border
intersection vicinity, with a dry line extending southwestward from
this low through eastern KS, western OK, and northwest TX. As
mentioned in MCD #448, the elevated supercell ongoing across central
IA could begin to interact with an environment more supportive of
surface-based storms. If a transition to surface-based is realized,
an increased potential for damaging gusts and a tornado will exist.
New development is also beginning across central IA, along the
outflow extending southwestward for this supercell. Hail remains the
primary risk across the region, both with the ongoing supercell and
any new development along its outflow.

Increasing thunderstorm coverage is still expected tonight along the
dryline as it shifts eastward, beginning across northwest TX and
central OK now before expanding northward into MO, and potentially southwestward into more of southwest TX later. Large hail remains
the primary threat with this initially more cellular activity. Some
very large hail (i.e. 2"+ in diameter) is possible. Over time,
storm interactions and/or upscale growth is anticipated, with a
trend towards a threat for more damaging gusts. Tornado threat
remains low, largely due weakness in the low to mid-level flow and
convective mode issues. However, some modest strengthening of the
low-level flow should exist this afternoon and evening from eastern
OK into the mid MS Valley, supporting a threat for a few tornadoes
with both supercells and embedded within clusters.

...OH Valley...
Severe Thunderstorm Watch #120 is currently ongoing from far
southeast Lower MI across northern OH into far northwest PA. Here, a
mix of clusters and supercells pose a threat for scattered damaging
winds and large hail as they spread quickly east-northeastward this
afternoon and evening. A tornado or two is also possible.

..Mosier.. 04/15/2026

.PREV DISCUSSION... /ISSUED 1130 AM CDT Wed Apr 15 2026/

...Synopsis...
Severe potential across the broad warm sector will be complicated by
ongoing thunderstorms/MCVs and associated cloud cover. A neutral to
positively tilted upper trough will eject northeastward across the southern/central Plains today, with a broad zone of enhanced
mid-level southwesterly winds extending over much of TX/OK into the
Midwest/OH Valley and Great Lakes. At the surface, a weak low over
southeast NE late this morning is forecast to develop slowly
northeastward across IA through the afternoon and evening, with a quasi-stationary front extending northeastward from this low towards
southern WI/Lower MI. A dryline extends southward across KS/OK into
west TX. Multiple MCVs related to ongoing/earlier convection are
also noted in recent visible satellite/radar imagery, and these
features may aid additional convective development this afternoon.

...Iowa into Missouri...
Forcing for ascent associated with the ejecting upper trough will
overspread the front draped across IA this afternoon. Ongoing
supercell in western IA and cloudiness near the front late this
morning cast some uncertainty on the degree of destabilization that
will occur this afternoon, and the overall intensity of convection.
Still, expectations are for additional robust thunderstorms to
eventually develop by 19-21Z along/near the front in IA, with steep
mid-level lapse rates noted on the observed 12Z TOP sounding
supporting moderate to locally strong MLCAPE even if
clouds/precipitation hinder daytime heating to some extent. Various
NAM/RAP forecast soundings show elongated/nearly straight hodographs
at mid/upper levels and 50+ kt of deep-layer shear, which will be
favorable for upper-level/anvil venting and hail production with any
supercells that form. Large to very large hail will be a concern
with initially discrete convection. But, some tendency for
clustering and movement north of the surface front casts
considerable uncertainty on the wind/tornado potential. Even so,
some chance for a few tornadoes and scattered damaging winds may
exist along/south of the front across IA into MO with any convection
that can develop east of the dryline.

...Southern Plains into the Ozarks and Mid Mississippi Valley...
A seasonably moist low-level airmass remains in place across the
southern Plains into the Ozarks and mid MS Valley, with observed 12Z
soundings from FWD/OUN/SGF indicating mean mixing ratios ranging
12-13.6 g/kg. However, even with steep mid-level lapse rates noted
across TX/OK, profiles are fairly saturated at mid/upper levels, and
plentiful cloud cover is present in recent visible satellite imagery
across these regions. It still appears likely that surface-based
thunderstorms will develop this afternoon (around 19-21Z) along/east
of the dryline as MLCIN gradually erodes ahead of the ejecting upper
trough. But, overall evolution remains somewhat unclear, with
potential for messy storm modes/interactions fairly early in the
convective life cycle given a large degree of boundary-parallel flow
in low/mid levels. Initial supercells should pose a threat for
mainly large to very large hail (isolated 2+ inches in diameter),
before clustering and an increase in damaging wind potential occurs.
The tornado threat is less clear, as stronger low-level flow will
tend to remain focused farther north into the Midwest. Still,
sufficient low-level shear should exist this afternoon and evening
to support a threat for a few tornadoes with both supercells and
embedded within clusters.

...Midwest/Ohio Valley into Western Pennsylvania...
An MCV evident over eastern IL/western IN will continue to track
eastward into northern IN and eventually OH this afternoon and
evening. Ongoing thunderstorms associated with this MCV have
remained sub-severe through much of the morning. But, gradual
destabilization of the already moist low-level airmass downstream
should support some uptick in convective coverage and intensity
across the OH Valley by mid to late afternoon. Localized enhancement
to the west-southwesterly low-level winds should focus across parts
of northern OH and vicinity, where somewhat greater low-level shear
and tornado potential may exist. Strong deep-layer shear will easily
support organized convection, including the potential for supercells
with a threat for large hail, damaging winds, and perhaps a couple
of tornadoes. Additional thunderstorms may eventually develop
eastward from the mid MS Valley into IL/IN in association with
another MCV. Large hail, damaging winds, and a tornado or two may
also occur with this activity, if it develops.

$$

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ACUS01 KWNS 160058
SWODY1
SPC AC 160057

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0757 PM CDT Wed Apr 15 2026

Valid 160100Z - 161200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING IN A
CORRIDOR FROM THE SOUTHEASTERN GREAT PLAINS THROUGH THE MIDWEST...

...SUMMARY...
Potential for damaging wind gusts could still increase a bit with
developing clusters of storms through mid to late evening across
parts of the Midwest into the southeastern Great Plains, while also
continuing with another cluster of storms spreading across northern
portions of the Allegheny Plateau.

...01Z Update...
Mid-level ridging centered near the south Atlantic Seaboard remains
prominent, but is undergoing some suppression as at least a couple
of short wave troughs migrate around its western through northern
periphery. The most substantive of these waves is forecast to
continue migrating northeast of the lower Missouri Valley through Wisconsin/Illinois by late tonight, accompanied by a modest
downstream surface frontal wave. A vigorous jet streak associated
with one or two lower amplitude downstream perturbations is forecast
to propagate from the lee of the lower Great Lakes through southern
New England. It appears that mid/upper troughing with embedded
low-amplitude perturbations will linger across parts of the southern
Great Plains.

Peak afternoon destabilization along the dryline, from near its
frontal intersection (roughly near/north of the Greater Kansas City
area) southwestward into the Texas South Plains, is already waning.
However, it appears that at least a narrow corridor of moderate
residual boundary-layer instability in the warm sector to its east
could may maintain vigorous convection and support continuing
upscale convective growth into mid/late evening across parts of
southeastern Oklahoma, western/northern Arkansas, central/eastern
Missouri and central/northern Illinois. As this occurs, largely
coincident with a northeastward propagating 30-40 kt southwesterly
850 mb jet, this may be accompanied by developing areas of
increasing potential for damaging wind gusts and perhaps a few brief
tornadoes, before convection weakens overnight.

..Kerr.. 04/16/2026

$$

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ACUS01 KWNS 160601
SWODY1
SPC AC 160559

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1259 AM CDT Thu Apr 16 2026

Valid 161200Z - 171200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
ACROSS PARTS OF WESTERN AND CENTRAL NEW YORK INTO SOUTHERN
VERMONT...

...SUMMARY...
A few severe thunderstorms are possible this afternoon in a corridor
across western through central New York (state) and adjacent
southern Vermont.

...Discussion...
A significant mid-level trough and embedded low now digging across
the Pacific Northwest is forecast to split as it continues inland
through this period. One perturbation, perhaps including a
continuing cyclonic circulation, is forecast to turn eastward across
the northern Rockies through the central Canadian/U.S. border area.
Another perturbation is forecast to dig southeastward across the
Great Basin into early Friday. It appears that the larger-scale
evolving troughing will be preceded by a significant cold frontal
surge to the lee of the northern U.S. Rockies, through much of the
northern and central Great Plains by 12Z Friday.

Downstream, initially prominent mid-level ridging centered near the
southern Atlantic Seaboard is forecast to become increasingly
suppressed, as one short wave trough, approaching southwestern
portions of the Great Lakes region early today, turns eastward then southeastward across the lower Great Lakes vicinity into northern
Mid Atlantic. It appears that this will be trailed by another
perturbation, which is forecast to progress east of the Ozark
Plateau through the lower Ohio and Tennessee Valleys, before digging
across the southern Appalachians, downstream of short wave ridging
building across and east of the mid/upper Mississippi Valley.

...Mid South into lower Great Lakes and Northeast...
The primary and trailing short wave troughs advancing to the east of
the Mississippi Valley are forecast to be preceded by the remnants
of overnight convection across parts of the lower Great Lakes, Ohio
Valley, and Mid South at the outset of the period. The impacts of
associated cloud cover and outflow on destabilization within the
warm sector of a broad, but weak, surface low migrating northeast of
the lower Great Lakes during the day remain unclear. However,
various model output, including convection allowing guidance,
suggest that destabilization and strengthening shear along a warm
frontal zone (as it strengthens with differential heating) may
become a focus for organized strong thunderstorm development across
New York state by afternoon. It appears that this may include an
evolving cluster, perhaps preceded by more discrete thunderstorm
activity, in an environment conducive to evolving supercell
structures, with potential to produce severe hail, wind and a risk
for a couple of tornadoes.

Additional thunderstorm activity may eventually develop and
strengthen, accompanied by at least a risk for strong to severe wind
gusts by late afternoon, in a corridor of stronger daytime heating
ahead of a developing cold front spreading into the upper Ohio
Valley/Allegheny and Cumberland Plateau by late afternoon.

There is not a well-defined signal in the latest model output, but a
corridor of differential surface heating along weakening trailing
convective outflow across the Mid South vicinity could become a
focus for supercell development. It currently appears that this
potential could peak across north central into northeastern Arkansas
by late this afternoon, aided by moderate boundary-layer
destabilization and stronger mid-level forcing for ascent associated
with a cyclonic vorticity center migrating across the region.

...Southern Great Plains...
Moderate to strong potential instability is forecast to develop
beneath steep lapse rates, along and east of a dryline which likely
will be retreating westward across the high plains by early this
evening. While this will be conditionally support of severe
thunderstorm development, forcing to support initiation of sustained thunderstorms remains unclear, associated from, perhaps, the higher
terrain near/east of the Texas Big Bend. Beneath moderate to strong southwesterly mid/upper flow, this could include an isolated
supercell or two which could propagate across the Rio Grande River,
before weakening in the presence of increasing inhibition this
evening.

..Kerr/Lyons.. 04/16/2026

$$

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ACUS01 KWNS 161236
SWODY1
SPC AC 161234

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0734 AM CDT Thu Apr 16 2026

Valid 161300Z - 171200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR NEW YORK INTO
SOUTHERN VERMONT AND OVER THE NORTHERN HALF OF ARKANSAS...

...SUMMARY...
Scattered severe thunderstorms are possible this afternoon over New
York into southern Vermont with damaging gusts and perhaps a tornado
or two the primary threats. Large to very large hail is possible
with stronger storms over the northern half of Arkansas.

...Northeast southward into the central Appalachians and Cumberland
Plateau...
Water-vapor imagery this morning shows an upper trough over the
mid/upper MS Valley moving east towards the Northeast. A belt of
strong west-southwesterly 500-mb flow (50-65 kt) will overspread
much of the Northeast today in conjunction with the
eastward-migrating shortwave trough. Visible-satellite imagery
shows scattered to broken cloud cover to the south of a west-east
oriented frontal zone extending east from a surface low analyzed
over Lake Huron. Heating of an adequately moist boundary layer
(surface dewpoints in the 56-62 deg F range) will result in weak to
locally moderate buoyancy by midday into the mid afternoon (500-1250
J/kg MLCAPE). Large-scale ascent associated with the approaching
disturbance and convergence in the vicinity of the frontal zone will
lead to scattered storm development this afternoon. Ample mid to
high-level flow will favor storm organization, including the
possibility for a few supercells and an organized band of storms. A
risk for large hail and a tornado could accompany the more intense
cells, whereas the wind risk will tend to focus with linear
structures that evolve. An isolated threat for wind damage and
perhaps hail will extend southward into PA/WV and the Cumberland
Plateau, where a few stronger storms may yield those hazards.

...Mid South...
Satellite imagery shows the trailing portion of the upper shortwave
trough over the western Great Lakes is moving east across OK this
morning. This upper feature and associated mid-level cold pocket
(-16 to -18 deg C at 500 mb) will move across the MO Ozarks and AR
this afternoon. A reservoir of lower 60s deg F surface dewpoints
and strong heating in wake of early day showers and isolated
thunderstorms will favor robust CAPE profiles and elongated mid to
upper portions of the hodograph. Latest guidance shows several
cells developing within a weakly capped airmass by mid afternoon.
The stronger storms will likely become supercells yielding a risk
for large to very large hail (1 to 3 inches in diameter). Modest
low-level flow will tend to limit low-level mesocyclone intensity
and the lessen the overall tornado risk. A couple of smaller
clusters may evolve during the early evening with an isolated wind
threat potentially ensuing before this activity weakens by mid
evening.

...Edwards Plateau into the TX Big Country and western north TX...
Moderate to strong potential instability is forecast to develop
beneath steep lapse rates, along and east of a dryline. Although
neutral to weak shortwave ridging is expected today, some of the
latest model guidance shows isolated to widely scattered storm
development by late afternoon on the northwestern rim of richer
low-level moisture arcing from the Edwards Plateau into western
north TX. Strong heating will likely erode appreciable remaining
convective inhibition by 20-22 UTC. Strong west-southwesterly
100-kt 200-mb flow will elongate hodographs amidst a moderately
buoyant airmass. Widely spaced/isolated supercells will mainly
yield a large hail threat late this afternoon into the early
evening.

..Smith/Dean.. 04/16/2026

$$

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ACUS01 KWNS 161626
SWODY1
SPC AC 161624

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1124 AM CDT Thu Apr 16 2026

Valid 161630Z - 171200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR NEW YORK INTO
SOUTHERN VERMONT AS WELL AS FOR NORTHERN ARKANSAS...SOUTHERN
MISSOURI AND FAR WESTERN TENNESSEE...

...SUMMARY...
Scattered severe thunderstorms are possible this afternoon over New
York into southern Vermont with damaging gusts and perhaps a tornado
or two the primary threats. Large to very large hail is possible
with stronger storms over the northern half of Arkansas.

...Ozark Plateau into the Mid-South...
Recent visible satellite imagery shows some ACCAS across
south-central MO, indicative of low/mid-level warm advection amid
the steep lapse rate environment in place. These steep lapse rates
are forecast to continue spread eastward, while low-level moisture
advection brings low 60s dewpoints northeastward into the region as
well. This will result in a moderate to strongly buoyant airmass
(i.e. MLCAPE from 1500 to 2000 J/kg) by the early afternoon.
Additionally, moderate mid to high level flow will remain in place,
resulting in long hodographs and overall environmental conditions
that are very favorable for supercells capable of large to very
large hail. Latest guidance continues the earlier trends of
developing storms in this area, which match observational
expectations as well. Large to very large hail (1 to 3 inches in
diameter) is possible with any updrafts that mature into supercells.
Low-level flow is weak, keeping tornado probability low but none
zero. Given the modest pocket of mid-level dry air present,
supercells will likely become outflow dominant with time,
supporting the potential for damaging gusts across the region
(particular eastern areas) as well.

...NY/VT/NH southeastward into the central Appalachians...
Recent surface analysis places a low over the eastern
Ontario/southern Quebec border vicinity, with modest surface
troughing extending southeastward from this low across central Lower
MI. Airmass across much of NY is characterized by dewpoints in the
low 60s. Dewpoints should stay in the low 60s throughout the day
despite modest mixing amid diurnal heating. This should result in
airmass destabilization ahead of the modest surface trough, with a
general increase in large-scale ascent beginning during the
afternoon as well. Little to no convective inhibition is
anticipated, supporting the potential for more cellular development
over the warm sector initially, before a more expansive convective
line develops along the eastward-progressing surface trough. Ample
mid to high-level flow will favor storm organization, including a
risk for large hail and a tornado with the more intense discrete
cells. The wind risk will tend to focus with linear structures that
evolve over time. An isolated threat for wind damage and perhaps
hail will extend southward into PA/WV and the Cumberland Plateau,
where a few stronger storms may yield those hazards.

...Edwards Plateau into the TX Big Country and western north TX...
A strongly buoyant and weakly capped airmass is expected to develop
along the dryline extending southwestward from western OK through
the Edwards Plateau. Although neutral to weak shortwave ridging is
expected throughout much of the morning into the late afternoon,
some limited ascent (associated with a weak shortwave trough moving
out of northern Mexico) may begin to spread across the dryline by
early evening. This combined with dryline circulations may be enough
to initiate isolated to widely scattered thunderstorms. Low-level
flow will be weak, but moderate to strong westerly flow aloft will
result in wind profiles very favorable for supercells capable of
large to very large hail. Any storms that develop should weaken
quickly with the onset of nocturnal cooling.

..Mosier/Squitieri.. 04/16/2026

$$

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ACUS01 KWNS 162002
SWODY1
SPC AC 162000

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0300 PM CDT Thu Apr 16 2026

Valid 162000Z - 171200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS NEW YORK
INTO SOUTHERN VERMONT...AND THE OZARKS INTO THE MID-SOUTH...

...SUMMARY...
Scattered severe thunderstorms are possible this afternoon over New
York into southern Vermont with damaging gusts and perhaps a tornado
or two the primary threats. Very large hail and severe gusts are
possible with the stronger storms over the Ozarks into the
Mid-South.

...20Z Update...
The SLGT in the Ozarks/Mid-South was expanded northward into central
MO, where an isolated supercell with a risk of very large hail and
damaging gusts has emerged along the northern periphery of a remnant
cold pool. Farther south within Severe Thunderstorm Watch 127,
several discrete/splitting supercells continue to pose a risk of
very large hail (recent report of 2.75 inches) and locally damaging
wind gusts. With time, this activity may congeal into a loosely
organized cluster, with an increasing risk of damaging wind gusts.
The MRGL risk was also expanded slightly westward into southwest OK,
where boundary-layer cumulus is gradually deepening. Any isolated
storms that can form here will pose a risk of large to very large
hail and severe downbursts. Finally, the MRGL was expanded slightly
westward in southwest TX toward Fort Stockton. While convective
initiation is still in question here, deepening boundary-layer
cumulus along the higher terrain could result in an isolated storm
or two, with a risk of very large hail.

..Weinman.. 04/16/2026

.PREV DISCUSSION... /ISSUED 1124 AM CDT Thu Apr 16 2026/

...Ozark Plateau into the Mid-South...
Recent visible satellite imagery shows some ACCAS across
south-central MO, indicative of low/mid-level warm advection amid
the steep lapse rate environment in place. These steep lapse rates
are forecast to continue spread eastward, while low-level moisture
advection brings low 60s dewpoints northeastward into the region as
well. This will result in a moderate to strongly buoyant airmass
(i.e. MLCAPE from 1500 to 2000 J/kg) by the early afternoon.
Additionally, moderate mid to high level flow will remain in place,
resulting in long hodographs and overall environmental conditions
that are very favorable for supercells capable of large to very
large hail. Latest guidance continues the earlier trends of
developing storms in this area, which match observational
expectations as well. Large to very large hail (1 to 3 inches in
diameter) is possible with any updrafts that mature into supercells.
Low-level flow is weak, keeping tornado probability low but none
zero. Given the modest pocket of mid-level dry air present,
supercells will likely become outflow dominant with time,
supporting the potential for damaging gusts across the region
(particular eastern areas) as well.

...NY/VT/NH southeastward into the central Appalachians...
Recent surface analysis places a low over the eastern
Ontario/southern Quebec border vicinity, with modest surface
troughing extending southeastward from this low across central Lower
MI. Airmass across much of NY is characterized by dewpoints in the
low 60s. Dewpoints should stay in the low 60s throughout the day
despite modest mixing amid diurnal heating. This should result in
airmass destabilization ahead of the modest surface trough, with a
general increase in large-scale ascent beginning during the
afternoon as well. Little to no convective inhibition is
anticipated, supporting the potential for more cellular development
over the warm sector initially, before a more expansive convective
line develops along the eastward-progressing surface trough. Ample
mid to high-level flow will favor storm organization, including a
risk for large hail and a tornado with the more intense discrete
cells. The wind risk will tend to focus with linear structures that
evolve over time. An isolated threat for wind damage and perhaps
hail will extend southward into PA/WV and the Cumberland Plateau,
where a few stronger storms may yield those hazards.

...Edwards Plateau into the TX Big Country and western north TX...
A strongly buoyant and weakly capped airmass is expected to develop
along the dryline extending southwestward from western OK through
the Edwards Plateau. Although neutral to weak shortwave ridging is
expected throughout much of the morning into the late afternoon,
some limited ascent (associated with a weak shortwave trough moving
out of northern Mexico) may begin to spread across the dryline by
early evening. This combined with dryline circulations may be enough
to initiate isolated to widely scattered thunderstorms. Low-level
flow will be weak, but moderate to strong westerly flow aloft will
result in wind profiles very favorable for supercells capable of
large to very large hail. Any storms that develop should weaken
quickly with the onset of nocturnal cooling.

$$

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ACUS01 KWNS 170101
SWODY1
SPC AC 170059

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0759 PM CDT Thu Apr 16 2026

Valid 170100Z - 171200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS EVENING
ACROSS PARTS OF EASTERN NEW YORK INTO WESTERN NEW ENGLAND...PARTS OF
THE OZARK PLATEAU INTO MID SOUTH...AND THE PECOS VALLEY/RIO GRANDE
VALLEY VICINITY...

...SUMMARY...
Widely scattered areas of scattered strong to severe thunderstorm
development are expected to generally wane through mid to late
evening.

...01Z Update...

...Parts of Upstate New York into western New England...
Forcing for ascent accompanying a weak frontal wave is maintaining
an area of scattered stronger storms now overspreading areas to the
northwest of Albany NY, in the presence of strong deep-layer shear.
Instability sampled in the evening sounding from Albany is rather
weak, but profiles might still be supportive of at least some risk
for localized severe wind and hail into mid/late evening as forcing
overspreads parts of southern Vermont, New Hampshire and adjacent
Maine.

...Ozark Plateau into Mid South...
The primary east-southeastward propagating organized storm cluster
appears to be in the process of weakening, as southeasterly near
surface updraft inflow across middle Tennessee becomes less
unstable. However, renewed thunderstorm development persists along
and to the cool side of the trailing convective outflow across the
Missouri Bootheel vicinity, with additional attempts along a diffuse
zone of differential surface heating extending westward across
northern Arkansas. This is occurring beneath warming and more
strongly capping lower/mid-tropospheric air, but given inflow of
potentially sizable CAPE, in the presence of moderate westerly
shear, there remains at least some risk for supercell development
capable of producing large hail this evening.

