ACUS03 KWNS 121932
SWODY3
SPC AC 121930

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0230 PM CDT Sun Apr 12 2026

Valid 141200Z - 151200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF
THE SOUTHERN PLAINS TO THE GREAT LAKES...

...SUMMARY...
Isolated to scattered severe thunderstorms are expected on Tuesday
and Tuesday night from the Southern Plains to the Great Lakes.

...Synopsis...
The western US trough will eject across the Rockies on Tuesday with strengthening westerly flow overspreading the Plains into the Great
Lakes Region. A surface low will deepen across western KS/NE with a
warm front lifting across the Lower Missouri Valley into the Great
Lakes and sharpening dryline across the southern/central Plains. A
cold front will sag southward across the Upper Midwest/Great Lakes
vicinity. The surface trough/dryline and the boundary across the
Great Lakes will become a focus for thunderstorm activity through
the forecast period.

...Lower MO Valley to the Great Lakes...
Convective coverage will overlap the start of the period near 12z on
Tuesday across portions of the Midwest/Great Lakes Region. Trends
are for relatively quick clearing across portions of central Iowa
into Illinois. As the warm front lifts northward, strong daytime
heating is expected amid dew points in the low to mid 60s. It is
likely the air mass will recover with potential for moderate to
strong instability by the afternoon. Stronger height falls are not
expected across the region, as the main upper trough
will be focused well to the southwest. However, warm advection atop
a southward-sagging surface boundary should support isolated to
scattered storm development by late afternoon/evening. The primary
risk will be for large to very large hail ( some 2.5"+ in diameter)
and damaging wind.

By late afternoon/evening, 700 mb flow will strengthen (around 50-60
kts) with a plume of steep low to mid-level lapse rate nosing into
central Iowa/northern Illinois from the southwest. The 850 mb
low-level jet also increases, with large clockwise curved hodographs
developing with the resulting increase in low-level shear. If
supercells can develop and maintain residency along or south of the
warm front, a corridor of greater tornado risk (a couple of which
may be strong tornadoes) may present itself.

Consideration was given to a 30 percent area (primarily hail
driven). With some uncertainty remaining in morning convection and
coverage of storms in the afternoon/evening, the 15% was maintained
with this outlook until more information can be gleaned from hi-res
guidance.

...Southern Plains...
Ahead of the dryline across the Southern Plains, strong daytime
heating is expected. Large-scale ascent will begin overspreading the
region by late afternoon/evening as the western upper trough finally
begins to eject eastward. As this occurs, mixing and convergence
along a surface dryline should support storm development by around
00z. If little convective development occurs on D2/Monday, a
relatively undisturbed moist/very unstable air mass will be in
place. It is likely that rather robust thunderstorm development will
occur along the dryline, with the primary mode being supercelluar.
Large to very large hail (2 to locally 2.5+ inches in diameter),
damaging wind, and a couple of tornadoes will be possible. Given
that deep layer shear profiles have more of a parallel component to
the dryline, storm interactions may keep the period of more discrete
supercell thunderstorms short, with a shift to clusters of mix-mode
supercell and multi-cell storms.

..Thornton.. 04/12/2026

$$

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ACUS03 KWNS 130717
SWODY3
SPC AC 130716

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0216 AM CDT Mon Apr 13 2026

Valid 151200Z - 161200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTION OF
THE SOUTHERN PLAINS INTO SOUTHERN WISCONSIN...

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

...Southern Plains to Great Lakes...

An upper trough will move from the Plains to the MS Valley vicinity
on Wednesday. As associated corridor of enhanced southwesterly
deep-layer flow will overspread a moist/unstable airmass ahead of a
surface dryline. The southern Plains portion of the dryline will not
move too much on Wednesday. However, the northern extent of this
boundary will intersect a weak surface low moving from the Lower MO
Valley toward Lake Michigan. This portion of the boundary will
advance eastward toward the MS River during the evening/overnight
hours.

Areas of showers and thunderstorms may be ongoing across portions of
the region Wednesday morning. As a result, there is uncertainty
regarding how the boundary layer may recover/destabilize during the
afternoon. Nevertheless, at least pockets of moderate
destabilization (1000-2000 J/kg MLCAPE) are expected within a
corridor along and east of the surface boundary. Effective shear
magnitudes greater than 40 kt will be sufficient for organized
convection, with large hail and strong wind gusts being the primary
hazards.