...West Texas...
Potential for sustained severe thunderstorm development appears low
along the retreating dryline across parts of northwest Texas into
the South Plains overnight.

..Kerr.. 04/17/2026

$$

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ACUS01 KWNS 170602
SWODY1
SPC AC 170600

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0100 AM CDT Fri Apr 17 2026

Valid 171200Z - 181200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
INTO TONIGHT ACROSS PARTS CENTRAL AND SOUTHWESTERN WISCONSIN...FAR
SOUTHEASTERN MINNESOTA...EASTERN IOWA...MUCH OF NORTHERN AND CENTRAL
ILLINOIS...NORTHERN AND CENTRAL MISSOURI...EASTERN AND SOUTHERN
KANSAS...AND NORTHERN OKLAHOMA...

...SUMMARY...
Widespread strong to severe thunderstorm development appears
possible today into tonight across parts of the Upper Midwest
southward across the lower Missouri Valley into central Great
Plains. Initially this may be accompanied by a risk for large hail
and a few strong tornadoes, before damaging wind gusts become the
most prominent hazard by this evening.

...Discussion...
A couple of notable short wave perturbations have emerged from
splitting larger-scale mid-level troughing now overspreading the
northern Rockies and Great Basin. One, including a remnant embedded
cyclonic circulation, is beginning to accelerate east-northeastward
into and across the central Canadian/U.S. border vicinity. The
other is still digging into the eastern Great Basin, but forecast to
turn across the Wyoming/Colorado Rockies during the day, before
shearing northeastward toward the Upper Midwest. It appears that
this will be preceded by several lower amplitude impulses already
emanating from the subtropical eastern Pacific.

In lower-levels, a significant cold front is already surging
southward to the lee of the northern Rockies and forecast to advance
across much of the remainder of the northern Great Plains by 12Z
this morning. Models indicate that significant cyclogenesis may
subsequently ensue northwest/north of Lake Superior toward James Bay
later today through tonight. At the same time, it appears that a
secondary frontal wave will migrate northeast of the mid Missouri
Valley through the Upper Midwest/Great Lakes vicinity. Another lee
cyclone may attempt to form near/north of the Texas/Oklahoma
Panhandle vicinity, but probably will be overtaken by the southward
surging cold front before migrating out of the high plains.

The northward advection of relatively moist low-level air is ongoing
from the southern into central Great Plains and lower Missouri
Valley, and forecast to continue spreading northward within a
pre-cold frontal plume through portions of the Upper Midwest/Great
Lakes region by this afternoon. Beneath steep lapse rates, this may
contribute to sizable mixed-layer CAPE within a corridor from the
east central Great Plains through the mid/upper Mississippi Valley
by this afternoon.

There is notable spread among the various model output concerning
most of these developments, which may have a significant impact on
the convective evolution and associated severe weather potential
today through tonight. However, potential exists for widespread
convective development capable of producing damaging surface gusts,
large hail and a couple of strong tornadoes.

...Upper Mississippi Valley/Midwest vicinity...
It appears that a corridor of stronger surface pressure falls may
shift from western Iowa north-northeastward through western
Wisconsin by early this afternoon, accompanied by substantive
boundary-layer destabilization and strengthening southerly low-level
wind fields with enlarging hodographs. Based on the latest model
output, including convection allowing guidance, it appears that this
may contribute to a window of opportunity for discrete supercell
development within an environment potentially conducive to strong
tornadoes, before activity grows upscale and eventually outpaces the northeastward boundary-layer destabilization.

...Central Great Plains through middle Mississippi Valley/Midwest...

Uncertainty lingers concerning how quickly the surface cold front
will tend to undercut a developing corridor of stronger pre-frontal
surface heating and destabilization, particularly across the central
into southern Great Plains. However, by early this afternoon, this
corridor appears likely to develop along an axis from south central
Kansas toward northwestern Missouri, providing a focus for rapidly
developing storms including supercells. Initially this may include
hail exceeding 2 inches in diameter, and potential for a few
tornadoes before convection grows upscale, spreads east of the axis
of maximum instability and also become undercut by the front.

Perhaps aided by forcing associated with one of the perturbations
emerging from lower latitudes, there appears a signal in model
output that the upscale growing convection may eventually become
better organized with one or two notable mesoscale convective
vortices evolving while spreading ahead of the front across and
northeast of the lower Missouri Valley late this afternoon and
evening. Downward mixing of strengthening rear-inflow, within a
sheared ambient southwesterly deep-layer mean flow already on the
order of 35-40 kt, widespread strong to severe wind gusts appear
possible, with strongest gusts and/or perhaps brief tornadoes
accompanying evolving mesovortices along the gust front.

The cold front/dryline intersection may become another focus for
discrete supercell development across parts of south central Kansas
into adjacent northwestern Oklahoma by late afternoon. However, the
extent of the associated severe weather potential will depend on how
quickly this activity is overtaken by the cold front.

..Kerr/Lyons.. 04/17/2026

$$

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ACUS01 KWNS 171240
SWODY1
SPC AC 171239

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0739 AM CDT Fri Apr 17 2026

Valid 171300Z - 181200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM PARTS OF
THE UPPER AND MID MISSISSIPPI VALLEY SOUTHWESTWARD INTO KANSAS AND
OKLAHOMA...

...SUMMARY...
Numerous severe thunderstorms are likely this afternoon into tonight
across parts of the Upper Midwest southward across the lower
Missouri Valley into central Great Plains. Initially this may be
accompanied by a risk for large to giant hail and a few strong
tornadoes, before severe wind gusts 60 to 90 mph become the
most prominent hazard by this evening.

...Synopsis...
Surface analysis this morning depicts a front bisecting MN north to
south to a low near the NE-IA-SD border, with the front extending
southwestward into the central High Plains. Water-vapor imagery
shows a prominent upper trough near the MT-ND border
south-southwestward into eastern UT. A belt of increasingly strong southwesterly 500-mb flow will overspread a destabilizing warm
sector today as the upper trough eventually reaches the Upper
Midwest and central Great Plains late tonight. Concurrently, the aforementioned cyclone will develop northeast to Lake Superior as a
warm front over IA advances northward into the western Great Lakes.
Meanwhile, the cold front will sweep southeast reaching the central
Great Lakes southwestward into the southern Great Plains by early
Saturday.

...Upper and Mid Mississippi Valley...
A northward expanding warm/moist sector on the nose of a 50+ kt
southerly LLJ will continue to destabilize as large-scale ascent
approaches from the west. A large-hail threat may develop this
morning with developing convection across southern MN (see
forthcoming MCD #472 for short-term details). Heating and advection
of 60s deg F surface dewpoints beneath steep mid-level lapse rates
will support the development of a moderately to very unstable
airmass from IA-IL northward into the upper MS Valley to the east of
the front and southeast of the low. Upwards of 1500-3000 J/kg
MLCAPE is forecast immediately ahead of the front with strengthening
flow aloft, strongly favoring organized storms, including
supercells. Recent model guidance continues to show the development
of discrete supercells later this afternoon ahead of the front over
parts of central/northern WI near the low, and farther south in the
vicinity of eastern IA into adjacent portions of WI/northwest IL.
All hazards will be possible with this potential activity, including
the possibility for an intense tornado. Large to giant hail will be
possible with supercells. Other storms likely to evolve quickly
into a band of severe thunderstorms will develop farther west and
push east coincident with the front. Damaging wind gusts will tend
to become more prevalent during the evening with linear storm modes.
Some tornado risk may continue into the evening as maturing bands of
storms yield a threat for bowing segments and embedded mesovortices,
before this activity gradually diminishes late as it moves east into
IN/Lower MI late.

...KS-OK eastward into the lower MO Valley...
Continued moistening and heating of an airmass to the east of a
dryline/cold front and associated triple point will lead to a very
unstable airmass from OK into KS by early to mid afternoon. A
capping inversion will likely inhibit storm development until mid
afternoon near the front. Initial storm development will likely be supercellular near the triple point before a more extensive band of
cellular storms develops along the boundary. Both a supercell and
QLCS tornado risk is apparent given the appreciably large
CAPE/shear. A coalescing of cold pools and intensification of a
squall line with embedded surges and bowing segments may result in
focused swaths of more intense severe gusts (i.e., locally 75-90
mph) from south-central and eastern KS into west-central MO.
Farther south, a more conditional setup south of the triple point
along the dryline is expected. Large to giant hail could accompany
any mature/sustained supercell along with a tornado risk.
Eventually the front will sweep southeastward with a convective line
yielding a risk for wind/hail.

..Smith/Dean.. 04/17/2026

$$

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ACUS01 KWNS 171637
SWODY1
SPC AC 171635

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1135 AM CDT Fri Apr 17 2026

Valid 171630Z - 181200Z

...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS FROM FAR
NORTHWEST OKLAHOMA THROUGH CENTRAL AND EASTERN KANSAS INTO
WEST-CENTRAL MISSOURI...

...SUMMARY...
Numerous severe thunderstorms are likely this afternoon into tonight
across parts of the Upper Midwest southward across the lower
Missouri Valley and central/southern Great Plains. Initially this
may be accompanied by a risk for large to giant hail and a few
strong tornadoes, before severe wind gusts of 60 to 90 mph become
the most prominent hazard by this evening.

...Synopsis...
Recent surface analysis places a low over south-central MN, with a
cold front extending southwestward to another low over central KS. A
warm front also extends southwestward from the MN low through far
southwest MN and far northern IL into central IN. This warm front is
demarcated well by the 56 deg F isodrosotherm. Farther south, a
dryline extends from the triple point KS low back southwestward
through the TX Panhandle and into far southeast NM. A broad, moist
warm sector exists to the east of the cold front and dryline,
characterized largely by dewpoints in the low to mid 60s.

A well-defined shortwave trough is apparent on satellite imagery,
extending from southern Saskatchewan back southwestward into the
eastern Great Basin. This wave is forecast to continue eastward,
with a attendant increase in the mid-level flow across much of the
Plains and Upper/Mid MS Valley. The cold front will surge eastward/southeastward in response to this wave as well, interacting
with the warm sector to support numerous strong to severe
thunderstorms from parts of the Upper Midwest southward across the
lower Missouri Valley into southern Plains.

...Upper/Mid MS Valley...
Moderate to strong low-level moisture advection is expected across
the Upper MS Valley today as the surface low mentioned in the
synopsis progresses northeastward, with an attendant northward shift
of the warm front as well. The risk across this region may evolve in
several phases, beginning with the elevated thunderstorms currently
ongoing across northwest WI. This storms will likely continue
northeastward, posing a risk for severe hail and isolated damaging
gusts. Additional development is possible northwest of this activity
along the occluded front, with some hail possible here as well.

Farther south, the northeastward advecting low-level moisture
coupled with strong heating and steep lapse rates will result in a
strongly unstable airmass along and just south of the warm front by
the early afternoon. Storm initiation is anticipated within this
open warm sector by early afternoon, forced by a mix of warm-air
advection, low-level confluence, and subtly increasing large-scale
ascent. This activity should be ahead of the front and initially
discrete. The overall parameter space will be characterized by
strong to very strong buoyancy, moderate deep-layer vertical shear,
and strong low-level helicity. Supercells capable of all hazards are
expected, including large to very large (i.e. 3"+ hail), strong to
intense tornadoes, and severe wind gusts. Storm interactions are
expected to strongly influence the tornado risk, with the initially
discrete mode likely becoming messy quickly.

Farther west, other storms are likely to evolve quickly along the
front, developing into a band of severe thunderstorms that will push
east coincident with the front. Damaging wind gusts will tend to
become more prevalent during the evening with linear storm modes.
Some tornado risk may continue into the evening as maturing bands of
storms yield a threat for bowing segments and embedded mesovortices,
before this activity gradually diminishes late as it moves east into
IN/Lower MI late.

...KS/OK/MO...
A very unstable airmass is expected to develop along and ahead of
the triple point over south-central KS an associated cold front and
dryline. Strong low-level convergence will likely lead to initial
storm development near the triple point. This initial activity will
be supercellular and capable of very large to giant hail (over
3-3.5" in diameter). Highest coverage of very large hail is expected
over from far northwest OK into south-central KS. Strong downdrafts
(60 to 80 mph) are possible as well. With a largely
boundary-parallel orientation to the deep-layer shear, the tornado
risk appears relatively lower. However, given the supercell mode and
potential interactions with outflow, a low-probability tornado risk
remains. A more north-south configuration to the dryline supports a
conditional tornado risk into far northwest TX.

With time, upscale growth and the development of a
forward-propagating MCS is anticipated across central and eastern
KS. Very strong gusts (80+ mph) are possible with this MCS.
Additionally, some QLCS tornado risk will exist within this line as
long as it stays ahead of the surging cold front. The front will
continue sweeping southeastward, with storms along this boundary
yielding a risk for wind/hail.

..Mosier/Chalmers.. 04/17/2026

$$

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ACUS01 KWNS 171955
SWODY1
SPC AC 171953

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0253 PM CDT Fri Apr 17 2026

Valid 172000Z - 181200Z

...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS FROM FAR
NORTHWEST OKLAHOMA THROUGH CENTRAL AND EASTERN KANSAS INTO
WEST-CENTRAL MISSOURI...

...SUMMARY...
Numerous severe thunderstorms are likely this afternoon into tonight
across parts of the Upper Midwest southward across the lower
Missouri Valley and central/southern Great Plains. Initially this
may be accompanied by a risk for large to giant hail and a few
strong tornadoes, before severe wind gusts of 60 to 90 mph become
the most prominent hazard by this evening.

...20Z Update...
Severe probabilities have been adjusted to account for progression
of the cold front this afternoon. The remainder of the forecast is
unchanged. See MD 475 for short-term details of evolving tornado
risk along the Illinois/Wisconsin border.

..Wendt.. 04/17/2026

.PREV DISCUSSION... /ISSUED 1203 PM CDT Fri Apr 17 2026/

...Synopsis...
Recent surface analysis places a low over south-central MN, with a
cold front extending southwestward to another low over central KS. A
warm front also extends southwestward from the MN low through far
southwest MN and far northern IL into central IN. This warm front is
demarcated well by the 56 deg F isodrosotherm. Farther south, a
dryline extends from the triple point KS low back southwestward
through the TX Panhandle and into far southeast NM. A broad, moist
warm sector exists to the east of the cold front and dryline,
characterized largely by dewpoints in the low to mid 60s.

A well-defined shortwave trough is apparent on satellite imagery,
extending from southern Saskatchewan back southwestward into the
eastern Great Basin. This wave is forecast to continue eastward,
with a attendant increase in the mid-level flow across much of the
Plains and Upper/Mid MS Valley. The cold front will surge eastward/southeastward in response to this wave as well, interacting
with the warm sector to support numerous strong to severe
thunderstorms from parts of the Upper Midwest southward across the
lower Missouri Valley into southern Plains.

...Upper/Mid MS Valley...
Moderate to strong low-level moisture advection is expected across
the Upper MS Valley today as the surface low mentioned in the
synopsis progresses northeastward, with an attendant northward shift
of the warm front as well. The risk across this region may evolve in
several phases, beginning with the elevated thunderstorms currently
ongoing across northwest WI. This storms will likely continue
northeastward, posing a risk for severe hail and isolated damaging
gusts. Additional development is possible northwest of this activity
along the occluded front, with some hail possible here as well.

Farther south, the northeastward advecting low-level moisture
coupled with strong heating and steep lapse rates will result in a
strongly unstable airmass along and just south of the warm front by
the early afternoon. Storm initiation is anticipated within this
open warm sector by early afternoon, forced by a mix of warm-air
advection, low-level confluence, and subtly increasing large-scale
ascent. This activity should be ahead of the front and initially
discrete. The overall parameter space will be characterized by
strong to very strong buoyancy, moderate deep-layer vertical shear,
and strong low-level helicity. Supercells capable of all hazards are
expected, including large to very large (i.e. 3"+ hail), strong to
intense tornadoes, and severe wind gusts. Storm interactions are
expected to strongly influence the tornado risk, with the initially
discrete mode likely becoming messy quickly.

Farther west, other storms are likely to evolve quickly along the
front, developing into a band of severe thunderstorms that will push
east coincident with the front. Damaging wind gusts will tend to
become more prevalent during the evening with linear storm modes.
Some tornado risk may continue into the evening as maturing bands of
storms yield a threat for bowing segments and embedded mesovortices,
before this activity gradually diminishes late as it moves east into
IN/Lower MI late.

...KS/OK/MO...
A very unstable airmass is expected to develop along and ahead of
the triple point over south-central KS an associated cold front and
dryline. Strong low-level convergence will likely lead to initial
storm development near the triple point. This initial activity will
be supercellular and capable of very large to giant hail (over
3-3.5" in diameter). Highest coverage of very large hail is expected
over from far northwest OK into south-central KS. Strong downdrafts
(60 to 80 mph) are possible as well. With a largely
boundary-parallel orientation to the deep-layer shear, the tornado
risk appears relatively lower. However, given the supercell mode and
potential interactions with outflow, a low-probability tornado risk
remains. A more north-south configuration to the dryline supports a
conditional tornado risk into far northwest TX.

With time, upscale growth and the development of a
forward-propagating MCS is anticipated across central and eastern
KS. Very strong gusts (80+ mph) are possible with this MCS.
Additionally, some QLCS tornado risk will exist within this line as
long as it stays ahead of the surging cold front. The front will
continue sweeping southeastward, with storms along this boundary
yielding a risk for wind/hail.

$$

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ACUS01 KWNS 180101
SWODY1
SPC AC 180059

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0759 PM CDT Fri Apr 17 2026

Valid 180100Z - 181200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER MUCH OF
ILLINOIS INTO NORTHEAST MISSOURI...AND OVER NORTHERN OKLAHOMA...

...SUMMARY...
Damaging storms producing wind, hail and isolated tornadoes remain
possible this evening from Illinois into Oklahoma.

...WI/MI into IL and MO...
Supercells have largely merged into a broken line of assorted bows
from far southeast WI across much of northern into western IL and
trailing into northeast MO. The 00Z ILX sounding shows steep lapse
rates aloft and large deep-layer shear, as well as veering winds
with height. Low-level SRH will remain favorable for rotation to
develop at least briefly anywhere within the line, with damaging
winds the most likely threat. Storms have recently become better
organized over central MO, and this activity may affect the St.
Louis area later tonight. For lower MI into northern IN, the
organized line of storms to the west along with a 60 kt low-level
jet suggest at least isolated severe gusts may occur overnight
despite lesser instability.

For more information about Illinois, see mesoscale discussion 484.

...OK...Southeast KS...southwest MO...northwest AR...
Scattered severe cells persist near and north of the cold front
across much of northern OK and extending into southeast KS. Although
the undercutting cold air will likely mitigate wind potential, steep
lapse rates aloft along with ample deep-layer shear will continue to
favor hail. Storm coverage may be more isolated into southwest OK
later tonight, but the environment remains quite favorable for large
hail.

One corridor for possible damaging wind or even a tornado is over
northeast OK into southwest MO. Here, the front is not surging as
fast, and storms over Osage county are already oriented more
favorably N-S relative to the deep-layer shear. A southwest
low-level jet near 50 kt will further support low-level rotation.

..Jewell.. 04/18/2026

$$

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ACUS01 KWNS 180454
SWODY1
SPC AC 180453

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1153 PM CDT Fri Apr 17 2026

Valid 181200Z - 191200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE
UPPER OHIO VALLEY TO THE APPALACHIANS...

...SUMMARY...
Scattered strong to severe thunderstorms capable of damaging winds
and hail will be possible on Saturday across the upper Ohio Valley
and central Appalachians. Isolated severe hail is also possible
across parts of central Texas.

...Synopsis...
A large upper trough with elongated leading speed max will sweep
across the Great Lakes and OH Valley during the day and into the
Appalachians by Sunday morning. Meanwhile, moderate westerlies aloft
will persist across TX with the aid of a subtropical jet.

At the surface, a cold front will move across OH and KY through
early afternoon, and into western NY, PA, and WV late in the day.
This front will also extend far southwestward toward the
northwestern Gulf Coast and into far southern TX. Ahead of the
front, a narrow plume of 50s to lower 60s F dewpoints will exist as
far north as OH and PA, with more robust moisture into TX with upper
60s F dewpoints.

...Upper Ohio Valley/Appalachians...
A remnant line of showers and thunderstorms is expected to persist
near the cold front this morning as it moves across the OH Valley
and toward the lower Great Lakes. Daytime heating will help
destabilize the air mass ahead of this activity, and storm
rejuvenation is expected after 18Z from near Lake Erie into eastern
KY. These storms will mature in the 21-00Z timeframe, affecting
eastern OH, WV, and into PA and possibly southwest NY.

Substantial southwest flow aloft will help to push these storms
quickly east/northeast across the region, and deep-layer shear may
favor scattered cells initially. Marginal hail will be possible,
along with locally strong gusts, especially as storm mode becomes
linear and peak heating has been achieved. Given the narrow
instability axis, storms should wane after sunset.

...South-Central Texas...
Scattered showers and elevated thunderstorms are expected throughout
much of the day as the cold front rapidly undercuts a moist and
unstable air mass. Forecast soundings show MUCAPE parcels rooted in
the 850-700 mb layer, with effective deep-layer shear of 50-60 kt.
Initial activity may develop over central TX during the morning and
through midday, with additional new elevated development translating
southward as the front continually lifts the moist air mass. A few
hail reports at or above 1.00" will be possible.

..Jewell/Moore.. 04/18/2026

$$

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ACUS01 KWNS 181233
SWODY1
SPC AC 181232

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0732 AM CDT Sat Apr 18 2026

Valid 181300Z - 191200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF THE
UPPER OHIO VALLEY TO THE APPALACHIANS...

...SUMMARY...
Scattered strong to severe thunderstorms capable mainly of damaging
winds will be possible today across the upper Ohio Valley and
central Appalachians.

...Synopsis...
Water-vapor imagery this morning shows a large-scale upper trough
over the Upper Midwest into the south-central Plains. An elongated
mid-level vorticity lobe and associated speed max will quickly move
eastward across the Midwest today and reach the Lower Great Lakes
and upper OH Valley late tonight. Farther south, a belt of strong west-southwesterly flow associated with a subtropical jet will
reside over TX.

A cold front extending from a low near James Bay southward through
the Great Lakes and into TX will continue to push east and southeast
through the period. Convective outflow over the OH Valley to the
east of the front will eventually be overtaken by the front later
today as a band of showers/thunderstorms develops over the upper OH
Valley by early afternoon.

...OH Valley into the Appalachians...
Some heating combined with a gradually moistening airmass (55-60 deg
F surface dewpoints) will result in weak destabilization by midday
as convective development ensues near the preceding outflow/wind
shift and front. Ample mid to high-level flow will aid in some
potential for storm organization, mainly in the form of a few
stronger cells and linear bands. Widely scattered strong to severe
gusts capable of wind damage will likely be the primary hazard, but
an isolated risk for hail or a brief tornado is possible with the
strongest cells. This activity will likely weaken by early evening
as it encounters a slightly drier and less unstable airmass with
east extent.

...Central Texas...
Scattered showers and elevated thunderstorms are expected throughout
much of the day as the cold front rapidly undercuts a moist and
unstable air mass. The 12 UTC Del Rio, TX raob shows an 8.2 deg
C/km 700-500 mb lapse rate. Forecast soundings show MUCAPE parcels
rooted in the 850-700 mb layer, with effective deep-layer shear of
50-60 kt. Although an isolated risk for large hail appears to be
the main hazard with the stronger cells, there has been some
indication that a localized risk for severe gusts could accompany
the strongest cores. For short-term details regarding a risk for
hail/wind with a few stronger thunderstorms this morning extending
from the Concho Valley east-northeast towards DFW, reference MCD
#490.

..Smith/Dean.. 04/18/2026

$$

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ACUS01 KWNS 181605
SWODY1
SPC AC 181603

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1103 AM CDT Sat Apr 18 2026

Valid 181630Z - 191200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
ACROSS PARTS OF THE UPPER OHIO VALLEY AND LOWER GREAT LAKES
REGION....

...SUMMARY...
Widely scattered strong to severe thunderstorms capable mainly of
damaging winds will be possible today across the Upper Ohio Valley
and Lower Great Lakes.

...Upper OH Valley...
Latest surface analysis shows a cold front pushing eastward across
western OH, associated with a band of widespread clouds and light precipitation. Mostly clear skies are present ahead of the front,
where temperatures are warming through the 70s. This will lead to a
corridor of marginal afternoon instability and the potential for
scattered thunderstorm intensification along the front. Forecast
soundings show strong mid-level winds and steep low-level lapse
rates, supportive of strong downdrafts in any vigorous convection.
However, CAM guidance is consistent in showing very few
organized/strong storms through the day. Will maintain the SLGT
risk for the conditional risk of a few damaging wind events, but
with limited confidence.

...TX...
Isolated intense thunderstorms have been ongoing this morning in the post-frontal regime across central TX. These storms have produced
hail and gusty winds for several hours. It appears likely that this
scenario will shift eastward and weaken early this afternoon as the
primary upper jet moves into AR and away from the region, but will
maintain the MRGL risk area for a few more hours and extend it into
parts of AR/LA.

..Hart/Chalmers.. 04/18/2026

$$

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ACUS01 KWNS 182006
SWODY1
SPC AC 182005

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0305 PM CDT Sat Apr 18 2026

Valid 182000Z - 191200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS WITHIN THE
CENTRAL APPALACHIANS INTO THE UPPER OHIO VALLEY VICINITY...AND PARTS
OF CENTRAL TEXAS...

...SUMMARY...
Isolated marginally severe hail is possible in portions of central
Texas. Isolated damaging winds remain possible from the central
Appalachians into the Upper Ohio Valley vicinity.

...20Z Update...
Based on observational trends 15% wind probabilities were removed
from the Upper Ohio Valley vicinity. Wind gusts along with weak,
shallow convection (with little lightning) have generally been in
the 30 kt range with isolated cases of low 40 kt gusts. Isolated
wind damage remains possible, but a more organized threat is not
expected given weak buoyancy downstream. Elsewhere, marginally
severe hail remains possible with isolated, elevated convection in
central Texas.

..Wendt.. 04/18/2026

.PREV DISCUSSION... /ISSUED 1103 AM CDT Sat Apr 18 2026/

...Upper OH Valley...
Latest surface analysis shows a cold front pushing eastward across
western OH, associated with a band of widespread clouds and light precipitation. Mostly clear skies are present ahead of the front,
where temperatures are warming through the 70s. This will lead to a
corridor of marginal afternoon instability and the potential for
scattered thunderstorm intensification along the front. Forecast
soundings show strong mid-level winds and steep low-level lapse
rates, supportive of strong downdrafts in any vigorous convection.
However, CAM guidance is consistent in showing very few
organized/strong storms through the day. Will maintain the SLGT
risk for the conditional risk of a few damaging wind events, but
with limited confidence.

...TX...
Isolated intense thunderstorms have been ongoing this morning in the post-frontal regime across central TX. These storms have produced
hail and gusty winds for several hours. It appears likely that this
scenario will shift eastward and weaken early this afternoon as the
primary upper jet moves into AR and away from the region, but will
maintain the MRGL risk area for a few more hours and extend it into
parts of AR/LA.

$$

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ACUS01 KWNS 190023
SWODY1
SPC AC 190022

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0722 PM CDT Sat Apr 18 2026

Valid 190100Z - 191200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe storms are unlikely through tonight.

...Synopsis...
Little thunderstorm activity is currently present near the cold
front moving across NY and PA, with only isolated lightning flashes
across WV into western VA. Given the loss of heating, and already
minimal instability present, severe storms appear unlikely to
develop.

Farther south, scattered storms exist over northern AL near the
front, and north of the boundary from LA into central TX. In both
these areas, instability is weak, and generally should not support a
severe threat as the surface air mass cools.

..Jewell.. 04/19/2026

$$

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ACUS01 KWNS 190519
SWODY1
SPC AC 190517

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1217 AM CDT Sun Apr 19 2026

Valid 191200Z - 201200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe thunderstorms are not forecast today.

...Synopsis...
A large upper trough extending from the Great Lakes into the OH and
TN Valleys will move into the northeastern US today, with a weak
upper ridge across the Rockies. This pattern will favor high
pressure over the central and eastern states, stable conditions and
minimal thunderstorm activity. A cold front associated the eastern
trough will be well off the East Coast by midday, with drying
offshore flow. Minimal instability may yield isolated thunderstorms
over eastern Florida, or perhaps across the Rio Grande Valley where
elevated moisture and weak instability will remain atop the surface
cool layer. In any case, severe storms are not forecast.

..Jewell/Moore.. 04/19/2026

$$

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ACUS01 KWNS 191244
SWODY1
SPC AC 191243

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0743 AM CDT Sun Apr 19 2026

Valid 191300Z - 201200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe thunderstorms are not forecast today.

...Synopsis...
Water-vapor imagery this morning shows a large-scale upper trough
from James Bay southward through the Great Lakes and TN Valley. The
upper trough will continue to move east and reach the Lower Great
Lakes and East Coast by daybreak Monday. In the low levels, a cold
front will push east of the Carolina coast by early afternoon.
Surface high pressure will influence conditions across the central
and eastern states in wake of the cold front. Weak instability will
yield isolated thunderstorms over parts of the south Florida,
eastern North Carolina, and weak elevated storms over south Texas.

..Smith/Thompson.. 04/19/2026

$$

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ACUS01 KWNS 191601
SWODY1
SPC AC 191559

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1059 AM CDT Sun Apr 19 2026

Valid 191630Z - 201200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe thunderstorms are not forecast today.

...Synopsis...
A shortwave trough currently approaching Baja California will
provide increasing large-scale forcing for ascent over Mexico and
south/west TX today. This will lead to scattered thunderstorms
through the period.

Other isolated afternoon thunderstorms are expected ahead of a
frontal band affecting New England and eastern NC, beneath cold air
aloft in the Lower Great Lakes region, and over south FL. In all of
these areas, weak instability and/or limited vertical shear will
preclude a risk of organized severe storms.

..Hart/Bunting.. 04/19/2026

$$

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ACUS01 KWNS 191957
SWODY1
SPC AC 191955

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0255 PM CDT Sun Apr 19 2026

Valid 192000Z - 201200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe thunderstorms are not forecast today.

...20Z Update...
The TSTM area was removed in eastern NC, where the cold front and
related thunderstorm potential has shifted offshore. The TSTM area
was also trimmed behind a band of eastward-moving thunderstorms
departing the New England coast, and no lightning is expected behind
this activity. Farther south in parts of central FL, isolated
thunderstorms are evolving along the sea breeze focused over the
Treasure Coast. While storm coverage and intensity are expected to
remain isolated/marginal, a warm/unstable PBL and around 35 kt of
midlevel flow could support a strong storm or two capable of locally
strong gusts, though this activity is expected to remain sub-severe.

..Weinman.. 04/19/2026

.PREV DISCUSSION... /ISSUED 1059 AM CDT Sun Apr 19 2026/

...Synopsis...
A shortwave trough currently approaching Baja California will
provide increasing large-scale forcing for ascent over Mexico and
south/west TX today. This will lead to scattered thunderstorms
through the period.

Other isolated afternoon thunderstorms are expected ahead of a
frontal band affecting New England and eastern NC, beneath cold air
aloft in the Lower Great Lakes region, and over south FL. In all of
these areas, weak instability and/or limited vertical shear will
preclude a risk of organized severe storms.

$$

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ACUS01 KWNS 200006
SWODY1
SPC AC 200004

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0704 PM CDT Sun Apr 19 2026

Valid 200100Z - 201200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe thunderstorms are not forecast.

...Synopsis...
Scattered thunderstorms currently exist along a cold front mainly
over the western Atlantic Ocean, and earlier affected Downeast
Maine. Thunderstorms chances have ended there as the front has now
pushed through the area.

To the west, broken arc of elevated thunderstorms extends from near
El Paso southeastward across the Rio Grande Valley. This area is in
a zone of theta-e advection just off the surface, with unstable
parcels rooted in the 850-700 mb layer. Weak instability will
preclude much of a hail risk, but overall storm chances should
continue to increase into central TX tonight.

..Jewell.. 04/20/2026

$$

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ACUS01 KWNS 200420
SWODY1
SPC AC 200418

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1118 PM CDT Sun Apr 19 2026

Valid 201200Z - 211200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe storms are not expected today.

...Synopsis...
An upper trough will exit the northeastern states today, with
northwest flow aloft extending from the northern Plains to the East
Coast. Upper ridging will occur over the Rockies, while a large
upper trough slowly approaches the West Coast.

At the surface, high pressure will result in relatively stable
conditions for much of the central and eastern CONUS, with centers
over the Mid Atlantic and near the northern Gulf Coast.

In the wake of the eastern trough, winds just off the surface will
maintain a zone of elevated moisture and instability over much of
TX, where scattered showers and storms will be most likely. Weak
instability will preclude any severe storm chances there.

To the west, cooling aloft with the approaching upper trough will
support weak instability into parts of OR and WA, with isolated late
day thunderstorms possible over portions of the Cascades.
Small/non-severe hail cannot be ruled out, along with locally gusty
winds mainly in the 00-03Z time frame.

..Jewell/Chalmers.. 04/20/2026

$$

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ACUS01 KWNS 201220
SWODY1
SPC AC 201218

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0718 AM CDT Mon Apr 20 2026

Valid 201300Z - 211200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe storms are not expected today.

...Synopsis...
Water-vapor imagery this morning shows a weak upper trough centered
over AZ and Sonora moving east undercutting a ridge over the
Rockies. This upper feature will move into the southern High Plains
by late tonight. Farther west, a mid- to upper-level low will move
slowly east from the eastern Pacific toward the CA/OR coast.

Scattered showers and weak elevated storms will be possible across a
large portion of TX today. Farther west, isolated to scattered
thunderstorms are possible in association with the weak upper trough
over parts of the Desert Southwest. Primarily diurnal storm
activity over the southern FL Peninsula is expected, as well as
isolated late day thunderstorms over portions of the Cascades.

Elsewhere, surface high pressure will lead to tranquil conditions
across much of the CONUS precluding storm development.

..Smith/Thompson.. 04/20/2026

$$

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ACUS01 KWNS 201554
SWODY1
SPC AC 201552

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1052 AM CDT Mon Apr 20 2026

Valid 201630Z - 211200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe storms are not expected today.

...Synopsis...
An upper impulse will continue to pose a risk of scattered
thunderstorms over parts of NM and south/west TX through the
afternoon, with activity spreading into north-central TX late
tonight.

Other thunderstorms are possible this afternoon and evening over
south FL in a moist and marginally unstable air mass, along the
coast of southern New England, and over portions of OR/WA. In all
areas, weak instability will preclude the risk of organized severe
storms.

..Hart/Flournoy.. 04/20/2026

$$

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ACUS01 KWNS 201947
SWODY1
SPC AC 201946

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0246 PM CDT Mon Apr 20 2026

Valid 202000Z - 211200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe storms are not expected today.

...20Z Update...
The TSTM area over the coast of southern New England and the
Mid-Atlantic was removed, as large-scale forcing for ascent and
related thunderstorm activity has shifted offshore. Elsewhere, the
previous forecast remains on track.

..Weinman.. 04/20/2026

.PREV DISCUSSION... /ISSUED 1052 AM CDT Mon Apr 20 2026/

...Synopsis...
An upper impulse will continue to pose a risk of scattered
thunderstorms over parts of NM and south/west TX through the
afternoon, with activity spreading into north-central TX late
tonight.

Other thunderstorms are possible this afternoon and evening over
south FL in a moist and marginally unstable air mass, along the
coast of southern New England, and over portions of OR/WA. In all
areas, weak instability will preclude the risk of organized severe
storms.

$$

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ACUS01 KWNS 210058
SWODY1
SPC AC 210057

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0757 PM CDT Mon Apr 20 2026

Valid 210100Z - 211200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe storms are not expected through tonight.

...Discussion...
Scattered thunderstorms persist across central and southern TX this
evening, where southerly 850 mb winds are aiding lift/warm advection
atop the relatively cool boundary layer. In addition, a weak wave
aloft is moving across the southern Plains. As such, storms may
increase in coverage through tonight, expanding into northern and
eastern TX. Effective shear will remain weak especially over
northern areas, and severe storms are not expected.

Elsewhere, showers will generally decrease over far southern FL with
the loss of heating. Farther west, an isolated lightning flash
cannot be ruled out over parts of the WA/OR Cascades as an offshore
upper trough slowly pushes east.

..Jewell.. 04/21/2026

$$

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ACUS01 KWNS 210538
SWODY1
SPC AC 210537

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1237 AM CDT Tue Apr 21 2026

Valid 211200Z - 221200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Thunderstorms are expected today over much of Texas, from Illinois
into Ohio, and over portions of central California. Severe weather
is not currently forecast.

...Synopsis...
An upper ridge will move into the Plains as an upper trough moves
inland over the West, with a strong cyclonic speed max moving across
CA and into the Great Basin. Meanwhile, northwest flow aloft will
extend from the Great Lakes into the Mid Atlantic. Farther south, a
weakening disturbance will move out of TX and toward the lower MS
Valley.

At the surface, high pressure will remain over much of the eastern
states and across the Gulf Coast. Southerly winds across the Plains
and around this high may support mid to upper 50s F dewpoints as far
north as IA and IL by 00Z, while higher dewpoints remain relegated
to southern TX. Here, scattered showers and thunderstorms will
likely be ongoing early on Tuesday where weak elevated instability
will remain.

...IL/IN/OH...
A surface trough is forecast to develop from Lower MI into southern
WI and northern IL by late afternoon, beneath the northwest flow
regime and with cool midlevel temperatures. Southwest surface winds
and daytime heating should lead to 40s and 50s F dewpoints, with a
relatively dry boundary layer overall. Models suggest at least
isolated late day and evening thunderstorms will develop ahead of
this trough, though instability levels are uncertain. Despite
marginal dewpoints/moisture, the cool temperatures aloft may support
a few cells capable of small hail from IL into IN by late afternoon.
Wind gust potential is more uncertain and dependent on storm
coverage/outflow production, with the dry boundary layer
conditionally helping strong gust potential into the evening and
perhaps overnight.

...Central CA...
Cold temperatures aloft north of the midlevel jet will support weak
instability over parts of the central Valleys. Given early
precipitation and clouds, as well as marginal low-level shear,
severe storms appear unlikely. However, a few strong storms may
occur late in the afternoon if sufficient heating occurs behind the
early day rain. Small hail appears most probable with the strongest
cells.

..Jewell.. 04/21/2026

$$

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ACUS01 KWNS 211240
SWODY1
SPC AC 211239

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0739 AM CDT Tue Apr 21 2026

Valid 211300Z - 221200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Organized severe thunderstorms are not currently forecast across the
contiguous United States through tonight.

...IL/IN...
Morning water-vapor imagery shows a subtle disturbance over the mid
MO Valley, which is forecast to quickly move southeast into the
southern Great Lakes by early evening. An associated surface trough
is forecast to develop from Lower MI into southern WI and northern
IL by late afternoon. Despite modest moisture (upper 40s to mid 50s
deg F surface dewpoints) returning northward into the Cornbelt, cold
mid-level temperatures (around -16 to -18 deg C at 500 mb) per
forecast soundings and heating will yield weak instability by
mid-late afternoon. Models continue to show isolated to scattered
storms late today into the evening. It remains uncertain whether a
couple of stronger cells will yield a threat of hail beyond a risk
for small hail. This activity will likely diminish by mid-late
evening as it moves southeast into central portions of IL/IN.

...Central CA...
Strong cyclonic flow associated with a mid-level low and associated
trough will move across central CA into the Great Basin during the
period. Cold temperatures aloft north of the midlevel jet will
support weak instability over parts of the central valleys. Given
early precipitation and clouds, as well as marginal low-level shear,
severe storms appear unlikely. However, a few strong storms may
occur late in the afternoon if sufficient heating occurs behind the
early day rain. Small hail appears most probable with the strongest
cells.

..Smith/Thompson.. 04/21/2026

$$

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ACUS01 KWNS 211553
SWODY1
SPC AC 211551

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1051 AM CDT Tue Apr 21 2026

Valid 211630Z - 221200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
OVER THE CA CENTRAL VALLEY...AND OVER PORTIONS OF NORTHERN IL/IN...

...SUMMARY...
Isolated strong thunderstorms are possible in the California Central
Valley, capable of gusty winds and perhaps a tornado or two. Other
strong storms are possible in parts of northern IN/IL where gusty
winds may occur.

...Central CA...
Morning water vapor loop shows a well-defined shortwave trough
approaching the coast of central CA. An associated mid/upper level
jet will nose into CA, with forcing for ascent in the left-front
quadrant of the jet aiding in the development of afternoon/evening thunderstorms over parts of the Central Valley. Forecast soundings
show steep low and mid level lapse rates and sufficient CAPE for a
few robust updrafts. Vertical shear will be strong enough for
supercell structures, including a risk of a tornado or two, small
hail, and gusty winds.

...Northern IN/IL...
A fast-moving shortwave trough currently over IA/MN will track
quickly southeastward into WI/IL/IN this afternoon. Visible
satellite and radar imagery show a line of high-based thunderstorms
developing ahead of the trough over southern WI. As these storms
track into northern IL/IN, continued heating/weak destabilization
will increase the risk of gusty/locally damaging wind gusts and
small hail in the strongest cores this afternoon.

..Hart/Flournoy.. 04/21/2026

$$

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ACUS01 KWNS 211949
SWODY1
SPC AC 211947

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0247 PM CDT Tue Apr 21 2026

Valid 212000Z - 221200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
THE OHIO VALLEY AND THE CALIFORNIA CENTRAL VALLEY...

...SUMMARY...
Isolated strong thunderstorms are possible in the California Central
Valley, capable of gusty winds and perhaps a tornado or two. Other
strong storms are possible over parts of the Great Lakes region.

...20Z Update...
The primary changes to the outlook were to extend Category
1/Marginal Risk probabilities in CA farther north into the
Sacramento Valley, and expand severe probabilities in the Great
Lakes area to include far southwestern Lower MI. In CA, MRMS mosaic
radar imagery shows convection deepening farther north into the
Sacramento Valley, and where 19Z mesoanalysis shows well over 100
J/kg 0-3 km CAPE in place with a focused corridor of low-level
vertically oriented vorticity. As such, a low-topped supercell could
develop this afternoon or evening, which may be capable of producing
hail/wind and perhaps a brief tornado. Thunderstorms, with a history
of producing marginally severe hail over extreme southeastern WI,
are currently traversing far southern Lake MI, and have been slow to
diminish. A corridor of MUCAPE is developing over far southwestern
Lower MI as 8+ C/km mid-level lapse rates, coinciding with a
southwesterly WAA regime, overspreads the Great Lakes. Therefore,
Category 1/Marginal risk wind/hail probabilities were extended
northeastward into far southwestern Lower MI to account for
potential strong thunderstorms in this region.

..Squitieri.. 04/21/2026

.PREV DISCUSSION... /ISSUED 1051 AM CDT Tue Apr 21 2026/

...Central CA...
Morning water vapor loop shows a well-defined shortwave trough
approaching the coast of central CA. An associated mid/upper level
jet will nose into CA, with forcing for ascent in the left-front
quadrant of the jet aiding in the development of afternoon/evening thunderstorms over parts of the Central Valley. Forecast soundings
show steep low and mid level lapse rates and sufficient CAPE for a
few robust updrafts. Vertical shear will be strong enough for
supercell structures, including a risk of a tornado or two, small
hail, and gusty winds.

...Northern IN/IL...
A fast-moving shortwave trough currently over IA/MN will track
quickly southeastward into WI/IL/IN this afternoon. Visible
satellite and radar imagery show a line of high-based thunderstorms
developing ahead of the trough over southern WI. As these storms
track into northern IL/IN, continued heating/weak destabilization
will increase the risk of gusty/locally damaging wind gusts and
small hail in the strongest cores this afternoon.

$$

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ACUS01 KWNS 220047
SWODY1
SPC AC 220045

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0745 PM CDT Tue Apr 21 2026

Valid 220100Z - 221200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SAN JOAQUIN VALLEY OF CENTRAL CALIFORNIA...

...SUMMARY...
Isolated strong thunderstorms are possible in the San Joaquin Valley
of central California early this evening, capable of isolated severe
gusts and perhaps a tornado.

...San Joaquin Valley...
Latest water vapor imagery shows an upper-level low just off the
coast of far northern California. A mid-level jet is wrapped around
the southern edge of the system. Within the left exit region of the
mid-level jet, a couple of strong to severe thunderstorms are
ongoing in the San Joaquin Valley. Strong lift is present along the
northern gradient of the mid-level jet, which is coincident with a
pocket of instability, with the RAP showing MLCAPE in the 250 to 500
J/kg range. Over this area, the mid-level jet is creating deep-layer
shear exceeding 85 knots. This environment will continue support a
marginal severe threat. Isolated severe wind gusts and perhaps a
tornado will be possible for another hour this evening.

..Broyles.. 04/22/2026

$$

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ACUS01 KWNS 220555
SWODY1
SPC AC 220554

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1254 AM CDT Wed Apr 22 2026

Valid 221200Z - 231200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE HIGH PLAINS AND FROM NORTHEAST INDIANA INTO CENTRAL AND NORTHERN
OHIO...

...SUMMARY...
Severe thunderstorms with hail and isolated severe gusts will be
possible across parts of the High Plains this afternoon and evening.
Isolated severe gusts and hail will also be possible in parts of
northeast Indiana and Ohio.

...High Plains...
At mid-levels today, heights will fall across much of the High
Plains, as a ridge moves toward the Mississippi Valley and a trough
moves through the Intermountain West. In response, a lee trough will
sharpen across the High Plains. To the east of the surface trough,
moisture advection will take place. Surface dewpoints will increase
into the 55 to 60 F range to the east of a well-developed dryline
extending from west Texas northward into southwest Nebraska.
Although large-scale ascent will be weak along the dryline,
low-level convergence will aid isolated convective initiation during
the mid to late afternoon. The most favorable location for storm
development will be from northwest Kansas into west-central Nebraska
and southern South Dakota, as the low-level jet strengthens in the
late afternoon and early evening. In addition to moderate
instability, 0-6 km shear is forecast to increase into the 35 to 40
knot range by early evening. This, combined with 700-500 mb lapse
rates in the 8.5 to 9 C/km range should be favorable for supercells
with isolated large hail, with the greatest potential from northwest
Kansas into west-central Nebraska. A few severe wind gusts may also
occur from western Kansas into South Dakota.

Further south into west Texas and the Oklahoma Panhandle, the lift
supportive of convective development will be confined to weak
low-level convergence along the dryline. If a storm can initiate,
then a supercell could develop with potential for large hail.