..Leitman.. 04/13/2026

$$

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ACUS03 KWNS 131922
SWODY3
SPC AC 131921

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0221 PM CDT Mon Apr 13 2026

Valid 151200Z - 161200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTION OF THE
SOUTHERN PLAINS INTO SOUTHERN WISCONSIN...

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

...Synopsis...
The upper-level trough will move eastward from the Plains into the
Upper Midwest on Wednesday, with continued enhanced west to
southwesterly flow across the southern Plains into the Great Lakes
Region. The surface dryline will remain in a similar location from
Tuesday, extending across western Oklahoma into southwestern and
western Texas. A surface low will shift eastward across IA into WI,
with a cold front shifting south and east through the period.
Scattered thunderstorm development is expected from the Southern
Plains into the Upper Midwest along the aforementioned boundaries
Wednesday afternoon and evening.

...Southern Plains to Great Lakes...
Widely scattered showers and thunderstorms will be ongoing at the
start of the period at 12z Wednesday across much of the Slight Risk
region. A secondary round of thunderstorm development is likely to
occur near and ahead of the dryline extending from west Texas into
western Oklahoma Wednesday afternoon. It remains somewhat uncertain
how morning convection will evolve and what the resulting effect on
the thermodynamic environment will be. Most guidance suggests that
in the area ahead of the dryline across central OK to the Red River
in northern Texas will develop at least moderate instability
(1000-2000 J/kg of MLCAPE). Deep layer shear profiles will remain
strong favoring supercells as the primary mode. The main threat will
be for large to very large hail and damaging wind, given linearly
elongated hodographs and weaker low-level shear.

Thunderstorms are also expected to re-develop further north across
the central Plains into the Great Lakes region along the
dryline/cold front intersection. A messy mode with mix of supercells
and multi-cell clusters is likely given the eventual southward
moving cold front. Similarly, the main risks will be for damaging
wind and large hail across these regions.

...Northeast...
Shower and thunderstorm activity is expected to develop along and
south of a diffuse frontal boundary across the Great Lakes into
southern NY/northern PA. Modestly unstable profiles, steepening
lapse rates, and strong deep layer shear will allow for some
isolated severe storm risk. Primary risk would be for damaging wind
and small hail, though, a tornado could be possible near the
boundary.

..Thornton.. 04/13/2026

$$

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ACUS03 KWNS 140723
SWODY3
SPC AC 140722

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0222 AM CDT Tue Apr 14 2026

Valid 161200Z - 171200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE OHIO
VALLEY...

...SUMMARY...
Isolated strong to severe thunderstorms are possible on Thursday
across portions of the Ohio Valley.

...Lower Ohio Valley/Midwest vicinity...

An upper shortwave trough will move from the MS Valley to the
Appalachians on Thursday. Moderate southwesterly deep-layer flow
will overspread the MO Bootheel toward Lake Erie ahead of this
feature. At the surface, a corridor of upper 50s to low 60s F
dewpoints will be in place ahead of a surface front. Some ongoing
convection and cloudiness early in the day will limit stronger
destabilization, but at least weak MLCAPE around 500-1000 J/kg is
forecast. While low-level flow will be weak, around 30-40 kt
west/southwesterly flow between 850-700 mb and 40+ kt effective
shear magnitudes will aid in some storm organization. A mix of
clusters and line segments will bring a risk of locally strong gusts
where stronger heating results in steepened low-level lapse rates.

...Southern Plains vicinity...

A conditionally favorable supercell environment will be in place
across the southern Plains on Thursday ahead of a dryline. A weak
shortwave impulse is forecast to move across the region early in the
day, departing by early afternoon. Height rises/shortwave ridging is
then forecast to build across the area. At this time, thunderstorm
development is not forecast as weak capping in the absence of
large-scale ascent should be maintained. However, trends will be
monitored given the otherwise very favorable thermodynamic and
kinematic environment. Otherwise, isolated elevated convection is
possible late in the period in a warm advection regime across north
TX into southern OK.

..Leitman.. 04/14/2026

$$

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ACUS03 KWNS 141916
SWODY3
SPC AC 141915

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0215 PM CDT Tue Apr 14 2026

Valid 161200Z - 171200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE LOWER
OHIO VALLEY REGION INTO PARTS OF NEW YORK...

...SUMMARY...
Isolated strong to severe thunderstorms are possible on Thursday
extending from southeast Missouri across the Ohio Valley and into
parts of New York.

...Synopsis...
A progressive pattern will persist on Thursday, with a leading
shortwave trough moving quickly across OH valley into the Northeast.
This wave will breakdown the ridge along the East Coast, and provide
a focus for scattered strong storms. Low-level warm advection out of
the west/southwest will help destabilize the region with storms most
likely during the afternoon from the Lower Great Lake across much of
upstate NY and northern PA. Instability will be sufficient to
support a few fast-moving cells capable of marginal hail and locally
damaging gusts.

To the southeast, storm coverage is less certain, particularly from
AR/MO into the lower OH Valley. Here, cool temperatures aloft will
linger, aiding instability, though somewhat behind the upper trough
affecting the northeastern states. Showers and storms are most
likely in the morning in association with the main wave, but
conditional severe probabilities will be higher during the afternoon
when instability redevelops. Any storms that form will be capable of
producing hail, from MO into AR, western TN/KY, IL and IN.

..Jewell.. 04/14/2026

$$

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ACUS03 KWNS 150729
SWODY3
SPC AC 150728

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0228 AM CDT Wed Apr 15 2026

Valid 171200Z - 181200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF NORTHERN OKLAHOMA AND EASTERN KANSAS...MISSOURI...IOWA...AND FAR
NORTHWEST ILLINOIS...

...SUMMARY...
Widespread severe thunderstorms are expected from parts of the
southern Plains to the Middle and Upper Mississippi Valley vicinity
on Friday and Friday night. All severe hazards will be possible.

...Southern Plains to MS Valley...

A robust upper trough will eject eastward from the northern High
Plains and central Rockies to the Upper Midwest and central Plains
on Friday. As this occurs, strong deep-layer southwesterly flow will
overspread portions of the central/southern Plains to the Mid/Upper
MS Valley and Great Lakes. Flow at 850-700 mb around 40-60 kt will
be common. At the surface, a cold front will extend from northern MN
to a low over eastern NE Friday morning. Meanwhile, a dryline will
extend southwest from the NE low into central KS, northwest OK and
western TX. A warm front initially arcing across central IA into
south-central IL will lift northward through the period ahead of the eastward-advancing surface low tracking across northern IA/southern
MN into WI. A warm sector characterized by mid/upper 60s F dewpoints
will be in place across the southern Plains to the Mid-MS Valley by
midday, with a narrow plume of low 60s F dewpoints extending north
into portions of eastern MN and WI. Steep midlevel lapse rates (7-8
C/km) will overspread this moist boundary layer, resulting in
moderate to strong destabilization.

As strong ascent overspreads the aforementioned surface boundaries
by mid afternoon, widespread thunderstorm development is expected.
While initial supercells are possible given a favorable
thermodynamic environment and supercell vertical wind profiles,
linear forcing along the front combined with strong deep-layer
southwesterly flow parallel to the initiating boundary may result in
rapid upscale development into a QLCS, particularly from northeast
KS/northwest MO into IA. A well-organized line of convection will
pose a damaging wind risk along with possible QLCS tornadoes as
convection develops eastward through the afternoon/evening. If any
discrete supercells develop, an all-hazards risk will also accompany
that activity.

Further south across southern KS into OK, supercell development may
be more probable, at least initially. Convection will initially
develop along the dryline prior to the cold front overtaking this
boundary later in the evening. Any supercells that develop and can
maintain discrete characteristics will pose a risk for very large
hail, strong tornadoes, and damaging winds. With time, the cold
front will overtake the dryline during the evening and move
southeast overnight. Linear convection is expected along the front,
posing a damaging wind and isolated tornado risk during the
nighttime hours.

Capping, weakening large-scale ascent and more modest vertical shear
with southern extent may limit storm potential along the dryline in western/west-central TX.