...Northeast Indiana/Central and Northern Ohio...
A mid-level ridge will move into the upper Mississippi Valley today,
as northwesterly mid-level flow persists over the Great Lakes
region. At the surface, a slow-moving front will remain in place
from southern Wisconsin eastward into southern Michigan. Scattered thunderstorms will develop this afternoon along and to the south of
the front as surface temperatures warm and low-level convergence
increases. Model forecasts in the mid to late afternoon from
northeast Indiana into central and northern Ohio have MLCAPE in the
2000 to 2500 J/kg range, with 0-3 km lapse rates near 8.5 C/km. In
addition, 0-6 km shear is forecast to approach 30 knots, which could
be enough for a marginal severe threat. Isolated severe gusts and
hail will be possible with the stronger multicells in areas that
destabilize the most.

..Broyles/Chalmers.. 04/22/2026

$$

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ACUS01 KWNS 221239
SWODY1
SPC AC 221237

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0737 AM CDT Wed Apr 22 2026

Valid 221300Z - 231200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS
AFTERNOON/EVENING FOR PARTS OF THE HIGH PLAINS/NORTHERN PLAINS...AND
FROM NORTHEAST INDIANA INTO NORTHERN OHIO...

...SUMMARY...
Isolated strong-severe thunderstorms with strong gusts and hail will
be possible across parts of the High Plains this afternoon and
evening, as well as from northeast Indiana into northern Ohio.

...High Plains this afternoon/evening...
In response to a shortwave trough digging south-southeastward over
BC/AB, a closed low over the Great Basin will evolve into a more
open wave and eject northeastward to the northern High Plains by
early Thursday. An associated, deep lee cyclone will develop
eastward from MT to near the ND/SK border, with a lee trough
extending southward into the central/southern High Plains. East of
the lee trough, low-level moisture (boundary-layer dewpoints in the
55-60 F range) will spread northward today from TX/OK to KS/NE.
Diurnal mixing will likely limit the quality of the moisture farther
north into the Dakotas. Thus, a few high-based thunderstorms will
be possible this afternoon/evening from NE into SD along the lee
trough with deep mixing, where inverted-v profiles will favor strong
outflow gusts.

A narrow zone of moderate buoyancy is expected along the dryline
from southwest NE and western KS into west TX, where deep-layer
vertical shear will be sufficient for supercells. Only limited
height falls and a warm elevated mixed layer, in combination with
somewhat limited parcel residence times in the dryline circulation,
suggest that storm coverage will be isolated at best. There will be
a conditional threat for isolated large hail with any sustained
storms.

...Dakotas tonight...
The threat for thunderstorms may increase tonight as a result of
ascent preceding the midlevel trough, and a modest increase in
low-level moisture with a strengthening low-level jet. Much of the
convection will likely be rooted above the surface, but could still
produce strong outflow gusts and marginally severe hail.

...IN/OH this afternoon/evening...
Residual low-level moisture and surface heating along a diffuse
baroclinic zone will support thunderstorm development this afternoon
from northeast IN into northern OH. Though deep-layer wind profiles
will not be particularly strong, relatively cool midlevel
temperatures and weak-moderate buoyancy could support marginally
severe hail and gusty outflow winds with the strongest storms.

..Thompson/Bentley.. 04/22/2026

$$

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ACUS01 KWNS 221630
SWODY1
SPC AC 221628

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1128 AM CDT Wed Apr 22 2026

Valid 221630Z - 231200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS
AFTERNOON/EVENING FOR PARTS OF THE HIGH PLAINS/NORTHERN PLAINS...AND
ACROSS FAR SOUTHERN LOWER MICHIGAN...NORTHEAST INDIANA INTO NORTHERN
OHIO...

...SUMMARY...
Isolated strong-severe thunderstorms with strong gusts and hail will
be possible across parts of the High Plains this afternoon and
evening, as well as from northeast Indiana into northern Ohio.

...Synopsis...
Recent surface analysis shows an airmass modifying under low-level
moisture advection across the southern and central Plains, with mid
50s dewpoints reaching through central KS and into eastern
NE/western IA. This moderate low-level moisture also extends
eastward from IA into northern IL and IN, just south of a stationary
boundary that demarcates a drier, more stable airmass across much of
the Great Lakes from the modifying airmass farther south/southwest.

This analysis also reveals a pair of surface lows, one over
north-central MT and the other over far northeast WY/far southeast
MT, linked by modest surface troughing. A wavy surface trough also
extends southward to another low over southeast CO. Thunderstorm
development is anticipated today/tonight near these lows and their
related surface boundaries. In particular, strong to isolated severe thunderstorms appear possible near the northeast WY/far southeast MT
low as it moves eastward across SD, as well as in the vicinity of
the stationary boundary across northern IN and OH.

...IN/OH...
Weak surface low over southern Lower MI has already contributed to
thunderstorm development. The airmass downstream of this low, and
south of the stationary boundary that extends east-to-west near the
MI and IN/OH border vicinity, will likely destabilize throughout the
day amid continued low-level moisture advection and strong diurnal
heating. This destabilization coupled with low-level convergence
near the low and boundary will support increasing thunderstorm
coverage. Deep-layer wind profiles will be modest, but cool
mid-level temperatures and weak-moderate buoyancy could support
isolated severe hail and gusty outflow winds with the strongest
storms.

...High Plains...
Primary surface low over central MT is forecast to deepen today as a
closed upper low currently over the Great Basin ejects northeastward
while evolving towards a more open wave. At the same time, a
secondary surface low (currently over far northeast WY/far southeast
MT) is forecast to move eastward across SD, interacting with the
modifying airmass across the northern/central Plains. Expectation is
for this airmass to be deeply mixed, with perhaps some minimal
buoyancy atop the well-mixed boundary layer. Development of a few
high-based thunderstorms is possible this afternoon/evening from NE
into SD, as well as northeast MT, along the trough where deep mixing
and inverted-v profiles will favor strong outflow gusts.

Farther south, an even more conditional risk is anticipated along a
sharpening dryline from southwest NE and western KS into west TX.
Given the limited large-scale forcing and only weak low-level
convergence, warm mid-level temperatures and related capping
associated with a notable elevated mixed layer will likely suppress thunderstorm development. Here, deep-layer vertical shear will be
sufficient for supercells, and a conditional risk for large hail and
strong gusts exists with any updrafts that are able to persist and
mature.

...Western/Central NE into the Dakotas...
Additional thunderstorms are possible tonight from western/central
NE into the Dakotas as an eastward-progressing cold front interacts
with low-level moisture continuing to advect northward across the
Plains and a strengthening low-level jet. These storms will likely
be elevated behind the front, with some isolated hail possible early
in the convective cycle. Additionally, mid-level dry air will likely
remain across the region, supporting the potential for strong
outflow gusts despite the storms elevated character.

..Mosier/Lyons.. 04/22/2026

$$

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ACUS01 KWNS 221953
SWODY1
SPC AC 221951

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0251 PM CDT Wed Apr 22 2026

Valid 222000Z - 231200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
THE HIGH PLAINS INTO THE NORTHERN PLAINS AND EASTERN PARTS OF THE
OHIO VALLEY...

...SUMMARY...
Isolated strong-severe thunderstorms with strong gusts and hail will
be possible across parts of the High Plains this afternoon and
evening, as well as from northeast Indiana into northern Ohio.

...20Z Update...
The previous forecast (see below) remains on track, with mainly
minor adjustments made to the general thunder and severe
probabilities to reflect the latest observations and guidance
consensus.

..Squitieri/Mosier.. 04/22/2026

.PREV DISCUSSION... /ISSUED 1128 AM CDT Wed Apr 22 2026/

...Synopsis...
Recent surface analysis shows an airmass modifying under low-level
moisture advection across the southern and central Plains, with mid
50s dewpoints reaching through central KS and into eastern
NE/western IA. This moderate low-level moisture also extends
eastward from IA into northern IL and IN, just south of a stationary
boundary that demarcates a drier, more stable airmass across much of
the Great Lakes from the modifying airmass farther south/southwest.

This analysis also reveals a pair of surface lows, one over
north-central MT and the other over far northeast WY/far southeast
MT, linked by modest surface troughing. A wavy surface trough also
extends southward to another low over southeast CO. Thunderstorm
development is anticipated today/tonight near these lows and their
related surface boundaries. In particular, strong to isolated severe thunderstorms appear possible near the northeast WY/far southeast MT
low as it moves eastward across SD, as well as in the vicinity of
the stationary boundary across northern IN and OH.

...IN/OH...
Weak surface low over southern Lower MI has already contributed to
thunderstorm development. The airmass downstream of this low, and
south of the stationary boundary that extends east-to-west near the
MI and IN/OH border vicinity, will likely destabilize throughout the
day amid continued low-level moisture advection and strong diurnal
heating. This destabilization coupled with low-level convergence
near the low and boundary will support increasing thunderstorm
coverage. Deep-layer wind profiles will be modest, but cool
mid-level temperatures and weak-moderate buoyancy could support
isolated severe hail and gusty outflow winds with the strongest
storms.

...High Plains...
Primary surface low over central MT is forecast to deepen today as a
closed upper low currently over the Great Basin ejects northeastward
while evolving towards a more open wave. At the same time, a
secondary surface low (currently over far northeast WY/far southeast
MT) is forecast to move eastward across SD, interacting with the
modifying airmass across the northern/central Plains. Expectation is
for this airmass to be deeply mixed, with perhaps some minimal
buoyancy atop the well-mixed boundary layer. Development of a few
high-based thunderstorms is possible this afternoon/evening from NE
into SD, as well as northeast MT, along the trough where deep mixing
and inverted-v profiles will favor strong outflow gusts.

Farther south, an even more conditional risk is anticipated along a
sharpening dryline from southwest NE and western KS into west TX.
Given the limited large-scale forcing and only weak low-level
convergence, warm mid-level temperatures and related capping
associated with a notable elevated mixed layer will likely suppress thunderstorm development. Here, deep-layer vertical shear will be
sufficient for supercells, and a conditional risk for large hail and
strong gusts exists with any updrafts that are able to persist and
mature.

...Western/Central NE into the Dakotas...
Additional thunderstorms are possible tonight from western/central
NE into the Dakotas as an eastward-progressing cold front interacts
with low-level moisture continuing to advect northward across the
Plains and a strengthening low-level jet. These storms will likely
be elevated behind the front, with some isolated hail possible early
in the convective cycle. Additionally, mid-level dry air will likely
remain across the region, supporting the potential for strong
outflow gusts despite the storms elevated character.

$$

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ACUS01 KWNS 230029
SWODY1
SPC AC 230028

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0728 PM CDT Wed Apr 22 2026

Valid 230100Z - 231200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE CENTRAL AND NORTHERN PLAINS...

...SUMMARY...
Thunderstorms with isolated severe gusts and hail will be possible
across parts of the central and northern Plains this evening into
tonight.

...Central and Northern Plains...
Water vapor imagery shows a mid-level low over the northern Rockies,
with cyclonic southwesterly flow located from the Desert Southwest
into the northern Plains. At the surface, a north-to-south oriented
trough is present across the High Plains. Isolated to scattered
thunderstorms are ongoing to the east of the trough from northwest
Nebraska into west-central South Dakota. Additional storms are
ongoing in northeastern Montana to the west of a surface low. As the
low-level jet strengthens across the region tonight, continued
thunderstorm development is expected. A hail and wind-damage threat
will be possible along and near an axis of weak instability from
west-central Nebraska into far southern North Dakota. A wind-damage
threat will also be possible with storms currently ongoing in
northeast Montana.

..Broyles.. 04/23/2026

$$

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ACUS01 KWNS 230503
SWODY1
SPC AC 230502

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1202 AM CDT Thu Apr 23 2026

Valid 231200Z - 241200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
EASTERN KANSAS...

...SUMMARY...
Severe thunderstorms are expected to develop this afternoon and
evening from the southern and central Plains into the lower to mid
Missouri Valley, and upper Mississippi Valley. Tornadoes, large hail
and severe wind gusts will be possible.

...Southern and Central Plains/Lower to Mid Missouri Valley/Upper
Mississippi Valley...
An upper-level trough will move through the central Rockies this
morning, and into the High Plains this afternoon as a 50 to 60 knot
mid-level jet moves into the Great Plains. At the surface, a cold
front will advance southeastward into the mid Missouri Valley and
central Plains. Moisture advection ahead of the front will increase
surface dewpoints into the mid 60s F by afternoon. This will
contribute to moderate destabilization as surface temperatures warm
along the moist axis. Thunderstorms are first expected to develop
ahead of the front over the mid Missouri and upper Mississippi
Valleys in the early to mid afternoon. Convective coverage will
rapidly expand southward into eastern Kansas by late afternoon, and
into far northern Oklahoma during the early to mid evening. MCS
development appears likely to take place along and ahead of the
front.

The best environment for severe storms will be in eastern Kansas. In
this area, RAP forecast soundings late this afternoon ahead of the
front have MLCAPE peaking just above 3000 J/kg, with 700-500 mb
lapse rates in the 7.5 to 8 C/km range. 0-6 km shear is forecast to
be in the 35 to 40 knot range. This environment will support
supercells with large hail. Hailstones greater than 2 inches in
diameter will be possible with the more intense supercells. In
addition, 0-3 km storm-relative helicity is forecast to increase
into the 300 to 400 m2/s2 range by 00Z, as at 40 to 50 knot
low-level jet strengthens. This will support tornadoes with
supercells. Supercells will initially be discrete but a line is
expected to form by early evening. As the line forms, rotating cells
within the line should also be capable of producing tornadoes. A
strong tornado or two will be possible late this afternoon and early
this evening. A wind-damage threat is also expected to develop. The
southern edge of the line will impact far northern Oklahoma in the
early to mid evening. Convective coverage should be isolated further
south across the rest of Oklahoma.

Further north-northeast into Iowa and southern Minnesota,
instability will not be as strong. RAP forecast soundings by late
afternoon have MLCAPE peaking in the 1500 to 2000 J/kg range. This,
combined with 30 to 35 knots of deep-layer shear and 700-500 mb
lapse rates of 7 to 7.5 C/km should support large hail with
supercells. Supercells and developing line segments should also be
capable of producing wind damage, hail and a tornado or two.

..Broyles/Chalmers.. 04/23/2026

$$

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ACUS01 KWNS 231251
SWODY1
SPC AC 231250

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0750 AM CDT Thu Apr 23 2026

Valid 231300Z - 241200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS LATER THIS AFTERNOON/EVENING FOR EASTERN KANSAS INTO EXTREME NORTHERN
OKLAHOMA...

...SUMMARY...
Severe thunderstorms are expected to develop this afternoon and
evening from the southern and central Plains into the lower to mid
Missouri Valley, and upper Mississippi Valley. Tornadoes, large hail
and severe wind gusts will be possible.

...MN/IA to KS/northern OK this afternoon into tonight...
The interaction of a southeastward moving midlevel trough over
southern BC/AB and a northeastward moving trough over the western
Dakotas will lead to the formation of a deep closed low over
southern SK. An associated, occluding surface cyclone will weaken
across southern MB by this evening, as a trailing cold front moves
across MN/IA/KS/MO and northern OK. Low-level moisture will spread
northward across IA/MN in advance of the cold front, beneath the
northeast edge of an elevated mixed layer. Surface heating and the
degree of buoyancy may be limited by extensive clouds from IA into
MN, and forecast wind profiles show complex/messy hodographs
structures (stronger low-level shear lingering across IA). Mixed
convective modes are expected along and ahead of the front this
afternoon, which could produce occasional wind damage, large hail
and perhaps a couple of tornadoes.

The more substantial severe threat is expected late this afternoon
through late evening from eastern KS into far northern OK, near and
just northeast of a cold front/dryline triple point and weak
secondary cyclone. A midlevel speed max near the Four Corners will
progress eastward to the TX Panhandle by this evening, with ascent
in the left exit region of the jet coincident with the triple point
near or just north of the KS/OK border. An influx of mid 60s
boundary-layer dewpoints beneath steep midlevel lapse rates will
contribute to MLCAPE of 2000-3000 J/kg, with weakening convective
inhibition across KS by mid afternoon.

Storm development is expected along the cold front in KS by mid
afternoon, with storms expected to develop southward to near the
triple point. The large buoyancy, steep midlevel lapse rates and
deep-layer shear sufficient for supercells will favor very large
hail (2-3 inches in diameter) with the initial/more discrete storms.
The tornado threat will peak this evening as low-level
shear/hodograph curvature increase near the KS/OK border - there
will be strong tornado potential with the anchor/southern supercells
near the triple point. Upscale storm growth and cold pool
development will favor a more linear convective mode with occasional
wind damage as the outflow/effective cold front spreads
southeastward into northeast OK and southwest MO overnight.

...OK dryline this evening...
Storm development along the dryline in OK is uncertain late this afternoon/evening. Forecast soundings suggest that the degree of
surface heating/mixing along the dryline and residence time in the
dryline circulation will be close to supporting deep convection. If
storms do form, the environment will conditionally favor very large
hail initially, and the possibility of an evening tornado threat
with any sustained storm.

..Thompson/Bentley.. 04/23/2026

$$

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ACUS01 KWNS 231615
SWODY1
SPC AC 231615

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
Issued by 15th OWS Scott Air Force Base IL
1115 AM CDT Thu Apr 23 2026

Valid 231630Z - 241200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS EASTERN
KANSAS...NORTHERN OKLAHOMA...

...SUMMARY...
Severe thunderstorms are expected to develop this afternoon and
evening from the southern and central Plains into the lower to mid
Missouri Valley, and upper Mississippi Valley. Tornadoes, large hail
and severe wind gusts will be possible.

...MN/IA to KS/northern OK this afternoon into tonight...
The interaction of a southeastward moving midlevel trough over
southern BC/AB and a northeastward moving trough over the western
Dakotas will lead to the formation of a deep closed low over
southern SK. An associated, occluding surface cyclone will weaken
across southern MB by this evening, as a trailing cold front moves
across MN/IA/KS/MO and northern OK. Low-level moisture will spread
northward across IA/MN in advance of the cold front, beneath the
northeast edge of an elevated mixed layer. Surface heating and the
degree of buoyancy may be limited by extensive clouds from IA into
MN, and forecast wind profiles show complex/messy hodographs
structures (stronger low-level shear lingering across IA). Mixed
convective modes are expected along and ahead of the front this
afternoon, which could produce occasional wind damage, large hail
and perhaps a couple of tornadoes.

The more substantial severe threat is expected late this afternoon
through late evening from eastern KS into northern OK, near and just
northeast of a cold front/dryline triple point and weak secondary
cyclone. A midlevel speed max near the Four Corners will progress
eastward to the TX Panhandle by this evening, with ascent in the
left exit region of the jet coincident with the triple point near or
just north of the KS/OK border. An influx of mid 60s boundary-layer
dewpoints beneath steep midlevel lapse rates will contribute to
MLCAPE of 2000-3000 J/kg, with weakening convective inhibition
across KS by mid afternoon.

Storm development is expected along the cold front in KS by mid
afternoon, with storms expected to develop southward to near the
triple point. The large buoyancy, steep midlevel lapse rates and
deep-layer shear sufficient for supercells will favor very large
hail (2-3 inches in diameter) with the initial/more discrete storms.
The tornado threat will peak this evening as low-level
shear/hodograph curvature increase near the KS/OK border - there
will be strong tornado potential with the anchor/southern supercells
near the triple point. Upscale storm growth and cold pool
development will favor a more linear convective mode with occasional
wind damage as the outflow/effective cold front spreads
southeastward into northeast OK and southwest MO overnight.

...OK dryline this evening...
Storm development along the dryline in OK is uncertain late this afternoon/evening. Forecast soundings suggest that the degree of
surface heating/mixing along the dryline and residence time in the
dryline circulation will be close to supporting deep convection. If
storms do form, the environment will conditionally favor very large
hail initially, and the possibility of an evening tornado threat
with any sustained storm.

..Afwa.. 04/23/2026

$$

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ACUS01 KWNS 231651
SWODY1
SPC AC 231615

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
Issued by 15th OWS Scott Air Force Base IL
1115 AM CDT Thu Apr 23 2026

Valid 231630Z - 241200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS EASTERN
KANSAS...NORTHERN OKLAHOMA...

...SUMMARY...
Severe thunderstorms are expected to develop this afternoon and
evening from the southern and central Plains into the lower to mid
Missouri Valley, and upper Mississippi Valley. Tornadoes, large hail
and severe wind gusts will be possible.

...MN/IA to KS/northern OK this afternoon into tonight...
The interaction of a southeastward moving midlevel trough over
southern BC/AB and a northeastward moving trough over the western
Dakotas will lead to the formation of a deep closed low over
southern SK. An associated, occluding surface cyclone will weaken
across southern MB by this evening, as a trailing cold front moves
across MN/IA/KS/MO and northern OK. Low-level moisture will spread
northward across IA/MN in advance of the cold front, beneath the
northeast edge of an elevated mixed layer. Surface heating and the
degree of buoyancy may be limited by extensive clouds from IA into
MN, and forecast wind profiles show complex/messy hodographs
structures (stronger low-level shear lingering across IA). Mixed
convective modes are expected along and ahead of the front this
afternoon, which could produce occasional wind damage, large hail
and perhaps a couple of tornadoes.

The more substantial severe threat is expected late this afternoon
through late evening from eastern KS into northern OK, near and just
northeast of a cold front/dryline triple point and weak secondary
cyclone. A midlevel speed max near the Four Corners will progress
eastward to the TX Panhandle by this evening, with ascent in the
left exit region of the jet coincident with the triple point near or
just north of the KS/OK border. An influx of mid 60s boundary-layer
dewpoints beneath steep midlevel lapse rates will contribute to
MLCAPE of 2000-3000 J/kg, with weakening convective inhibition
across KS by mid afternoon.

Storm development is expected along the cold front in KS by mid
afternoon, with storms expected to develop southward to near the
triple point. The large buoyancy, steep midlevel lapse rates and
deep-layer shear sufficient for supercells will favor very large
hail (2-3 inches in diameter) with the initial/more discrete storms.
The tornado threat will peak this evening as low-level
shear/hodograph curvature increase near the KS/OK border - there
will be strong tornado potential with the anchor/southern supercells
near the triple point. Upscale storm growth and cold pool
development will favor a more linear convective mode with occasional
wind damage as the outflow/effective cold front spreads
southeastward into northeast OK and southwest MO overnight.

...OK dryline this evening...
Storm development along the dryline in OK is uncertain late this afternoon/evening. Forecast soundings suggest that the degree of
surface heating/mixing along the dryline and residence time in the
dryline circulation will be close to supporting deep convection. If
storms do form, the environment will conditionally favor very large
hail initially, and the possibility of an evening tornado threat
with any sustained storm.

..Afwa.. 04/23/2026

$$

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ACUS01 KWNS 231945
SWODY1
SPC AC 231945

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
Issued by 15th OWS Scott Air Force Base IL
0245 PM CDT Thu Apr 23 2026

Valid 232000Z - 241200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS NORTH CENTRAL MINNESOTA...EASTERN KANSAS...NORTHERN OKLAHOMA...

...SUMMARY...
Severe thunderstorms are expected to develop this afternoon and
evening from the southern through central Plains and Minnesota into
the lower to mid Missouri Valley, and upper Mississippi Valley.
Tornadoes, large hail and severe wind gusts will be possible.