..Leitman.. 04/15/2026

$$

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ACUS03 KWNS 151933
SWODY3
SPC AC 151932

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0232 PM CDT Wed Apr 15 2026

Valid 171200Z - 181200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM OKLAHOMA NORTHEASTWARD INTO IOWA AND ILLINOIS...

...SUMMARY...
Widespread severe thunderstorms are expected from parts of the
southern Plains to the Middle and Upper Mississippi Valley vicinity
Friday into Friday night. A few tornadoes, possibly strong, very
large hail, and damaging winds will be possible.

...Synopsis...
An upper trough will move out of the Rockies and into the Plains on
Friday, with primary midlevel speed max intensifying from the
central Plains into the upper MS Valley. A southern stream system
will also intensify the upper-wind pattern from northern Mexico into
the southern Plains.

At the surface, a cold front is forecast to extend from MN into KS
Friday morning, progressing roughly to a WI to central MO to
northern OK line by 00Z. Meanwhile, a warm front will push north
into WI, extending southeastward near Chicago.

Of particular note for this setup are model trends, which have
consistently shown the cold front pushing farther east and south
than the previous model runs. This results in a lower confidence
forecast in terms of the precise area of greatest threat and degree
of tornado potential.

Despite these uncertainties, the environment ahead of the cold front
will be quite favorable for supercells, with steep midlevel lapse
rates, ample shear, and strong instability. These factors will
clearly favor very large damaging hail, a risk of tornadoes, and
eventually damaging winds. A broad 40-50 kt low-level jet will
contribute to favorable low-level shear for tornadoes, and a couple
strong tornadoes will be possible prior to the cold front and
aggregate outflows undercutting the initial activity. Favored areas
for tornadoes will be southern KS into western/northern OK in
proximity to the dryline, and farther north into eastern IA and
southern WI where SRH will be stronger near the low.

Even if the cold front surges faster than currently indicated, a
widespread damaging wind threat could occur. Trends will continue to
be monitored as the event nears.

..Jewell.. 04/15/2026

$$

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ACUS03 KWNS 160707
SWODY3
SPC AC 160705

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0205 AM CDT Thu Apr 16 2026

Valid 181200Z - 191200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
THE OHIO VALLEY...

...SUMMARY...
Isolated strong to severe thunderstorms capable of damaging winds
and hail will be possible on Saturday across part of the Ohio
Valley.

...Ohio Valley...

A large-scale upper trough oriented over the Upper Midwest and
Plains will shift east over the Great Lakes, Midwest and TN Valley
on Saturday/Saturday night. Strong deep-layer southwesterly flow
will overspread the Ohio Valley ahead of an eastward-advancing cold
front. This front should be located from Lower MI into southeast MO
Saturday morning, moving across the Ohio Valley through early
evening. Modest boundary-layer moisture will be in place ahead of
the front. Daytime heating into the 70s and modestly steep midlevel
lapse rates will support weak destabilization (generally less than
1000 J/kg MLCAPE). While instability will be modest, strong low and
midlevel flow will support organized cells and/or line segments
capable of strong gusts. Any discrete cellular activity also may
produce marginally severe hail. These severe risk should gradually
wane during the evening with eastward extent.

...TX to the Lower MS Valley...

Thunderstorms are expected along a southeast-advancing cold front
Saturday afternoon and evening. Deep-layer flow will be oriented
parallel to the front, and convection may largely be anafrontal or
quickly undercut by the front. While weak MUCAPE is noted in
forecast soundings, severe potential is not expected at this time.

..Leitman.. 04/16/2026

$$

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ACUS03 KWNS 161927
SWODY3
SPC AC 161926

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0226 PM CDT Thu Apr 16 2026

Valid 181200Z - 191200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER MUCH OF THE
UPPER OHIO VALLEY...

...SUMMARY...
Scattered strong to severe thunderstorms capable of damaging winds
and hail will be possible on Saturday from the upper Ohio Valley.

...Synopsis...
An upper trough will move toward the upper Great Lakes and OH Valley
on Saturday, with a cold front moving quickly east and extending
from western NY/PA into KY/TN by 00Z. A narrow plume of upper 50s F
to near 60 F dewpoints will exist and contribute to up to 1000 J/kg
MUCAPE.

Storms will likely be ongoing early in the day along the front as it
moves out of IN and into western OH/KY, and 40-50 kt southwest winds
at 850 mb may support damaging gusts potential. Heating ahead of the
front from OH/PA southward into WV/KY/TN may support new
development, although lapse rates aloft over southern areas will be
poor. Still, favorable deep-layer mean wind speeds and sufficient
shear may support isolated severe gusts or marginal hail, especially
into OH/western PA. Further, low-level shear will be strongest over
northern areas, with some supercell potential.

..Jewell.. 04/16/2026

$$

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ACUS03 KWNS 170655
SWODY3
SPC AC 170653

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0153 AM CDT Fri Apr 17 2026

Valid 191200Z - 201200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe thunderstorms are not expected on Sunday.

...Synopsis...
A strong mid-level trough will move from the Great Lakes to
southeast Canada during the day on Sunday. A cold front is forecast
to initially exist from southeast Virginia to the Florida Panhandle.
The cold front will move into the Atlantic and Gulf as surface high
pressure builds in its wake.

Some lingering moisture and weak instability will likely be present
ahead of the front Sunday morning. By late morning, heating may be
sufficient for some storms along and ahead of the front. However,
given the weak instability, no severe weather is expected. This
front will continue southeast into the Atlantic/Gulf by late
afternoon and bring an end to any storm threat across the CONUS
(except for the Florida Peninsula).

..Bentley.. 04/17/2026

$$

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ACUS03 KWNS 171926
SWODY3
SPC AC 171925

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0225 PM CDT Fri Apr 17 2026

Valid 191200Z - 201200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe thunderstorms are not expected on Sunday.

...Discussion...
An amplified large-scale trough will move eastward from the Great
Lakes to the Northeast on Sunday, while a related cold front moves
off the Eastern Seaboard. Despite poor deep-layer lapse rates, a
narrow corridor of diurnal heating amid lower/middle 60s dewpoints
(higher over the FL Peninsula) ahead of the front should support
isolated thunderstorms from the coastal Carolinas southward across
parts of the FL Peninsula. Weak/narrow buoyancy profiles will limit thunderstorm intensity and the severe risk.

..Weinman.. 04/17/2026

$$

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ACUS03 KWNS 180709
SWODY3
SPC AC 180708

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0208 AM CDT Sat Apr 18 2026

Valid 201200Z - 211200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe storms are not expected on Monday.

...Discussion...
High pressure and a dry airmass will limit thunderstorm potential
across most of the CONUS on Monday. The only exceptions will be
across South Florida and parts of the Southwest into West Texas.
Across South Florida, mid 60s dewpoints are forecast to persist on
Monday which may allow for sufficient instability for scattered
storm development. Weak instability should limit any severe weather
threat with this activity.

Additional isolated storms are possible across parts of the
Southwest into portions of West Texas as moisture return may lead to
some weak instability. No severe storms are expected from this
activity.

..Bentley.. 04/18/2026

$$

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ACUS03 KWNS 181916
SWODY3
SPC AC 181915

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0215 PM CDT Sat Apr 18 2026

Valid 201200Z - 211200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Severe storms are not expected on Monday.

...Discussion...
A midlevel trough will move from the Northeast off the New England
coast on Monday, while the tail end of a related cold front
continues southward into the Caribbean Sea. North of the front in
southern FL, diurnal heating amid a moist post-frontal air mass
should support isolated to widely scattered thunderstorms, though
weak buoyancy and limited large-scale forcing for ascent should
limit the severe risk.

Farther west, weak low-level warm advection and modest moisture
return ahead of a low-amplitude midlevel impulse moving into south
TX will support a couple rounds of isolated/elevated thunderstorms
across southwest TX. Isolated thunderstorm potential could spread
further north into central TX late in the period, though confidence
in this scenario is currently low. Additional diurnal thunderstorms
are possible across the Southwest as the midlevel moisture impinges
on the region, with most of this activity expected over the higher
terrain.

..Weinman.. 04/18/2026

$$

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ACUS03 KWNS 190728
SWODY3
SPC AC 190727

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0227 AM CDT Sun Apr 19 2026

Valid 211200Z - 221200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Thunderstorms will be possible across the western CONUS, the
south-central CONUS, and the southern Great Lakes. No severe weather
is anticipated.

... Synopsis ...