...MN/IA to KS/northern OK this afternoon into tonight...
The interaction of a southeastward moving midlevel trough over
southern BC/AB and a northeastward moving trough over the western
Dakotas will lead to the formation of a deep closed low over
southern SK. An associated, occluding surface cyclone will weaken
across southern MB by this evening, as a trailing cold front moves
across MN/IA/KS/MO and northern OK. Low-level moisture will spread
northward across IA/MN in advance of the cold front, beneath the
northeast edge of an elevated mixed layer. Surface heating and the
degree of buoyancy may be limited by extensive clouds from IA into
MN, and forecast wind profiles show complex/messy hodographs
structures (stronger low-level shear lingering across IA). Mixed
convective modes are expected along and ahead of the front this
afternoon, which could produce occasional wind damage, large hail
and perhaps a couple of tornadoes.

The more substantial severe threat is expected late this afternoon
through late evening from eastern KS into northern OK, near and just
northeast of a cold front/dryline triple point and weak secondary
cyclone. A midlevel speed max near the Four Corners will progress
eastward to the TX Panhandle by this evening, with ascent in the
left exit region of the jet coincident with the triple point near or
just north of the KS/OK border. An influx of mid 60s boundary-layer
dewpoints beneath steep midlevel lapse rates will contribute to
MLCAPE of 2000-3000 J/kg, with weakening convective inhibition
across KS by mid afternoon.

Storm development is expected along the cold front in KS by mid
afternoon, with storms expected to develop southward to near the
triple point. The large buoyancy, steep midlevel lapse rates and
deep-layer shear sufficient for supercells will favor very large
hail (2-3 inches in diameter) with the initial/more discrete storms.
The tornado threat will peak this evening as low-level
shear/hodograph curvature increase near the KS/OK border - there
will be strong tornado potential with the anchor/southern supercells
near the triple point. Upscale storm growth and cold pool
development will favor a more linear convective mode with occasional
wind damage as the outflow/effective cold front spreads
southeastward into northeast OK and southwest MO overnight.

...OK dryline this evening...
Storm development along the dryline in OK is uncertain late this afternoon/evening. Forecast soundings suggest that the degree of
surface heating/mixing along the dryline and residence time in the
dryline circulation will be close to supporting deep convection. If
storms do form, the environment will conditionally favor very large
hail initially, and the possibility of an evening tornado threat
with any sustained storm.

..Afwa.. 04/23/2026

$$

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ACUS01 KWNS 232024
SWODY1
SPC AC 231945

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
Issued by 15th OWS Scott Air Force Base IL
0245 PM CDT Thu Apr 23 2026

Valid 232000Z - 241200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS NORTH CENTRAL MINNESOTA...EASTERN KANSAS...NORTHERN OKLAHOMA...

...SUMMARY...
Severe thunderstorms are expected to develop this afternoon and
evening from the southern through central Plains and Minnesota into
the lower to mid Missouri Valley, and upper Mississippi Valley.
Tornadoes, large hail and severe wind gusts will be possible.

...MN/IA to KS/northern OK this afternoon into tonight...
The interaction of a southeastward moving midlevel trough over
southern BC/AB and a northeastward moving trough over the western
Dakotas will lead to the formation of a deep closed low over
southern SK. An associated, occluding surface cyclone will weaken
across southern MB by this evening, as a trailing cold front moves
across MN/IA/KS/MO and northern OK. Low-level moisture will spread
northward across IA/MN in advance of the cold front, beneath the
northeast edge of an elevated mixed layer. Surface heating and the
degree of buoyancy may be limited by extensive clouds from IA into
MN, and forecast wind profiles show complex/messy hodographs
structures (stronger low-level shear lingering across IA). Mixed
convective modes are expected along and ahead of the front this
afternoon, which could produce occasional wind damage, large hail
and perhaps a couple of tornadoes.

The more substantial severe threat is expected late this afternoon
through late evening from eastern KS into northern OK, near and just
northeast of a cold front/dryline triple point and weak secondary
cyclone. A midlevel speed max near the Four Corners will progress
eastward to the TX Panhandle by this evening, with ascent in the
left exit region of the jet coincident with the triple point near or
just north of the KS/OK border. An influx of mid 60s boundary-layer
dewpoints beneath steep midlevel lapse rates will contribute to
MLCAPE of 2000-3000 J/kg, with weakening convective inhibition
across KS by mid afternoon.

Storm development is expected along the cold front in KS by mid
afternoon, with storms expected to develop southward to near the
triple point. The large buoyancy, steep midlevel lapse rates and
deep-layer shear sufficient for supercells will favor very large
hail (2-3 inches in diameter) with the initial/more discrete storms.
The tornado threat will peak this evening as low-level
shear/hodograph curvature increase near the KS/OK border - there
will be strong tornado potential with the anchor/southern supercells
near the triple point. Upscale storm growth and cold pool
development will favor a more linear convective mode with occasional
wind damage as the outflow/effective cold front spreads
southeastward into northeast OK and southwest MO overnight.

...OK dryline this evening...
Storm development along the dryline in OK is uncertain late this afternoon/evening. Forecast soundings suggest that the degree of
surface heating/mixing along the dryline and residence time in the
dryline circulation will be close to supporting deep convection. If
storms do form, the environment will conditionally favor very large
hail initially, and the possibility of an evening tornado threat
with any sustained storm.

..Afwa.. 04/23/2026

$$

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ACUS01 KWNS 240101
SWODY1
SPC AC 240059

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0759 PM CDT Thu Apr 23 2026

Valid 240100Z - 241200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS ARTS OF
EASTERN KANSAS AND NORTHERN OKLAHOMA...

...SUMMARY...
Scattered severe thunderstorms will continue this evening from parts
of the southern and central Plains north-northeastward into the
lower Missouri and upper Mississippi Valleys. Tornadoes, large hail
and severe wind gusts are expected.

...Southern and Central Plains...
Latest water vapor imagery shows an upper-level trough over the
Great Plains, with an associated mid-level jet streak moving through
the base of the trough into the southern Plains. At the surface, a
cold front is advancing southeastward across far southeast Nebraska, east-central Kansas and far northern Oklahoma. Ahead of the front,
multiple line segments are ongoing. These broken lines are embedded
with discrete to semi-discrete supercells. The storms are located
along an axis of moderate to strong instability, with the RAP
showing MLCAPE in the 2500 to 3500 J/kg range. Over the top of this
moist and unstable airmass, flow is westerly around 50 knots. This
is creating moderate to strong deep-layer shear which will continue
to support supercells this evening. Steep mid-level lapse rates
approaching 8 C/km will be favorable for large hail. In addition,
the western edge of a 40 to 50 knot low-level jet will remain in
place over eastern Kansas. WSR-88D VWPs that are sampling the
low-level jet have 0-3 km storm-relative helicity in the 400 to 450
m2/s2 range, which will support a continued tornado threat. In
addition, a threat for wind damage will also continue through the
mid to late evening...see MCD 510.

...Lower Missouri Valley/Upper Mississippi Valley...
Southwesterly mid-level flow is in place over much of the
north-central U.S. At the surface, a cold front is located from
central Minnesota south-southwestward into the mid Missouri Valley.
A line of strong to severe thunderstorms is ongoing ahead of the
front from far southeastern Minnesota into central Iowa and far
northwestern Missouri. Moderate instability is analyzed ahead of the
line, with the RAP showing MLCAPE in the 1500 to 2000 J/kg range.
The thermodynamic environment will continue to be favorable for
isolated large hail. In addition, a 40 to 50 knot jet is analyzed
over east-central Iowa. As the low-level jet strengthens, tornadoes
will be possible with rotating cells embedded in the line. As the
line continues to move eastward through the mid to late evening,
wind damage will be possible with embedded supercells and bowing
line segments.

..Broyles.. 04/24/2026

$$

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ACUS01 KWNS 240554
SWODY1
SPC AC 240552

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1252 AM CDT Fri Apr 24 2026

Valid 241200Z - 251200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTHERN PLAINS...ARK-LA-TEX AND LOWER MISSISSIPPI VALLEY...

...SUMMARY...
Scattered severe thunderstorms are expected today from the Southern
Plains into the Ark-La-Tex and Lower Mississippi Valley. Large hail,
damaging winds and a few tornadoes will be possible. Isolated strong
wind gusts may also occur in parts of the lower Ohio Valley and
southern Great Lakes.

...Southern Plains/Ark-La-Tex/Lower Mississippi Valley...
A mid-level shortwave trough will move northeastward into the mid
Mississippi Valley today, as cyclonic west to southwesterly flow
remains over much of the south-central U.S. At the surface, an
outflow boundary will advance southward into the Ark-La-Tex and
lower Mississippi Valley this morning. Thunderstorms will be ongoing
along the boundary at the start of the period. These storms will
move southward across Arkansas, Louisiana and Mississippi. As
surface temperatures warm during the day, a wind-damage threat is
expected along the more organized parts of this line. A couple of
tornadoes will also be possible with rotating elements embedded in
the line.

Further west into the southern Plains, an axis of moderate
instability is forecast to develop by afternoon from east Texas into
far southern Oklahoma. Additional storms are expected to initiate
during the mid afternoon along an east-to-west axis of low-level
convergence in southeast Oklahoma. These storms are expected to move
southward into northeast Texas and northwestern Louisiana during the
late afternoon and early evening. Forecast soundings near the Red
River in far southeast Oklahoma late this afternoon have MLCAPE near
3500 J/kg, 0-6 km shear in the 30 to 35 knot range, and 700-500 mb
lapse rates near 8 C/km. This will support supercells with isolated
large hail. Hailstones of greater than 2 inches in diameter will be
possible. In addition, 0-3 km storm-relative helicity is forecast to
reach near 225 m2/s2, which will support a tornado threat with
supercells. If the storms can transition into a short intense line
segment, then a localized swath of wind damage may also occur.

...Southern Great Lakes/Ohio Valley...
A mid-level shortwave trough, and an associated cold front will move northeastward into the Great Lakes region today. Ahead of the front,
a moist airmass will be in place from the Lower Ohio Valley
northward into lower Michigan. As surface temperatures warm during
the day, surface dewpoints in the lower 60s F will contribute to
weak destabilization. This, combined with increasing low-level
convergence will support thunderstorm development ahead of the
front. These storms will move eastward across the southern Great
Lakes and Ohio Valley during the afternoon. Forecast soundings ahead
of the storms have very steep low-level lapse rates approaching 8
C/km, which could support an isolated wind-damage threat.

..Broyles/Moore.. 04/24/2026

$$

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ACUS01 KWNS 241232
SWODY1
SPC AC 241230

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0730 AM CDT Fri Apr 24 2026

Valid 241300Z - 251200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
SOUTHEAST OKLAHOMA AND THE ARKLATEX...

...SUMMARY...
Scattered severe thunderstorms are expected today from parts of the
southern Plains into the ArkLaTex and lower Mississippi Valley.
Large hail, damaging winds, and a few tornadoes will be possible.
The greatest threat for supercells with very large hail (2+ inches)
should focus across parts of southeast Oklahoma into the ArkLaTex.

...Southern Plains into the ArkLaTex/Lower Mississippi Valley...
A band of mainly sub-severe thunderstorms ongoing this morning from
eastern OK into AR and southern MO is being aided by southwesterly
warm/moist advection at low levels. With time, this forcing should
weaken, and a decrease in convective intensity should continue
through late morning. Outflow from this convection is forecast to
extend from south-central/southeast OK into AR this afternoon, and
should serve as a focus for additional robust thunderstorms later
today. Daytime heating of a moist airmass already present across
much of the southern Plains into the ArkLaTex and lower MS Valley
will aid in the development of moderate to strong instability by mid
afternoon along/south of the residual outflow and east of a surface
dryline extending from northeast to south-central TX. The greatest
instability should exist across southeast OK/northeast TX, where
steep mid-level lapse rates will likely still exist. A weak surface
low should also be in place across northeast TX by mid to late
afternoon.

Large-scale forcing aloft will remain fairly nebulous/weak across
the southern Plains this afternoon, as a prominent/closed
upper-level low remains centered over south-central Canada. Still,
multiple robust thunderstorms should develop by 19-22Z across
southeast OK along/near the residual outflow boundary as MLCIN
becomes minimal with robust diurnal heating, and as westerly
mid/upper-level flow modestly strengthens across the ArkLaTex
through early evening. This convection will become organized and
likely supercellular given the presence of around 30-40 kt of
deep-layer shear. Large to very large hail (potentially up to
1.5-2.5 inches in diameter) should be the main threat with these
cells initially. Lower confidence in convective initiation exists
with southwestward extent along the dryline in TX, but at least a conditional/low threat for severe hail remains apparent.

With time, some clustering may occur with an increased damaging wind
threat as convection spreads east-southeastward across the ArkLaTex
through the evening. One or more clusters may also redevelop along
the outflow from ongoing convection across the lower MS Valley this
afternoon, with a threat for mainly scattered damaging winds.
Low-level flow is not forecast to be overly strong (15-25 kt at 850
mb), but ample instability and the presence of locally backed
near-surface winds near the outflow boundary may support enough 0-1
km SRH for a few tornadoes, especially across southeast OK into the
ArkLaTex with any persistent supercells. An Enhanced Risk has been
introduced across this region given increased confidence in multiple
supercells with significant severe hail potential developing through
the afternoon/evening.

...Great Lakes/Ohio Valley...
A weak mid-level shortwave trough will move northeastward across the
Midwest and Upper Great Lakes today. Convection ahead of a cold
front has generally weakened this morning across the mid MS Valley.
Modest low-level moisture is forecast to continue advancing
northward through the day ahead of the front, supporting weak
instability with filtered daytime heating. Loosely organized
clusters/cells that develop this afternoon may pose an isolated
threat for damaging winds as they move northeastward this
afternoon/evening.

..Gleason/Thompson.. 04/24/2026

$$

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ACUS01 KWNS 241632
SWODY1
SPC AC 241630

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1130 AM CDT Fri Apr 24 2026

Valid 241630Z - 251200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS
SOUTHEAST OKLAHOMA AND ARKLATEX...

...SUMMARY...
Scattered severe thunderstorms are expected today from parts of the
southern Plains into the ArkLaTex and lower Mississippi Valley.
Large hail, damaging winds, and a few tornadoes will be possible.
The greatest threat for supercells with very large hail (2+ inches)
should focus across parts of southeast Oklahoma to the ArkLaTex
region.

...Oklahoma/North Texas to ArkLaTex/Lower Mississippi Valley...
A persistent band of non-severe thunderstorms this morning, and its
related outflow, continue to settle southward across southeast
Oklahoma, south-central/southeast Arkansas into northwest
Mississippi. The southeastern-most portion of the convective line
may re-intensify across the ArkLaMiss today as the boundary layer
warms, with some potential for a secondary round of upscale-growing
storms into tonight across generally the same ArkLaMiss/Lower
Mississippi Valley region. This includes damaging winds and some
tornado potential, primarily QLCS-related, especially into this
evening/tonight via a somewhat stronger wind field.

The western periphery of the ongoing complex and its outflow should
continue to decelerate, stall, and modify through the afternoon,
setting the stage for a semi-corridor of heightened severe potential
via this modifying outflow in conjunction with the surface triple
point to this west, with intensifying storm development anticipated
toward the 4pm-6pm/21z-23z time frame across southeast Oklahoma and
nearby ArkLaTex. This will be in the presence of ample buoyancy and
steep mid-level lapse rates. Wind profiles will further support
intense supercells capable of large to very large hail, along with a
tornado risk, accentuated by backed low-level winds near the outflow
boundary and east of the triple point. With time, some clustering
may occur with an increased damaging wind threat as convection
spreads east-southeastward.

Additionally, locally intense storms may also focus farther west
across southern Oklahoma/Red River vicinity along/north of the southward-sagging front where relatively rich low-level moisture
will persist in the presence of strong deep-layer shear.

...Texas Dryline - North/Central TX to Hill Country/Rio Grande...
A highly conditional scenario exists in vicinity of the south/southwestward-extending dryline late this afternoon/early
evening, with a concerning (mostly hail) severe potential should
storms develop. Short-term guidance varies on the aggressiveness of eastward-mixing/dryline through peak heating, although the 12z Fort
Worth sounding sampled respectable warm-sector moisture content this
morning (upper quartile climo; 14.4 g/kg mean mixing ratio).
Regardless, a concerning high degree of instability (3000+ J/kg
MLCAPE) will exist near/east of the dryline late this afternoon.

Short-term models remain rather sparse on explicit indications of
near-dryline convective initiation. However, sufficient dry line
convergence and post-dryline heating/mixing could plausibly lead to
isolated but intense thunderstorm development in the presence of
negligible capping/boundary-layer inhibition. And while mid-level
capping will be more prevalent, especially with southward extent,
upstream 12z soundings from Midland/El Paso (both around -14C 500mb)
suggest that some additional mid-level cooling is probable. Notably
stronger mid/high-level winds were also observed in these RAOBs with
50+ kt winds and 100+ kt winds at 500mb/250mb, respectively.

Several sub-regional zones of potential isolated deep convective
development are at least plausible, including in closer proximity to
the surface triple point across North Texas/Metroplex general
vicinity, extending into parts of central Texas where low-level
mixing may be less impactful, and lastly in the immediate vicinity
of the Rio Grande, potentially influenced by possible storm
development across the border. If/where storms do develop late this afternoon/early evening, very large hail could occur along with
localized severe-caliber wind gusts.

...Great Lakes/Ohio Valley...
A weak/convectively influenced mid-level shortwave trough will move northeastward across the Midwest and Upper Great Lakes today.
Convection ahead of a cold front has generally weakened this morning
across the mid Mississippi Valley, but multi-layer cloud cover
remains prevalent. Modest-caliber low-level moisture will continue
to advect north-northeastward through the day ahead of the front,
supporting weak instability with filtered daytime heating. Loosely
organized clusters/cells that develop/intensify this afternoon may
pose an isolated threat for damaging winds as they move
northeastward this afternoon and evening. The residual clouds and a
weakening low-level wind field should curb the overall magnitude of
the severe risk, hence maintenance of MRGL/Category 1 risk.

...Western Nebraska...
A couple of stronger storms may develop late this afternoon/early
evening near a southeastward-moving front, further influenced by a
mid-level impulse embedded within the base of the large-scale trough
centered over the Canadian Prairies. In the presence of a strong
deep-layer wind field, modest-caliber CAPE atop a well-mixed
boundary layer could potentially yield an isolated severe gust/hail.

..Guyer/Weinman.. 04/24/2026

$$

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ACUS01 KWNS 241958
SWODY1
SPC AC 241956

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0256 PM CDT Fri Apr 24 2026

Valid 242000Z - 251200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR SOUTHEAST
OKLAHOMA INTO THE ARKLATEX...

...SUMMARY...
Scattered severe thunderstorms are expected today from parts of the
southern Plains into the ArkLaTex and lower Mississippi Valley.
Large hail, damaging winds, and a few tornadoes will be possible.
The greatest threat for supercells with very large hail (2+ inches)
should focus across parts of southeast Oklahoma to the ArkLaTex
region.

...20Z Update...
Much of the previous forecast (see below) remains on track. The
primary changes made to the current outlook were to trim severe
probabilities across portions of the OH Valley/Great Lakes, and the
Mid-MS Valley, where either the passage of a surface cold front, or
robust convection, has promoted boundary layer stabilization. More
minor changes involved small adjustments to current severe and
thunder probabilities ahead of storms to account for observations
and the latest guidance consensus.

..Squitieri.. 04/24/2026

.PREV DISCUSSION... /ISSUED 1130 AM CDT Fri Apr 24 2026/

...Oklahoma/North Texas to ArkLaTex/Lower Mississippi Valley...
A persistent band of non-severe thunderstorms this morning, and its
related outflow, continue to settle southward across southeast
Oklahoma, south-central/southeast Arkansas into northwest
Mississippi. The southeastern-most portion of the convective line
may re-intensify across the ArkLaMiss today as the boundary layer
warms, with some potential for a secondary round of upscale-growing
storms into tonight across generally the same ArkLaMiss/Lower
Mississippi Valley region. This includes damaging winds and some
tornado potential, primarily QLCS-related, especially into this
evening/tonight via a somewhat stronger wind field.

The western periphery of the ongoing complex and its outflow should
continue to decelerate, stall, and modify through the afternoon,
setting the stage for a semi-corridor of heightened severe potential
via this modifying outflow in conjunction with the surface triple
point to this west, with intensifying storm development anticipated
toward the 4pm-6pm/21z-23z time frame across southeast Oklahoma and
nearby ArkLaTex. This will be in the presence of ample buoyancy and
steep mid-level lapse rates. Wind profiles will further support
intense supercells capable of large to very large hail, along with a
tornado risk, accentuated by backed low-level winds near the outflow
boundary and east of the triple point. With time, some clustering
may occur with an increased damaging wind threat as convection
spreads east-southeastward.

Additionally, locally intense storms may also focus farther west
across southern Oklahoma/Red River vicinity along/north of the southward-sagging front where relatively rich low-level moisture
will persist in the presence of strong deep-layer shear.

...Texas Dryline - North/Central TX to Hill Country/Rio Grande...
A highly conditional scenario exists in vicinity of the south/southwestward-extending dryline late this afternoon/early
evening, with a concerning (mostly hail) severe potential should
storms develop. Short-term guidance varies on the aggressiveness of eastward-mixing/dryline through peak heating, although the 12z Fort
Worth sounding sampled respectable warm-sector moisture content this
morning (upper quartile climo; 14.4 g/kg mean mixing ratio).
Regardless, a concerning high degree of instability (3000+ J/kg
MLCAPE) will exist near/east of the dryline late this afternoon.

Short-term models remain rather sparse on explicit indications of
near-dryline convective initiation. However, sufficient dry line
convergence and post-dryline heating/mixing could plausibly lead to
isolated but intense thunderstorm development in the presence of
negligible capping/boundary-layer inhibition. And while mid-level
capping will be more prevalent, especially with southward extent,
upstream 12z soundings from Midland/El Paso (both around -14C 500mb)
suggest that some additional mid-level cooling is probable. Notably
stronger mid/high-level winds were also observed in these RAOBs with
50+ kt winds and 100+ kt winds at 500mb/250mb, respectively.

Several sub-regional zones of potential isolated deep convective
development are at least plausible, including in closer proximity to
the surface triple point across North Texas/Metroplex general
vicinity, extending into parts of central Texas where low-level
mixing may be less impactful, and lastly in the immediate vicinity
of the Rio Grande, potentially influenced by possible storm
development across the border. If/where storms do develop late this afternoon/early evening, very large hail could occur along with
localized severe-caliber wind gusts.

...Great Lakes/Ohio Valley...
A weak/convectively influenced mid-level shortwave trough will move northeastward across the Midwest and Upper Great Lakes today.
Convection ahead of a cold front has generally weakened this morning
across the mid Mississippi Valley, but multi-layer cloud cover
remains prevalent. Modest-caliber low-level moisture will continue
to advect north-northeastward through the day ahead of the front,
supporting weak instability with filtered daytime heating. Loosely
organized clusters/cells that develop/intensify this afternoon may
pose an isolated threat for damaging winds as they move
northeastward this afternoon and evening. The residual clouds and a
weakening low-level wind field should curb the overall magnitude of
the severe risk, hence maintenance of MRGL/Category 1 risk.

...Western Nebraska...
A couple of stronger storms may develop late this afternoon/early
evening near a southeastward-moving front, further influenced by a
mid-level impulse embedded within the base of the large-scale trough
centered over the Canadian Prairies. In the presence of a strong
deep-layer wind field, modest-caliber CAPE atop a well-mixed
boundary layer could potentially yield an isolated severe gust/hail.

$$

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ACUS01 KWNS 250102
SWODY1
SPC AC 250100

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0800 PM CDT Fri Apr 24 2026

Valid 250100Z - 251200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE ARK-LA-TEX...

...SUMMARY...
A severe threat will continue this evening from the southern Plains,
into the Ark-La-Tex and Lower Mississippi Valley. Large hail, wind
damage and a couple tornadoes will be possible. The strongest of
storms could produce hailstones greater than 2 inches in diameter.

...Southern Plains/Ark-La-Tex/Lower Mississippi Valley...
A mid-level shortwave trough is evident on water vapor over the
Ark-La-Tex this evening. Ahead of the trough, a cluster of strong to
severe thunderstorms is ongoing from near the Red River
northeastward across far southeast Oklahoma into western Arkansas.
This cluster is located at the northern end of an axis of strong
instability, with the RAP showing MLCAPE near the instability axis
in the 2500 to 3500 J/kg range. In this area, RAP forecast soundings
also show steep mid-level lapse rates, exceeding 7.5 C/km. In
addition to this favorable thermodynamic environment, a low to
mid-level speed max is evident over the Ark-La-Tex, where flow is
westerly at 45 to 50 knots. This is creating moderate to strong
deep-layer shear, which will continue to be favorable for severe
storms this evening. Cells that can remain semi-descrete will could
be supercellar and have potential for large to very large hail.
Hailstones greater than 2 inches in diameter will be possible with
the more intense storms. The large hail threat should persist for a
few more hours as the cluster interacts with the strong instability
over the Ark-La-Tex. Supercells could also be associated with a
wind-damage and tornado threat.

The cluster of storms is expected to gradually organize into a
linear MCS, moving east-southeastward into the lower Mississippi
Valley during the mid to late evening. Severe wind gusts will become
the primary threat as the line segment develops. A couple of QLCS
tornadoes will be possible as well. The severe threat may persist
into the early overnight period...See MCD 521 and 523.

..Broyles.. 04/25/2026

$$

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ACUS01 KWNS 250602
SWODY1
SPC AC 250600

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0100 AM CDT Sat Apr 25 2026

Valid 251200Z - 261200Z

...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
CENTRAL AND SOUTHEAST OKLAHOMA...

...SUMMARY...
Severe thunderstorms with large to very large hail, tornadoes and
wind damage will be likely today across parts of the southern Plains
and Arklatex. Hailstones greater than 3 inches in diameter and
strong tornadoes will be possible.

...Southern Plains/Ark-La-Tex...
A mid-level shortwave trough will move eastward across the southern
Rockies this morning and into the southern Plains this afternoon. At
the surface, a low will deepen across northwest Texas. Ahead of the
approaching trough, moisture advection will take place in the
southern Plains, as surface dewpoints over Oklahoma increase into
the mid to upper 60s F. This will contribute to strong
destabilization by afternoon from parts of north Texas into
Oklahoma. An outflow boundary over north Texas will move northward
this afternoon into southern Oklahoma. Low-level convergence will
increase along this boundary in the afternoon. Low-level convergence
will also increase along a front moving into central Oklahoma. These
two zones will be the focus for convective initiation this
afternoon. Severe storms are expected to develop and move
southeastward across much of Oklahoma and north Texas this afternoon
and evening.

RAP forecast soundings late this afternoon in far southern Oklahoma
to the north of the Dallas/Fort Worth Metroplex increase MLCAPE into
the 3000 to 4000 J/kg range and have 700-500 mb lapse rates near 8
C/km range. This combined with long hodographs and a tendency for
the storms to remain discrete will be very favorable for supercells
with large hail. Hailstones greater than 3 inches in diameter will
be possible with the more intense cores. In addition, a 25 to 30
knot low-level jet will be in place late this afternoon from north
Texas into east-central Oklahoma. This feature will create strong
low-level shear profiles favorable for tornadoes. Low-level shear
will be amplified by the boundary in southern Oklahoma. By early
this evening, forecast sounding near the western edge of the
low-level jet have 0-3 km storm-relative helicity in the 300 to 400
m2/s2 range. This will support a potential for strong tornadoes with
the more robust supercells. Also, a wind-damage threat will develop
with supercells. The wind-damage threat will continue through much
of the evening as a cluster of severe storms moves southeastward
toward the Ark-La-Tex.

...Central Plains...
A mid-level shortwave trough will move into the southern and central
Plains today. At the surface, a cold front will advance southward
through western and central Kansas into western Oklahoma. To the
east of the front, a well-defined moist axis will be located from
central Oklahoma into east-central Kansas. Along the western edge of
the moist airmass, a north-to-south corridor of low-level
convergence is forecast which will focus convective initiation. As
instability maximizes this afternoon, thunderstorms are expected to
develop and move southeastward across much of central and southern
Kansas into northern Oklahoma. Forecast soundings across this area
by late afternoon show moderate instability and 0-6 km shear in the
30 to 40 knot range, which will support a large hail and wind-damage
threat.

...Central and Southwest Texas...
A moist airmass will remain over much of the southern Plains today.
Along the northwestern edge of the moist sector, low-level
convergence will increase along a well-developed dryline. Although
large-scale ascent will remain minimal, isolated storms could
develop late this afternoon to the east of the dryline. Moderate
deep-layer shear and steep mid-level lapse rates will support an
isolated threat for large hail and severe wind gusts.

..Broyles/Moore.. 04/25/2026

$$

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ACUS01 KWNS 251252
SWODY1
SPC AC 251250

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0750 AM CDT Sat Apr 25 2026

Valid 251300Z - 261200Z

...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF CENTRAL/EASTERN OKLAHOMA AND FAR NORTH TEXAS...

...SUMMARY...
Severe thunderstorms with very large to giant hail (2 to 4+ inches
in diameter), tornadoes, and scattered damaging winds are expected
late this afternoon through tonight across parts of the southern
Plains and ArkLaTex. A couple of strong tornadoes are possible.

...Synopsis...
A closed mid/upper-level low will remain centered over Manitoba and Saskatchewan today, while generally zonal/westerly mid-level winds
persist over the southern Plains. A weak shortwave trough over the Southwest/southern Rockies this morning is forecast to eject
eastward over the southern/central Plains by late this afternoon. At
the surface, a convectively reinforced outflow boundary draped
across north-central/northeast TX will shift northward into OK as a
warm front today, while a low gradually deepens over northwest TX by
late afternoon/early evening. Rich low-level moisture characterized
by upper 60s to low 70s surface dewpoints will likely advance as far
north as central into southeast OK through peak diurnal heating,
with lesser moisture return farther north into northwest OK, KS, and
southeast NE ahead of a cold front. A dryline will extend
south-southwestward from the surface low across central into
south-central TX.

...Southern/Central Plains into the ArkLaTex...
Strong to locally extreme instability (MLCAPE 2500-4000+ J/kg) is
expected to develop along/east of the dryline in TX and south of the
warm front in OK by peak afternoon heating. The presence of
seasonably cool temperatures aloft and 7.5-8.5 C/km mid-level lapse
rates will also support this very favorable thermodynamic
environment. While large-scale ascent associated with the ejecting
mid-level shortwave trough is not expected to be overly robust, it
should be sufficient for at least isolated thunderstorm initiation
by mid afternoon to early evening (around 20-23Z), especially near
the warm front/dryline intersection in south-central OK.

40-50 kt of generally westerly effective bulk shear will support
intense supercells, with multiple right/left splits likely. This
activity will quickly intensify shortly after convective initiation,
and very large to giant hail appears likely (2-4+ inches in
diameter). The Enhanced/Moderate Risk areas have been expanded
slightly in OK and north TX to account for deviant thunderstorm
motions and the potential for multiple intense supercells to track east-southeastward along/near the warm front. A conditional risk for
supercells remains apparent farther south along the length of the
dryline in TX, although confidence in convective initiation remains
low. Have maintained the Marginal Risk for this potential, with some
expansion eastward in case isolated thunderstorms do initiate.

Modest southerly low-level winds (around 20-30 kt at 850 mb) will be
present through this evening across the southern Plains. Locally
enhanced 0-1 km SRH will be present near the warm front with backed near-surface winds. This will support a threat for tornadoes with
any right-split supercells that can remain surface based. A slight
increase in the low-level jet this evening and presence of very
strong to locally extreme buoyancy also suggests some threat for a
couple of EF-2+ tornadoes. With time this evening, convection may
grow upscale and pose a threat for scattered severe/damaging winds
as it spreads southeastward into the ArkLaTex.

Farther north in KS/NE, instability and low-level moisture is
expected to remain weaker/more limited. But, some supercells/small
clusters may eventually develop this afternoon and move
east-northeastward given sufficient deep-layer shear for updraft
organization. Isolated to scattered severe hail and damaging winds
should be the main threat with this activity through mid evening
before it eventually weakens.

...Lower Mississippi Valley/Central Gulf Coast...
A long-lived convective cluster has nearly moved offshore from the
coast of AL/MS/LA. In its wake, a rain-cooled airmass exists across
much of the lower MS Valley. This should hinder the development of
much surface-based instability through early afternoon. Still,
eventual re-destabilization should occur along/near the remnant
outflow boundary. Isolated cells that may develop could pose some
risk for hail and damaging winds.

..Gleason/Thompson.. 04/25/2026

$$

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ACUS01 KWNS 251633
SWODY1
SPC AC 251631

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1131 AM CDT Sat Apr 25 2026

Valid 251630Z - 261200Z

...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF CENTRAL/EASTERN OKLAHOMA AND FAR NORTH TEXAS...

...SUMMARY...
Severe thunderstorms with very large to giant hail (2 to 4+ inches
in diameter), tornadoes, and scattered damaging winds are expected
late this afternoon through tonight across parts of the southern
Plains and ArkLaTex. A couple of strong tornadoes are possible.

...Southern Plains and ArkLaTex...
While stratus remains semi-prevalent this morning along/north of the near-stationary front, strong to locally extreme instability (MLCAPE
2500-4000+ J/kg) is expected to develop along/east of the dryline in
Texas and Red River-vicinity triple point, and to the south of slow-northward-shifting warm front in Oklahoma by peak afternoon
heating. The presence of seasonably cool temperatures aloft and
7.5-8.5 C/km mid-level lapse rates will also support this very
unstable thermodynamic environment. While large-scale ascent
associated with the ejecting mid-level shortwave trough is not
expected to be overly robust, the arrival of a shortwave
trough/mid-level speed max will be favorably timed atop the warm
sector. At least widely scattered thunderstorm initiation is
expected by mid/late afternoon to early evening (around 20-23Z),
especially near the warm front/dryline intersection and a bit north
across south-central/east-central Oklahoma.

40-50 kt of generally westerly effective bulk shear will support
intense supercells, with multiple right/left splits expected. This
activity will quickly intensify shortly after convective initiation,
and very large to giant hail appears likely (2-4+ inches in
diameter). The potential exists for multiple intense supercells to
track east-southeastward along/near the warm front. A conditional
risk for supercells remains apparent farther south along the length
of the dryline in TX, although confidence in convective initiation
remains low, but at least isolated but intense deep convective
development is plausible, especially in closer proximity to the
surface triple point across North Texas.

Modest southerly low-level winds (around 20-30 kt at 850 mb) will be
present through this evening across the southern Plains. Locally
enhanced 0-1 km SRH will exist near the warm front with backed
near-surface winds. This will support a threat for tornadoes with
any right-split supercells that remain surface based. A slight
increase in the low-level jet this evening and presence of very
strong to locally extreme buoyancy also suggests some threat for a
few EF-2+ tornadoes. With time this evening, convection may
grow upscale and pose a threat for scattered severe/damaging winds
as storm clusters move southeastward across the Red River toward and
across the ArkLaTex.

...Central Plains including Kansas/Nebraska...
Farther north, instability and low-level moisture is expected to
remain weaker/more limited. But, some supercells/small clusters are
expected to develop this afternoon and move east-northeastward given
sufficient deep-layer shear for updraft organization. Isolated to
scattered severe hail and damaging winds should be the main threat
with this activity through mid-evening before eventually weakening.

...Lower Mississippi Valley/Middle Gulf Coast...
Strong to locally severe storms may redevelop later today as outflow
modifies in the wake of the early morning MCS, with the potential
that additional storms, potentially in the form of another MCS,
approach the region from the northwest late tonight.

..Guyer/Barnes.. 04/25/2026

$$

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ACUS01 KWNS 251950
SWODY1
SPC AC 251948

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0248 PM CDT Sat Apr 25 2026

Valid 252000Z - 261200Z

...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
CENTRAL AND SOUTHEASTERN OKLAHOMA INTO FAR NORTHERN TEXAS...

...SUMMARY...
Severe thunderstorms with very large to giant hail (2 to 4+ inches
in diameter), tornadoes (some EF2+), and scattered damaging winds
are expected late this afternoon through tonight across parts of the
southern Plains and ArkLaTex.

...20Z Update...
The previous forecast (see below) remains on track. The main
adjustments made to the outlook (albeit minor) were to slightly
extend the moderate risk-driven hail probabilities to the southwest
to align with the current position of the surface boundary. The
latest high-resolution guidance consensus has consistently depicted
some of the most robust storms to form and anchor along this
boundary. With current mesoanalysis already showing 4000+ J/kg
MLCAPE colocated across far south-central OK, the current thinking
is that intense supercells traversing this boundary will produce
severe hail in the 3-4 inch range, and a couple of stones above 4
inches in diameter cannot be completely ruled out. Tornadoes may
also occur, with the best chance of a strong to intense tornado
being with a boundary-anchoring supercell that can remain discrete
and dominant.

..Squitieri.. 04/25/2026

.PREV DISCUSSION... /ISSUED 1131 AM CDT Sat Apr 25 2026/

...Southern Plains and ArkLaTex...
While stratus remains semi-prevalent this morning along/north of the near-stationary front, strong to locally extreme instability (MLCAPE
2500-4000+ J/kg) is expected to develop along/east of the dryline in
Texas and Red River-vicinity triple point, and to the south of slow-northward-shifting warm front in Oklahoma by peak afternoon
heating. The presence of seasonably cool temperatures aloft and
7.5-8.5 C/km mid-level lapse rates will also support this very
unstable thermodynamic environment. While large-scale ascent
associated with the ejecting mid-level shortwave trough is not
expected to be overly robust, the arrival of a shortwave
trough/mid-level speed max will be favorably timed atop the warm
sector. At least widely scattered thunderstorm initiation is
expected by mid/late afternoon to early evening (around 20-23Z),
especially near the warm front/dryline intersection and a bit north
across south-central/east-central Oklahoma.

40-50 kt of generally westerly effective bulk shear will support
intense supercells, with multiple right/left splits expected. This
activity will quickly intensify shortly after convective initiation,
and very large to giant hail appears likely (2-4+ inches in
diameter). The potential exists for multiple intense supercells to
track east-southeastward along/near the warm front. A conditional
risk for supercells remains apparent farther south along the length
of the dryline in TX, although confidence in convective initiation
remains low, but at least isolated but intense deep convective
development is plausible, especially in closer proximity to the
surface triple point across North Texas.

Modest southerly low-level winds (around 20-30 kt at 850 mb) will be
present through this evening across the southern Plains. Locally
enhanced 0-1 km SRH will exist near the warm front with backed
near-surface winds. This will support a threat for tornadoes with
any right-split supercells that remain surface based. A slight
increase in the low-level jet this evening and presence of very
strong to locally extreme buoyancy also suggests some threat for a
few EF-2+ tornadoes. With time this evening, convection may
grow upscale and pose a threat for scattered severe/damaging winds
as storm clusters move southeastward across the Red River toward and
across the ArkLaTex.

...Central Plains including Kansas/Nebraska...
Farther north, instability and low-level moisture is expected to
remain weaker/more limited. But, some supercells/small clusters are
expected to develop this afternoon and move east-northeastward given
sufficient deep-layer shear for updraft organization. Isolated to
scattered severe hail and damaging winds should be the main threat
with this activity through mid-evening before eventually weakening.

...Lower Mississippi Valley/Middle Gulf Coast...
Strong to locally severe storms may redevelop later today as outflow
modifies in the wake of the early morning MCS, with the potential
that additional storms, potentially in the form of another MCS,
approach the region from the northwest late tonight.

$$

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ACUS01 KWNS 260101
SWODY1
SPC AC 260100

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0800 PM CDT Sat Apr 25 2026

Valid 260100Z - 261200Z

...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
SOUTHEAST OKLAHOMA AND FAR NORTHEAST TEXAS...

...SUMMARY...
Severe thunderstorms with a potential for large to very large,
tornadoes and severe wind gust will continue this evening into
tonight across parts of the southern Plains and Ark-La-Tex.
Additional severe storms with hail and isolated severe gusts will be
possible in parts of the central Plains.

...Southern Plains/Ark-La-Tex...
A low-amplitude mid-level shortwave trough is evident on water vapor
imagery from east-central Kansas southward into west-central
Oklahoma. At the surface, a moist airmass is located over the
eastern part of the southern Plains into the Ark-La-Tex, where
surface dewpoints are in the mid 60s to the mid 70s F. The RAP shows
strong instability across north Texas and southern Oklahoma, with
MLCAPE in the 3000 to 4000 J/kg range. Scattered severe storms are
ongoing near an instability maximum that is near the Red River north
of the Dallas/Fort Worth Metroplex. The RAP is also showing very
steep mid-level lapse rates over southern Oklahoma and far north
Texas. 700-500 mb lapse rates are estimated to be in the 7.5 to 8
C/km range. This will be favorable for large to very large hail.
Hailstones of 2 to 3 inches in diameter will be possible with the
more intense supercells.

In addition, a low-level jet is analyzed from northeast Texas into
eastern Oklahoma. The low-level jet has not strengthened as much as
was originally forecast, but is still expected to gradually ramp up
over the next few hours. This will increase low-level shear
maintaining a tornado threat. The RAP still increases 0-3 km
storm-relative helicity into the 350 to 400 m2/s2 range within a
couple of hours, suggesting that a potential for strong tornadoes
will continue. A wind-damage threat is also expected to be
maintained this evening into the early overnight period, as a severe
convective cluster moves southeastward toward the Ark-La-Tex.

Concerning the placement of the Moderate, it appears that severe
threat coverage will be more limited north of I-40. For this reason,
the northern extent of the Moderate Risk area has been trimmed.

...Central Plains...
Water vapor currently shows a subtle shortwave trough moving into
the mid Missouri Valley and another one moving into the central High
Plains. At the surface, a moist airmass is located from central and
eastern Kansas into far southeast Nebraska, where scattered
thunderstorms are ongoing. Across this area at mid-levels, flow is
generally from west to southwest at 30 to 40 knots. This is creating
sufficient deep-layer shear for organized severe storms. Steep
mid-level lapse rates will be favorable for isolated large hail.
Severe wind gusts will also be possible.

..Broyles.. 04/26/2026

$$

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ACUS01 KWNS 260533
SWODY1
SPC AC 260532

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1232 AM CDT Sun Apr 26 2026

Valid 261200Z - 271200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE CENTRAL PLAINS...

...SUMMARY...
Scattered severe storms with large to very hail, damaging wind gusts
and tornadoes are expected this afternoon and evening across parts
of the central and southern Plains. Strong tornadoes and hailstones
greater than 2 inches in diameter will be possible. Hail and
isolated severe gusts will also be possible in parts of the
Ark-La-Tex and lower Mississippi Valley.

...Southern and Central Plains...
A vigorous mid-level trough will eject northeastward toward the
southern and central Rockies this afternoon into tonight, as an
associated mid-level jet translates east-northeastward through the
Desert Southwest. The exit region of the mid-level jet will
overspread the central Plains by this evening providing lift and
strong deep-layer shear, favorable for severe storms. At the
surface, a lee trough will deepen over the southern and central High
Plains, as moisture advects northward from Oklahoma into Kansas.
Throughout most of the day, large-scale ascent will be limited over
the moist sector. Isolated thunderstorms with hail and severe gusts
will be possible in areas with maximized low-level convergence and
strong instability. Convective coverage will likely increase during
the evening as the mid-level jet max approaches, and as a 40 to 50
knot low-level jet strengthens. By mid to late evening and into the
overnight period, scattered severe storms will be likely in parts of
the central Plains and Ozarks, with isolated storms possible in the
southern Plains.

Model forecasts suggest that a pocket of strong instability will be
in place over Oklahoma early this evening, but that a capping
inversion will exist over much of the moist sector. RAP forecast
soundings at Salina, Kansas gradually erode the capping inversion
during the evening as low-level moisture increases. By late evening
in central Kansas, MUCAPE is forecast to be in the 4500 to 5000 J/kg
range with 0-6 km shear near 50 knots. 700-500 mb lapse rates are
forecast to be very steep and could exceed 8 C/km. This should be
favorable for supercells with large to very large hail. Hailstones
greater than 2 inches in diameter will be possible. Although the
storms will likely be elevated during much of the evening, some
cells could become surface-based in the mid to late evening or early
overnight period. Once this occurs, a tornado threat should develop.
The more intense supercells could produce a strong tornado or two. A wind-damage threat will also be possible.

Further south into parts of Oklahoma, limited large-scale ascent
will make initiation difficult along the dryline. If a storm can
become established during the late afternoon or early to mid
evening, extreme instability (MLCAPE near 5000 J/kg) and steep
mid-level lapse rates near 8 C/Km will be very favorable for large
to very large hail. 0-3 km storm-relative helicity around 250 m2/s2
would also support a tornado threat.

...Ark-La-Tex/Lower Mississippi Valley...
The eastern edge of a moist and unstable airmass will be located in
the lower Mississippi Valley today. Although large-scale ascent will
be weak due to the presence of a mid-level ridge, isolated
convective initiation will be possible in areas that locally heat up
the most. Cells that can strengthen in the late afternoon and early
evening could produce isolated severe gusts and hail.

...Central and Southwest Texas...
The western edge of an extremely unstable airmass will be located
from central Texas into southwest Texas this afternoon. Isolated
thunderstorm initiation will be possible just to the east of a
dryline, as low-level convergence increases late this afternoon. The
extreme instability (MLCAPE of 4000 to 5000 J/kg) with moderate
deep-layer shear and steep mid-level lapse rates would be favorable
for isolated large hail and strong wind gusts.

..Broyles/Moore.. 04/26/2026

$$

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ACUS01 KWNS 261257
SWODY1
SPC AC 261256

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0756 AM CDT Sun Apr 26 2026

Valid 261300Z - 271200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTHERN/CENTRAL PLAINS...

...SUMMARY...
Scattered severe thunderstorms with large to very hail, damaging
winds and tornadoes are expected this afternoon through tonight
across parts of the southern/central Plains. A couple of strong
tornadoes and hailstones up to 2-3 inches in diameter are possible.

...Southern/Central Plains to the Mid Mississippi Valley...
Fairly substantial changes have been made to the outlook based on
latest observational and guidance trends. Namely, the Enhanced Risk
has been expanded into northern OK to account for the potential of
both surface-based supercells this afternoon, and elevated
supercells this evening/tonight. The Slight Risk has been expanded
southward into north-central TX for a somewhat more
conditional/uncertain supercell threat. The eastern extent of severe probabilities have also been expanded in MO to account for a
potential cluster producing severe/damaging winds occurring late
tonight into early Monday morning.

A weak lead mid-level vorticity maximum over the central High Plains
this morning should continue to aid elevated thunderstorm
development across KS through the afternoon. Increasing MUCAPE with
persistent low-level warm/moist advection and steepening mid-level
lapse rates combined with strong deep-layer shear will support
organized updrafts, including the potential for supercells. This
convection will probably tend to remain elevated to the north of a
front as it spreads east-northeastward over the central Plains, but
scattered large hail may occur given the overall favorable
environment. Isolated 2+ inch diameter hail also appears possible
with the strongest cores. Eventually, this activity may pose a
greater threat for damaging winds across eastern KS into western MO
by late afternoon/early evening, if it can become truly surface
based.

A more notable mid-level shortwave trough is expected to eject
northeastward across the Southwest and southern/central High Plans
today, accompanied by a 50-60 kt southwesterly mid-level jet. Weak
lee cyclogenesis is forecast to occur across the southeast
CO/northeast NM vicinity in response, with the surface low
developing into the OK Panhandle and southwest KS by this evening.
Strong to locally extreme instability is once again forecast to
develop to the east of a sharpening dryline across western/central
OK as daytime heating of a moist airmass occurs. There is still a
fair amount of uncertainty with the placement of an effective warm
front by late afternoon/early evening, but current expectations are
for this boundary to be draped somewhere near north-central OK by
peak afternoon heating. The surface triple point may serve as a
focus for convective initiation today, although better large-scale
ascent associated with the mid-level shortwave trough overspreading
the warm sector will be delayed until this evening and past peak
diurnal heating.

Greater than average uncertainty exists regarding the potential for surface-based convective initiation today in OK/north TX. Still, it
appears possible that multiple supercells may develop with gradual
erosion of lingering MLCIN and weak ascent preceding the ejecting
shortwave trough. Any supercells that can root and ingest the ample
low-level moisture will be capable of producing very large hail
(2-3+ inches in diameter) given a overall rather favorable
environment. The tornado potential is less clear through the day,
but a southerly low-level jet will quickly strengthen this evening
and aid curved/elongated hodographs with strong effective SRH. A
somewhat conditional/uncertain threat for a couple of strong
tornadoes remains apparent, especially if any supercells that can
form this afternoon persist into the evening.

Additional, somewhat elevated supercells may form this evening into
tonight along/north of the warm front from northwest OK near the
triple point into KS. This activity will also pose a threat for
large to very large hail. Some guidance suggests a cluster
eventually evolves from this convection across eastern KS into MO
late tonight/early Monday morning. If this occurs, then a greater
threat for severe/damaging winds would exist.

Farther south into TX, the forcing for ascent will remain
weak/nebulous along the dryline. Still, some potential for a few
supercells is apparent across north-central TX where the greatest
heating and minimal MLCIN is forecast to exist. Large to very large
hail should be the main threat with any splitting supercells that
can develop this afternoon along/east of the dryline and be
sustained.

...ArkLaTex/Lower Mississippi Valley/Central Gulf Coast...
A small cluster will continue tracking southeastward this morning
from southern MS to the central Gulf Coast. With sufficient
low-level moisture and instability in place ahead of this
convection, isolated damaging winds may occur. A pair of supercells
across northeast TX have fluctuated in intensity over the past
couple of hours. The potential for additional thunderstorms to form
on the western flank/outflow of this morning convection remains
unclear given weak large-scale forcing and the low-level jet
forecast to weaken further through the morning. If any additional
convection can form, it would pose an isolated severe hail and
damaging wind threat.

..Gleason/Thompson.. 04/26/2026

$$

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ACUS01 KWNS 261655
SWODY1
SPC AC 261654

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1154 AM CDT Sun Apr 26 2026

Valid 261630Z - 271200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS KANSAS
AND NORTHERN OKLAHOMA TO WESTERN MISSOURI...

...SUMMARY...
Scattered severe thunderstorms with large to very large hail,
damaging winds and tornadoes are expected this afternoon through
tonight across parts of the southern/central Plains to Lower
Missouri Valley. A couple of strong tornadoes and hailstones up to
2-3 inches in diameter are possible.

...Southern/Central Plains to the Mid Mississippi Valley...
Appreciable severe potential is still readily apparent especially
later this afternoon into tonight, although sub-regional details
remain quite complex, particularly regarding the southern extent of
deep convective initiation southward along the dryline.

A weak lead mid-level vorticity maximum over the central High Plains
early today will continue to aid elevated thunderstorm development
across Kansas through the afternoon. See Mesoscale Discussion 547
for short-term details. Increasing MUCAPE with persistent low-level
warm/moist advection and steepening mid-level
lapse rates combined with strong deep-layer shear will support
organized updrafts, including the potential for supercells. This
convection will probably tend to remain elevated to the north of a
front as it spreads east-northeastward over the central Plains, but
scattered large hail may occur given the overall favorable
environment. Isolated 2+ inch diameter hail also appears possible
with the strongest cores. Eventually, this activity may pose a
greater threat for damaging winds across eastern Kansas into western
Missouri by late afternoon/early evening.

A more notable mid-level shortwave trough is expected to eject
northeastward across the Southwest and southern/central High Plans
today, accompanied by a 50-60 kt southwesterly mid-level jet. Weak
lee cyclogenesis is forecast to occur across the southeast
Colorado/northeast New Mexico vicinity in response, with the surface
low developing into the Oklahoma Panhandle and southwest Kansas by
this evening. Strong to locally extreme instability is forecast to
develop east of a sharpening dryline across western/central Oklahoma
as daytime heating of a moist airmass occurs. There is still a fair
amount of uncertainty with the placement of an effective warm front
by late afternoon/early evening, but current expectations are for
this boundary to be draped somewhere near north-central Oklahoma by
peak afternoon heating. The surface triple point may serve as a
focus for convective initiation later today into this evening,
although better large-scale ascent associated with the mid-level
shortwave trough overspreading the warm sector will be delayed until
this evening and past peak diurnal heating.

Greater than average uncertainty exists regarding the potential for surface-based convective initiation today in Oklahoma/north Texas,
but the volatile environment and ample conditional-type potential is concerning. It appears possible that multiple supercells may develop
with gradual erosion of lingering MLCIN and weak ascent preceding
the ejecting shortwave trough. Any supercells that can root and
ingest the ample low-level moisture will be capable of producing
very large hail (2-3+ inches in diameter) given a overall rather
favorable environment. The tornado potential is less clear through
the day, but a southerly low-level jet will quickly strengthen this
evening and aid curved/elongated hodographs with strong effective
SRH. A somewhat conditional/uncertain threat for a couple of strong
tornadoes remains apparent, especially if any supercells that can
form this afternoon persist into the evening.

Additional, somewhat elevated supercells may form this evening into
tonight along/north of the warm front from northern Oklahoma near
the triple point into Kansas. This activity will also pose a threat
for large to very large hail and possibly an increasing
tornado/damaging wind risk.

Farther south into Texas, the forcing for ascent will remain
weak/nebulous along the dryline. Still, some potential for a few
supercells is apparent across north-central Texas where the greatest
heating and minimal MLCIN is forecast to exist. Large to very large
hail should be the main threat with any splitting supercells that
can develop this afternoon along/east of the dryline and be
sustained.

..Guyer/Barnes.. 04/26/2026

$$

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ACUS01 KWNS 262000
SWODY1
SPC AC 261958

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0258 PM CDT Sun Apr 26 2026

Valid 262000Z - 271200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER MUCH OF
CENTRAL AND EASTERN KANSAS INTO FAR NORTHERN OKLAHOMA AND FAR
WESTERN MISSOURI...

...SUMMARY...
Scattered severe thunderstorms with large to very large hail,
damaging winds and tornadoes are expected this afternoon through
tonight across parts of the southern/central Plains to Lower
Missouri Valley. A couple of strong tornadoes and hailstones up to
2-3 inches in diameter are possible.

...20Z Update...
The forecast (see below) remains generally on track. The main
changes made to this outlook were to expand severe probabilities
farther to the east to account for an uptick in severe potential
later tonight, as depicted by some of the latest high-resolution
guidance.

Overall, uncertainties remain regarding precisely where the
strongest storms are going to occur. OK Mesonet data over the past
few hours have depicted some lowering of dewpoints in west-central
OK, with a slightly diminished CU field noted. However, several
guidance members depict supercellular development in the 02-06Z
period over northern OK, likely in part to the strengthening of a
low-level jet. Given impressive shear profiles and 8.5-9 C/km
mid-level lapse rates expected in this region overnight, it is
plausible that the strongest storms for the remainder of the period
(to 12Z Monday morning) may occur here, with 2+ inch diameter hail
and perhaps strong tornadoes. The primary uncertainty for
introducing higher tornado probabilities over northern OK is the
possible late storm initiation and associated boundary layer
stabilization, which may dampen the robustness of tornado production
with these storms.

Visible satellite imagery depicts more agitated CU centered over
Baylor County, TX, which may hint at locally higher/less conditional
severe threat across far north-central TX later this afternoon and
evening. However, synoptic forcing is weak, and if storms form, they
will likely be sparse, precluding the addition of higher severe
probabilities in this region at this time.

..Squitieri.. 04/26/2026

.PREV DISCUSSION... /ISSUED 1154 AM CDT Sun Apr 26 2026/

...Southern/Central Plains to the Mid Mississippi Valley...
Appreciable severe potential is still readily apparent especially
later this afternoon into tonight, although sub-regional details
remain quite complex, particularly regarding the southern extent of
deep convective initiation southward along the dryline.

A weak lead mid-level vorticity maximum over the central High Plains
early today will continue to aid elevated thunderstorm development
across Kansas through the afternoon. See Mesoscale Discussion 547
for short-term details. Increasing MUCAPE with persistent low-level
warm/moist advection and steepening mid-level
lapse rates combined with strong deep-layer shear will support
organized updrafts, including the potential for supercells. This
convection will probably tend to remain elevated to the north of a
front as it spreads east-northeastward over the central Plains, but
scattered large hail may occur given the overall favorable
environment. Isolated 2+ inch diameter hail also appears possible
with the strongest cores. Eventually, this activity may pose a
greater threat for damaging winds across eastern Kansas into western
Missouri by late afternoon/early evening.

A more notable mid-level shortwave trough is expected to eject
northeastward across the Southwest and southern/central High Plans
today, accompanied by a 50-60 kt southwesterly mid-level jet. Weak
lee cyclogenesis is forecast to occur across the southeast
Colorado/northeast New Mexico vicinity in response, with the surface
low developing into the Oklahoma Panhandle and southwest Kansas by
this evening. Strong to locally extreme instability is forecast to
develop east of a sharpening dryline across western/central Oklahoma
as daytime heating of a moist airmass occurs. There is still a fair
amount of uncertainty with the placement of an effective warm front
by late afternoon/early evening, but current expectations are for
this boundary to be draped somewhere near north-central Oklahoma by
peak afternoon heating. The surface triple point may serve as a
focus for convective initiation later today into this evening,
although better large-scale ascent associated with the mid-level
shortwave trough overspreading the warm sector will be delayed until
this evening and past peak diurnal heating.

Greater than average uncertainty exists regarding the potential for surface-based convective initiation today in Oklahoma/north Texas,
but the volatile environment and ample conditional-type potential is concerning. It appears possible that multiple supercells may develop
with gradual erosion of lingering MLCIN and weak ascent preceding
the ejecting shortwave trough. Any supercells that can root and
ingest the ample low-level moisture will be capable of producing
very large hail (2-3+ inches in diameter) given a overall rather
favorable environment. The tornado potential is less clear through
the day, but a southerly low-level jet will quickly strengthen this
evening and aid curved/elongated hodographs with strong effective
SRH. A somewhat conditional/uncertain threat for a couple of strong
tornadoes remains apparent, especially if any supercells that can
form this afternoon persist into the evening.

Additional, somewhat elevated supercells may form this evening into
tonight along/north of the warm front from northern Oklahoma near
the triple point into Kansas. This activity will also pose a threat
for large to very large hail and possibly an increasing
tornado/damaging wind risk.

Farther south into Texas, the forcing for ascent will remain
weak/nebulous along the dryline. Still, some potential for a few
supercells is apparent across north-central Texas where the greatest
heating and minimal MLCIN is forecast to exist. Large to very large
hail should be the main threat with any splitting supercells that
can develop this afternoon along/east of the dryline and be
sustained.

$$

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ACUS01 KWNS 270106
SWODY1
SPC AC 270105

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0805 PM CDT Sun Apr 26 2026

Valid 270100Z - 271200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS CENTRAL/EASTERN KANSAS...NORTHERN OKLAHOMA...FAR WESTERN MISSOURI...

...SUMMARY...
Scattered severe thunderstorms with large to very large hail,
damaging winds and tornadoes are expected tonight across parts of
the southern/central Plains to Lower Missouri Valley. A couple of
strong tornadoes and hailstones up to 2-3 inches in diameter are
possible.

...01Z Update...
A prominent shortwave trough now nearing the Colorado/Kansas border
is promoting elevated convection ahead of it. An 8.2 C/km mid-level
lapse rate was sampled on the 00Z DDC sounding this evening. These
steep lapse rates should shift eastward along with the shortwave
trough. Additional, stronger convection remains possible in parts of central/eastern Kansas into northern Oklahoma. Earlier convection
has complicated the low-level thermodynamic environment, though
large hail and damaging winds are possible with organized cells and
linear structures. The tornado threat through the evening is
somewhat less clear, but a deepening surface low should advect
richer moisture northward. Depending on storm mode and low-level
stability, tornadoes remain possible in parts of northern Oklahoma
and south-central Kansas later this evening. In the short term, the
greatest threat for a strong tornado is in southeast Kansas. In
Oklahoma into North Texas, the dryline is surging westward. This
area will become increasingly removed from large-scale ascent. An
isolated storm or two remain possible at least trough mid-evening.
Lastly, convection in Missouri and southeast Kansas will eventually
grow upscale. A buoyancy gradient within the Mid-South region may
serve as a focus for continued southeast movement through the
evening. Marginal wind and hail are possible with this activity.

..Wendt.. 04/27/2026

$$

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ACUS01 KWNS 270601
SWODY1
SPC AC 270600

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0100 AM CDT Mon Apr 27 2026

Valid 271200Z - 281200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE MID-MISSISSIPPI VALLEY INTO THE LOWER OHIO VALLEY AND PARTS OF THE
MID-SOUTH...

...SUMMARY...
Widespread strong to severe thunderstorm development appears
probable across the middle Mississippi into lower Ohio Valleys this
afternoon through this evening, accompanied by potential for a few
strong tornadoes, damaging wind gusts and large hail.

...Synopsis...
Water vapor imagery shows a prominent shortwave trough promoting
elevated strong to severe convection across central and eastern
Kansas. This activity is expected to move north and eastward through Iowa/Missouri/Wisconsin/northern Illinois into daybreak and perhaps
part of the afternoon for some areas. The outflow from this
convection should act to limit the northern extent of greater
destabilization during the afternoon and thus the greatest severe
threat. A surface low will track northeastward along the parent
shortwave. Though this low has trended downward in intensity in
recent model runs, strong low-level wind fields are expected within
the warm sector throughout the day and into the evening. Areas of
pre-frontal convergence and a cold front will be the focus for
convective development along with more strongly forced convection
tied to the shortwave trough. The front will be draped south and
westward into the Ozarks and the southern Plains.

...Mid-Mississippi Valley/Lower Ohio Valley...
As mentioned, surface based buoyancy will be limited by early day
activity. The current expectation is for parts of central/eastern
Missouri into central/southern Illinois and western Kentucky to see
greater destabilization. There is activity ongoing within central
Missouri early this morning that may have some impact, however. This
is the source of greatest uncertainty for these regions. The
kinematic environment will certainly be favorable for supercells.
The moderate to strong 850 mb jet will also lead to potential for
several tornadoes, some of which could be strong. Lapse rates at
mid-levels will be rather steep. Large to very-large hail potential
is evident given the long hodographs. Some upscale growth into one
or more linear segments is expected to occur. This will increase
the threat for damaging winds. An increase in tornado probabilities
was considered. Given the questions regarding early day convection
and where favorable convergence zones/outflow boundaries might be
located reduces confidence. Convective trends into daybreak will
need to be closely monitored.

...Mid-South...
Models indicate potential for supercells along the cold front and
even potentially ahead of it. Forcing for ascent will be weaker, but
this may help to keep activity cellular longer. Some of this
activity could develop after 00Z. Mid-level lapse rates are expected
to be steep enough and mid-level flow strong enough to support large
to potentially very large hail and damaging winds. The tornado
threat will likely be lower given the time of day and tendency for
storms to be at least slightly elevated.

...Upper Midwest...
Observational and model trends suggest destabilization will be more
limited on account of convection at daybreak and beyond. Even so,
strong low-level and effective shear will still allow storms to be
organized and capable of large hail, damaging winds and a couple
tornadoes. There will be potential for both convection at daybreak
and also during the afternoon. The greatest potential for afternoon
supercells would be in parts of eastern Iowa along with the surface
low and colder air aloft.

...Western/central Texas...
As moisture returns westward during the evening, some model guidance
suggest convection might try to develop along the retreating
dryline. Buoyancy and shear would support a threat for large hail
and perhaps severe winds. However, mid-level ascent will be very
weak and models generally do not sustain these convective attempts.
Severe probabilities may be needed if confidence in development
increases.

..Wendt/Moore.. 04/27/2026

$$

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ACUS01 KWNS 271247
SWODY1
SPC AC 271245

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0745 AM CDT Mon Apr 27 2026

Valid 271300Z - 281200Z

...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
MISSOURI INTO ILLINOIS...

...SUMMARY...
Numerous severe thunderstorms are expected from the mid
Mississippi/lower Ohio Valleys into the Mid-South through this
evening, with a threat for multiple strong to intense tornadoes
(EF-3+), widespread severe/damaging wind gusts, and scattered large
to very large hail.

...Mid Mississippi Valley/Midwest into the Mid-South/Lower
Mississippi Valley...
An active severe weather day is forecast for much of the mid MS
Valley/lower OH Valleys into the Mid-South. Ongoing thunderstorms
this morning complicate the overall scenario to some extent, but a
very favorable corridor for intense supercells and strong tornadoes
is apparent this afternoon/evening across parts of MO into IL, where
a Moderate Risk (Level 4 of 5) has been introduced.

Elevated supercells with mainly a hail threat should persist for at
least a couple more hours this morning across the mid MS Valley as
strong low-level warm advection aids in continued influx of
sufficient MUCAPE amid strong deep-layer shear. Multiple
clusters/embedded supercells are also ongoing this morning across
western into northern MO. This activity should pose a greater threat
for scattered severe/damaging winds, along with some hail risk. The
tornado threat in the short term (this morning) remains unclear, but
it should eventually increase as the boundary-layer across central
MO continues to gradually destabilize/moisten. See Mesoscale
Discussion 565 for more details on the near-term severe risk with
these ongoing thunderstorms.

Current expectations are for the greatest severe risk to focus south
of these morning thunderstorms. A mid/upper-level trough will eject northeastward from the northern/central Plains into the Midwest and
mid MS Valley through the period. Low-level mass response will
encourage the primary surface low to consolidate across MN/WI by
this evening, with an effective warm front delineated by the morning convection. Aided by daytime heating and steep mid-level lapse
rates, a moderately to strongly unstable airmass is expected to be
in place by early to mid afternoon across much of central
MO/southern IL southward into the Mid-South and lower MS Valley.

Strengthening west-southwesterly flow aloft associated with a 50-70
kt mid-level jet will overspread much of the warm sector by peak
heating, and a 35-45 kt south-southwesterly low-level jet will both
provide ample low-level and deep-layer shear to support supercells.
Initially discrete surface-based development appears likely to occur
by 19-21Z across the mid MS Valley/Mid-South ahead of the surface
cold front, and perhaps along weak low-level confluence zones in the
open warm sector.

These supercells will exist in a very favorable environment for
tornadoes through the afternoon and evening, and multiple strong to
intense tornadoes (EF-2/3+) appear likely, especially from parts of
MO into IL along/near the effective front. This strong tornado
threat may also extend farther south into AR/TN, but confidence is
somewhat lower with southward extent due to weaker large-scale
forcing. Large to very large hail (2-3 inches in diameter) may also
occur with any sustained supercells.

By early evening, convection will probably tend to consolidate into
clusters capable of producing numerous to widespread damaging winds
from the mid MS Valley eastward into the lower OH Valley, before
eventually weakening tonight as instability gradually decreases. A
threat for QLCS and embedded supercell tornadoes will persist
through much of the evening and early overnight hours as well given
strong low-level shear forecast.

To the north of the ongoing morning convection across IA/northern
IL/WI, a lesser (but non-zero) severe risk is forecast. This region
will have less instability this afternoon, but strong shear. Have
maintained the Marginal/Slight Risks for the possibility of isolated
to locally scattered hail/damaging winds, and perhaps a couple of
tornadoes.

...ArkLaTex into Texas...
Confidence in sustained convection occurring from the ArkLaTex
southward into TX is lower compared to locations farther north. But,
strong heating ahead of a surface dryline could support isolated to
scattered supercells capable of producing large to very large hail
and occasional damaging winds. Increasing low-level warm/moist
advection tonight could foster additional robust thunderstorms along
the retreating dryline and eventually the southward-moving cold
front. Severe probabilities have been expanded across these regions
to account for this potential.

..Gleason/Thornton.. 04/27/2026

$$

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ACUS01 KWNS 271651
SWODY1
SPC AC 271650

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1150 AM CDT Mon Apr 27 2026

Valid 271630Z - 281200Z

...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS
EAST/SOUTHEAST MISSOURI...SOUTHERN ILLINOIS...WESTERN KENTUCKY...AND
NORTHWEST TENNESSEE...

...SUMMARY...
Numerous severe thunderstorms are expected from the mid
Mississippi/lower Ohio Valleys into the Mid-South through this
evening, with a threat for multiple strong to intense tornadoes
(EF3+), widespread severe/damaging wind gusts, and scattered large
to very large hail.

...Mid Mississippi Valley/Midwest into the Mid-South/Lower
Mississippi Valley...
Forecast scenario largely unchanged in that a very active severe-weather/tornado day is expected regionally, especially into
late afternoon and this evening. Initially, a relatively long-lived
linear cluster of convection persists at late morning across east-central/south-central Illinois, with additional initially
elevated storms on its eastern/southern periphery, moving from
eastern Illinois into Indiana, with severe hail and damaging winds
persisting as early day hazards.

Over time, air mass will continue to moisten and rapidly destabilize along/south of the MCS-associated outflow from central Missouri into south-central Illinois. A mid/upper-level trough will eject
northeastward from the northern/central Plains into the Midwest and
middle Mississippi Valley through the period. Low-level mass
response will encourage the primary surface low to consolidate
across Minnesota/Wisconsin by this evening, with a warm front
effectively delineated by the morning convection.

Strengthening west-southwesterly flow aloft associated with a 50-70
kt mid-level jet will overspread much of the warm sector by peak
heating, and a 35-45 kt south-southwesterly low-level jet will both
provide ample low-level and deep-layer shear to support supercells.
Initially discrete surface-based development appears likely to occur
into mid-afternoon across the mid Mississippi Valley/Mid-South ahead
of the surface cold front, and perhaps along weak low-level
confluence zones in the open warm sector including generally near
the confluence of the Mississippi/Ohio Rivers southward into the
Mid-South.

These supercells will exist in a very favorable environment for
tornadoes through the afternoon and evening, and multiple strong to
intense tornadoes (EF2/3+) appear likely, especially from parts of
Missouri into Illinois along/near the effective front. This strong
tornado potential will also likely extend farther south within the
warm sector into the Mid-South.

By early evening, convection will probably tend to consolidate into
clusters of supercells and then more linear segments with some
increase in damaging wind potential aside from large hail and a
continued multi-mode tornado risk tonight.

...ArkLaTex into Texas...
While storm coverage may trend lesser with southwest extent, the
potential for at least isolated intense storms will exist across the
region. Supercells capable of producing large to very large hail and
occasional damaging winds are expected. Increasing low-level
warm/moist advection tonight could foster additional robust
thunderstorms along the retreating dryline and eventually the
southward-moving cold front.

..Guyer/Weinman.. 04/27/2026

$$

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ACUS01 KWNS 271951
SWODY1
SPC AC 271949

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0249 PM CDT Mon Apr 27 2026

Valid 272000Z - 281200Z

...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS
EAST/SOUTHEAST MISSOURI...SOUTHERN ILLINOIS...WESTERN KENTUCKY...AND
NORTHWEST TENNESSEE...

...SUMMARY...
Numerous severe thunderstorms are expected from the mid
Mississippi/lower Ohio Valleys into the Mid-South through this
evening, with a threat for multiple strong to intense tornadoes
(EF3+), widespread severe/damaging wind gusts, and scattered large
to very large hail.

...20z Update...
Only minor adjustments were made to extend the Marginal Risk back
into southeastern Kansas/northeastern Oklahoma to account for storms
initiating over the last hour.

The Moderate Risk remains unchanged with this update. The morning
MCS is now moving through eastern Illinois/southern Indiana. Further
west in Missouri and western Illinois, modifying remnant outflow
remains near the St. Louis Metro. Cumulus south of this boundary
across southeastern Missouri into southern Illinois, cumulus within
the warm sector is deepening. Increasing MLCAPE/steepening lapse
rates are nosing northward in southern central Missouri and
south-central Illinois.

Just to the west of the Mississippi River, radar shows occasional
attempts at initiation within the open warm sector. While the
details continue to evolve, it likely that a corridor of conditional
threat for strong-intense tornadoes will develop from the Missouri
Bootheel into southern Illinois/western Kentucky. Within this region
strong daytime heating has led to a volatile air mass, with moderate
to strong MLCAPE 2000-3000 J/kg and strong deep layer shear. VAD
profiles frm PAH (Paducah, KY) and LSX (St. Louis, MO) indicate a
rich SRH environment of around 200-300 m2/s2 in the 0-1 km layer. It
is likely that supercells capable of all hazards, including
strong-intense tornadoes, large to very large hail, and damaging
winds. Will develop across this region soon. See MCD571 for
additional information.

The conditional threat for strong tornadoes will extend as far south
as the Arklatex into portions of western Tennessee. Through time,
storm mode will shift to become linear with the southward moving
front, which will bring an increase into the evening of damaging
wind threat. Line embedded tornadoes, some of which may be strong,
will continue to be a threat into the evening.

..Thornton.. 04/27/2026

.PREV DISCUSSION... /ISSUED 1150 AM CDT Mon Apr 27 2026/

...Mid Mississippi Valley/Midwest into the Mid-South/Lower
Mississippi Valley...
Forecast scenario largely unchanged in that a very active severe-weather/tornado day is expected regionally, especially into
late afternoon and this evening. Initially, a relatively long-lived
linear cluster of convection persists at late morning across east-central/south-central Illinois, with additional initially
elevated storms on its eastern/southern periphery, moving from
eastern Illinois into Indiana, with severe hail and damaging winds
persisting as early day hazards.

Over time, air mass will continue to moisten and rapidly destabilize along/south of the MCS-associated outflow from central Missouri into south-central Illinois. A mid/upper-level trough will eject
northeastward from the northern/central Plains into the Midwest and
middle Mississippi Valley through the period. Low-level mass
response will encourage the primary surface low to consolidate
across Minnesota/Wisconsin by this evening, with a warm front
effectively delineated by the morning convection.

Strengthening west-southwesterly flow aloft associated with a 50-70
kt mid-level jet will overspread much of the warm sector by peak
heating, and a 35-45 kt south-southwesterly low-level jet will both
provide ample low-level and deep-layer shear to support supercells.
Initially discrete surface-based development appears likely to occur
into mid-afternoon across the mid Mississippi Valley/Mid-South ahead
of the surface cold front, and perhaps along weak low-level
confluence zones in the open warm sector including generally near
the confluence of the Mississippi/Ohio Rivers southward into the
Mid-South.

These supercells will exist in a very favorable environment for
tornadoes through the afternoon and evening, and multiple strong to
intense tornadoes (EF2/3+) appear likely, especially from parts of
Missouri into Illinois along/near the effective front. This strong
tornado potential will also likely extend farther south within the
warm sector into the Mid-South.

By early evening, convection will probably tend to consolidate into
clusters of supercells and then more linear segments with some
increase in damaging wind potential aside from large hail and a
continued multi-mode tornado risk tonight.

...ArkLaTex into Texas...
While storm coverage may trend lesser with southwest extent, the
potential for at least isolated intense storms will exist across the
region. Supercells capable of producing large to very large hail and
occasional damaging winds are expected. Increasing low-level
warm/moist advection tonight could foster additional robust
thunderstorms along the retreating dryline and eventually the
southward-moving cold front.

$$

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ACUS01 KWNS 280101
SWODY1
SPC AC 280059

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0759 PM CDT Mon Apr 27 2026

Valid 280100Z - 281200Z

...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF SOUTHEASTERN MISSOURI INTO FAR SOUTHERN ILLINOIS AND WESTERN
KENTUCKY...

...SUMMARY...
Severe storms should continue through tonight with a wind and hail
threat. A few tornadoes may still occur, and a couple of strong
tornadoes remain possible.

...Synopsis...
A negatively tilted 500 mb mid-level trough continues to traverse
the Upper Midwest in tandem with a surface low, supporting a surface
cold front to sweep across the Mid-MS Valley. A persistent elongated
convective system has materialized along the cold front, accompanied
by several embedded and preceding supercells. These storms have a
collective history of severe wind and hail, with some stones
reaching the 2-3 inch diameter range.

Upper 60s to low 70s F surface dewpoints, beneath 8+ C/km mid-level
lapse rates, resides ahead of the cold front/storms, yielding over
3000 J/kg MLCAPE in spots. Meanwhile, strong mid-level flow
associated with a speed max is overspreading an intensifying (45+
kt) southwesterly low-level jet, resulting in 50+ kts of effective
bulk shear and large/curved low-level hodographs with 300-500 m2/s2
effective SRH (per 00Z mesoanalysis and regional VADs). Supercells
have failed to organize and produce tornadoes up to this point.
However, storms along/ahead of the cold front will continue to
advance eastward toward the low-level jet/shear axis. Therefore, an
uptick in tornado activity may still occur early tonight, especially
with any discrete, sustained supercells that can develop. Discrete
storms may also be accompanied by severe hail, with severe wind
gusts likely with continued linear storm modes.

..Squitieri.. 04/28/2026

$$

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ACUS01 KWNS 280601
SWODY1
SPC AC 280559

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1259 AM CDT Tue Apr 28 2026

Valid 281200Z - 291200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
NORTHERN TEXAS INTO THE LOWER MISSISSIPPI VALLEY...

...SUMMARY...
Multiple rounds of strong to severe thunderstorms are likely across
parts Texas into the lower Mississippi and Tennessee Valleys this
afternoon and evening. Very large hail, swaths of damaging wind, and
a few tornadoes are possible.

...Synopsis...
A series of mid-level troughs, embedded within a broader
low-amplitude mid-level flow regime, will traverse the central U.S.
today. A surface low and associated cold front will continue to
progress across the OH Valley toward the East Coast during the day.
However, the approach of another mid-level trough over the Ozark
Valley region will encourage either a weak surface low or surface
trough to develop over central TX. This will stall the southward
progression of the surface cold front given appreciable low-level warm-air/moisture advection. Seasonally cold air aloft and
accompanying upper support from multiple embedded mid-level
perturbations will overspread the warm-air advection regime,
supporting several rounds of thunderstorms. Given strong vertical
wind shear over the warm sector, severe storms are likely,
especially over portions of the southern Plains toward the TN
Valley.

...Portions of northern TX into the TN Valley...
A complex severe weather scenario is expected across TX into the TN
Valley through the period, with multiple rounds of severe
thunderstorms likely. The first round of storms is currently
initiating over western TX, and may increase in coverage between
12-18Z across central OK into northern TX as a lead mid-level
impulse traverses a WAA regime. 7-8 C/km mid-level lapse rates amid
50+ kts of effective bulk shear will support elevated multicells
capable of producing severe hail. These storms will progress across
the MS Valley through the day. Some guidance indicates that these
storms may evolve into an MCS by afternoon, accompanied by a
damaging gust threat over the Gulf coast states.

Regardless of the evolution of earlier storms, guidance consensus
depicts adequate clearing behind this initial wave over TX into the
Ozark Valley region. Strong surface heating will encourage surface
temperatures to reach 90 F in some locales, amid 70+ F surface
dewpoints. Given 8-9 C/km mid-level lapse rates, MLCAPE should reach
the 2500-4000 J/kg range by mid to late afternoon. By this time, the
primary mid-level trough will overspread the southern Plains,
promoting enough deep-layer ascent for another round of storms to
initiate. Given 50 kts of effective bulk shear and initially
straight hodographs, supercells are expected, accompanied by a
severe hail threat. The most intense supercells may develop over
northern TX and progress eastward, and will be capable of producing
severe hail as large as 3-4 inches in diameter. Given a lingering
low-level jet (supporting elongated hodographs with some low-level
curvature) over the Sabine River Valley, a few dominant/right-moving
supercells may produce a few tornadoes, though the tornado threat
will be conditional on adequate boundary-layer
mixing/destabilization. Later in the afternoon/early evening, severe hail/isolated tornado producing supercells may merge into an MCS,
accompanied by a severe wind threat across the Lower MS Valley.

...Portions of central into southern TX...
Forcing for ascent will be weak across portions of central into
southwestern TX. Nonetheless, 8-9 C/km mid-level lapse rates will
overspread a well-mixed boundary layer. Tropospheric speed shear
exceeding 40 kts will yield elongated hodographs, so any storm that
can initiate, mature, and sustain itself should be supercellular in
nature, accompanied by a severe hail threat. Any instance of hail
with these storms may include stones exceeding 2 inches in diameter.
Since a second, low-amplitude mid-level impulse will overspread
western and central TX toward the end of the period, isolated
supercell initiation will be possible across portions of central
into southwestern TX late this afternoon into early (12Z) Wednesday
morning.

..Squitieri/Moore.. 04/28/2026

$$

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ACUS01 KWNS 281202
SWODY1
SPC AC 281200

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0700 AM CDT Tue Apr 28 2026

Valid 281300Z - 291200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTHERN PLAINS INTO THE LOWER MISSISSIPPI VALLEY AND
MID-SOUTH...

...SUMMARY...
Multiple rounds of severe thunderstorms will occur across parts of
the southern Plains into the lower Mississippi/Tennessee Valleys and
Southeast through this evening. Very large to giant hail (2-4+
inches), swaths of severe/damaging winds, and a few tornadoes are
all possible.

...Southern Plains into the Lower Mississippi Valley/Southeast...
With large-scale upper troughing anchored over the Plains and
central Canada, an embedded mid-level shortwave trough will eject
eastward across the southern/central Plains to the lower/mid MS
Valleys by this evening. Rich low-level moisture continues to spread
northward from TX into southern OK this morning in tandem with a
low-level jet, and this trend should continue downstream into the
lower MS Valley through the day as a warm front lifts northward to a
weak surface low across the Ozarks. Another surface low will remain
over northwest TX, with a dryline extending southwestward to the Big
Bend region.

A strongly unstable airmass exists across the southern Plains to the
ArkLaTex, along and near a slowly retreating/northward-returning
warm front. Elevated supercells are ongoing across western north TX.
This activity is being aided by lift and strong deep-layer shear
associated with the ejecting mid-level shortwave trough, and
low-level warm/moist advection. Current expectations are for these
supercells to continue posing a threat for mainly large to very
large hail through the rest of the morning as they spread
east-northeastward across north TX/southern OK. But, eventual
clustering and a greater damaging wind threat may materialize into
the afternoon as this convection crosses the front and accesses
greater instability across AR and the Ozarks.

Additional surface-based convective development is forecast near the
triple point in north-central TX towards the ArkLaTex this
afternoon, where extreme instability (4000+ J/kg MLCAPE) and very
strong deep-layer shear (50-60+ kt) will support the potential for
multiple intense supercells. Very large to giant hail (2-4+ inches)
may occur with the strongest supercells given the overall very
favorable environment and presence of steep mid-level lapse rates.
Some tornado threat may also exist with these supercells, even
though low-level shear is not forecast to be overly strong.

Numerous to widespread convection across the Mid-South to southern
Appalachians has generally diminished in intensity this morning. In
its wake, airmass recovery is anticipated today across the lower MS
Valley and Mid-South. A convectively reinforced front/outflow
boundary from the morning thunderstorms should attempt to lift
northward some through the day, with the greater instability
forecast across the lower MS Valley where steep mid-level lapse
rates are in place. Convective evolution across these areas through
the evening remains unclear, but multiple rounds of supercells and
multicell clusters capable of producing large hail, scattered to
numerous damaging winds, and perhaps a few tornadoes appear likely.
Less instability is forecast to the north of the ongoing convection
across the TN Valley, but some airmass recovery and severe threat
still appears possible by late afternoon/early evening.

..Gleason/Jewell.. 04/28/2026

$$

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ACUS01 KWNS 281653
SWODY1
SPC AC 281651

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1151 AM CDT Tue Apr 28 2026

Valid 281630Z - 291200Z

...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS NORTH
TEXAS...

...SUMMARY...
Multiple rounds of severe thunderstorms will occur across parts of
the southern Plains into the lower Mississippi/Tennessee Valleys and
Southeast through this evening. Very large to giant hail (2-4+
inches), swaths of severe/damaging winds, and a few tornadoes are
all possible.

...Southern Plains to Lower Mississippi Valley/Southeast...
Have upgraded portions of North Texas to a Moderate Risk for what is anticipated to be a semi-focused sub-regional corridor of supercells
including very large hail potential along with some damaging
wind/tornado risk centered on mid-afternoon through
early/mid-evening.

First, a loosely organized complex of storms continues to progress east-northeastward along the Red River of southeast
Oklahoma/northeast Texas and broader parts of eastern Oklahoma at
late morning. Additional increasingly surface-based development
seems probable on this near-frontal zone and associated moist axis
and thermal gradient that extends east-northeastward to the Mid-South/ArkLaMiss. This may include supercells as well as the
possibility of an upscale-growing complex. Other initially elevated
severe storms are expected to continue and increase today from
northeast Oklahoma across the Ozarks toward parts of the
Mid-South/Mississippi Valley. Large hail is the initial risk, but a surface-based storm risk could develop pending boundary layer
warming.

Broadly speaking outside on ongoing storms, a strongly unstable
airmass exists across the southern Plains to the ArkLaTex, along and
near a slowly retreating/northward-returning warm front. This is
beneath relatively strong winds aloft, particularly in
mid/high-levels based on morning upper-air data. Additional intense surface-based convective development is forecast near the triple
point in north-central Texas towards the ArkLaTex this afternoon,
where extreme instability (4000+ J/kg MLCAPE) and very strong
deep-layer shear (50-60+ kt) will support the potential for multiple
intense supercells. Very large to giant hail (2-4+ inches) may occur
with the strongest supercells given the overall very favorable
environment and presence of steep mid-level lapse rates. Some
tornado threat may also exist with these supercells, even though
low-level shear is not forecast to be overly strong.

Additional severe storms are expected as far east as Mississippi and
Alabama today -- see Mesoscale Discussion 594 for short-term
details. An additional secondary round of upscale-growing storms
with increasing damaging wind potential could also move into this
same region late today, or more so tonight.

..Guyer/Chalmers.. 04/28/2026

$$

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ACUS01 KWNS 282002
SWODY1
SPC AC 282000

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0300 PM CDT Tue Apr 28 2026

Valid 282000Z - 291200Z

...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS ACROSS NORTH
TEXAS...

...SUMMARY...
Multiple rounds of severe thunderstorms will occur across parts of
the southern Plains into the lower Mississippi/Tennessee Valleys and
Southeast through this evening. Very large to giant hail (2-4+
inches), swaths of severe/damaging winds, and a few tornadoes are
all possible.

...20Z Update...
The previous forecast remains on track, and only minor adjustments
were made with this update. Most noteworthy, the CIG2 (intensity
level 2/2) hail area was expanded northward into south-central OK,
where robust splitting supercells are evolving in an environment
characterized by 2500-3000 J/kg MLCAPE and around 50 kt of effective
shear. These storms will continue to pose a risk of very large hail
through the afternoon. In north TX, a corridor of relatively higher
tornado potential is evident along a remnant outflow boundary --
where low-level shear is locally enhanced. Refer to Tornado Watch
171 and MCD 599 for more information.

..Weinman.. 04/28/2026

.PREV DISCUSSION... /ISSUED 1151 AM CDT Tue Apr 28 2026/

...Southern Plains to Lower Mississippi Valley/Southeast...
Have upgraded portions of North Texas to a Moderate Risk for what is anticipated to be a semi-focused sub-regional corridor of supercells
including very large hail potential along with some damaging
wind/tornado risk centered on mid-afternoon through
early/mid-evening.

First, a loosely organized complex of storms continues to progress east-northeastward along the Red River of southeast
Oklahoma/northeast Texas and broader parts of eastern Oklahoma at
late morning. Additional increasingly surface-based development
seems probable on this near-frontal zone and associated moist axis
and thermal gradient that extends east-northeastward to the Mid-South/ArkLaMiss. This may include supercells as well as the
possibility of an upscale-growing complex. Other initially elevated
severe storms are expected to continue and increase today from
northeast Oklahoma across the Ozarks toward parts of the
Mid-South/Mississippi Valley. Large hail is the initial risk, but a surface-based storm risk could develop pending boundary layer
warming.

Broadly speaking outside on ongoing storms, a strongly unstable
airmass exists across the southern Plains to the ArkLaTex, along and
near a slowly retreating/northward-returning warm front. This is
beneath relatively strong winds aloft, particularly in
mid/high-levels based on morning upper-air data. Additional intense surface-based convective development is forecast near the triple
point in north-central Texas towards the ArkLaTex this afternoon,
where extreme instability (4000+ J/kg MLCAPE) and very strong
deep-layer shear (50-60+ kt) will support the potential for multiple
intense supercells. Very large to giant hail (2-4+ inches) may occur
with the strongest supercells given the overall very favorable
environment and presence of steep mid-level lapse rates. Some
tornado threat may also exist with these supercells, even though
low-level shear is not forecast to be overly strong.

Additional severe storms are expected as far east as Mississippi and
Alabama today -- see Mesoscale Discussion 594 for short-term
details. An additional secondary round of upscale-growing storms
with increasing damaging wind potential could also move into this
same region late today, or more so tonight.

$$

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ACUS01 KWNS 290103
SWODY1
SPC AC 290101

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0801 PM CDT Tue Apr 28 2026

Valid 290100Z - 291200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF NORTHEAST TEXAS...ARKANSAS...NORTHERN LOUISIANA...AND
MISSISSIPPI...

...SUMMARY...
Severe thunderstorms will continue this evening across parts of the
ArkLaTex into the Lower Mississippi Valley. Very large hail (2+
inches), swaths of severe/damaging winds, and a few tornadoes are
all possible.

...01z Update...

Scattered severe thunderstorms are ongoing across northeast TX into
AR, MS and vicinity. A mix of storms modes, including supercells and
bowing segments will persist into the nighttime hours. Areas of
large to very large hail (2+ inches with strongest cells), a few
tornadoes (a couple could be strong), and damaging wind gusts remain
possible over the next several hours.

The main outlook changes were to reduce severe probabilities across
areas where storm potential has diminished, particularly for the
Lever 4 of 5 (Moderate) risk area in TX where storms have moved
southeast out of that area and redevelopment to the north appears
unlikely.

..Leitman.. 04/29/2026

$$

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ACUS01 KWNS 290455
SWODY1
SPC AC 290453

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1153 PM CDT Tue Apr 28 2026

Valid 291200Z - 301200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF TEXAS AND THE GULF COAST STATES INTO SOUTHERN GEORGIA AND SOUTH CAROLINAS...AND ACROSS THE CENTRAL APPALACHIANS/SOUTHERN
MID-ATLANTIC...

...SUMMARY...
Widely scattered strong to severe storms may impact a corridor from
south of the Texas Big Bend into the Gulf coast states and southern Georgia/South Carolina Wednesday afternoon into evening. Additional
strong storms are expected across the central Appalachians and
southern Mid-Atlantic.

...Synopsis...

An upper trough will pivot across the Great Lakes and Midwest today.
Within southern stream flow, a weak shortwave impulse will migrate
through westerly flow aloft from Texas to the GA/SC coast. This will
result in enhanced westerly flow across the southern U.S. and the
Midwest to the Mid-Atlantic. At the surface, a cold front is
forecast to extend from northern IN southwestward into central TX
this morning. This front will develop southward across TX and
southeastward across the Lower MS Valley and Southeast through the
period. The northern extent of the front will shift east across the
Midwest to the Mid-Atlantic. This surface boundary will be a focus
for strong to severe thunderstorm development during the
afternoon/evening.

...TX to GA/SC Coast...

A moist airmass will be in place ahead of the surface front,
particularly across TX where dewpoints in the 70s are common.
Heating into the 80s and 90 of this very moist airmass will result
in a corridor of moderate to strong MLCAPE. The surface boundary
will be the main forcing mechanism for convection across TX and
storm coverage may remain isolated. Further east into the Lower MS Valley/Southeast, a shortwave impulse will provide modest forcing
for ascent in addition to the southeast sagging cold front.

Isolated supercells across central TX will pose a risk for large
hail, with some potential for 2+ inch hail. Uncertainty concerning
storm coverage and capping across TX precludes an upgrade to Sight
risk at this time. Additional storms are expected to develop closer
to the Sabine Valley and Lower MS Valley this afternoon. Initial
thunderstorm clusters may congeal into one or more linear segment
and move across MS/AL/GA during the late afternoon into evening
hours. Hail and strong wind gusts will be possible with this
activity.

...Central Appalachians/Mid-Atlantic vicinity...

An upper shortwave trough emanating from the Great Lakes/Midwest
upper trough will overspread the region during the afternoon/evening
in tandem with the eastward advancing cold front. Modest boundary
layer moisture is forecast across the region, with dewpoints
generally in the 50s to near 60 F. Modest heating will result in
weak destabilization (generally 500-750 J/kg or less). Despite weak instability, supercell wind profiles are evident in forecast
soundings. This should aid in at least transient organization of
stronger updrafts with a wind and hail risk. While instability and
moisture will be marginal, 0-1 SRH will approach 150 m2/s2 in
proximity to a weak surface low and a brief tornado could also
occur.

..Leitman/Moore.. 04/29/2026

$$

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