A large-scale midlevel trough will move push inland across the
western CONUS into the Great Basin on Wednesday, with downstream
ridging building across the central CONUS in response. Across the
Northeast, northwest flow aloft will prevail downstream of the
central CONUS ridge. An embedded jet streak and associated vorticity
maximum within the northwest flow will aid driving a weak surface
low and attendant frontal boundary southeast across the Great Lakes
through the forecast period. Meanwhile, the surface ridge across the
Southeast will move east, just offshore of the Southeast Atlantic
Coast, promoting return flow across the Plains. The return flow will
be aided by the development of lee troughing across much of the High
Plains.

... Western US ...

Scattered showers are expected across portions of the West in
association with the inland-moving large-scale trough. Seasonably
cool midlevel temperatures will support enough instability for a few thunderstorms, although severe potential is very low.

... South-central US ...

Showers and thunderstorms will be possible across the region within
the return flow regime. Here, weak warm-air advection combined with
between 500-1000 J/kg of MUCAPE will support convective development.
Weak vertical shear and the lack of strong forcing for ascent should
limit any severe potential.

... Southern Great Lakes ...

Scattered showers a few thunderstorms will be possible within the
surface frontal zone as it pushes south/southeast during the day.
Instability around 500 J/kg MUCAPE and weak effective layer shear
should preclude a more robust severe weather event, but a strong
wind gust or two may be possible.

..Marsh.. 04/19/2026

$$

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ACUS03 KWNS 191937
SWODY3
SPC AC 191936

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0236 PM CDT Sun Apr 19 2026

Valid 211200Z - 221200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Thunderstorms will be possible across the western CONUS, the
south-central CONUS, and the southern Great Lakes on Tuesday.
Potential for severe weather appears low.

...Synopsis...
Upper ridging will be the primary feature across much of the CONUS
from the eastern Great Basin into Plains on Tuesday. Moderate
northwesterly flow aloft will remain across the Upper Midwest and
portions of the Ohio Valley in the wake of a stronger upper trough.
Along the West Coast, an upper trough is expected to slowly move
ashore in central California into the western Great Basin. At the
surface, continued presence of high pressure in the Southeast and
off the Atlantic coast will drive moisture return into a
stalled/remnant cold front in central Plains and Lower Great Lakes
vicinity.

...Lower Great Lakes...
Modest moisture return ahead of the boundary is expected to promote
isolated to widely scattered thunderstorms. This may not occur until
early/mid evening, however. Temperatures will be quite cold aloft
(perhaps near -20 C at 500 mb), but moisture could be quite limited (potentially in the 40s F). The NAM is again the most aggressive
with moisture return as compared to other guidance. Should
sufficient moisture return occur, shear will be sufficient for
marginally organized convection capable of strong gusts and hail.
Uncertainty is high given how dry the airmass is preceding this
moisture return and convection near the Gulf Coast on preceding days
will potentially slow northward progress.

...Central Valley California...
Ahead of the upper low, southeasterly winds may develop within the
Valley. While destabilization will not be overly strong, pockets of
heating could lead to modest MLCAPE values by the afternoon. Shear
will be a limiting factor for overall severe potential, but a
stronger storm or two is possible.

...Central Texas...
Convection will be ongoing early Tuesday morning. Modest deep-layer
shear and elevated buoyancy could promote a couple stronger storms
capable of small hail. However, storms should generally become less
organized with time as upper-level ridging builds in through the
day.

..Wendt.. 04/19/2026

$$

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ACUS03 KWNS 200728
SWODY3
SPC AC 200727

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0227 AM CDT Mon Apr 20 2026

Valid 221200Z - 231200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE HIGH PLAINS OF NEBRASKA SOUTH INTO THE TEXAS PANHANDLE...

...SUMMARY...
Severe thunderstorms capable of hail and gusty winds may develop
during the late afternoon and evening across portions of the High
Plains. Elsewhere, thunderstorms will be possible across the
northern Gulf Coast and portions of the Ohio Valley.

... Synopsis ...

A shortwave trough will eject northeast out of the basal region of
the western CONUS trough and into the northern Plains on Wednesday.
As this happens, strengthening southerly/southwesterly midlevel flow
will overspread much of the High Plains. A surface cyclone over
eastern Montana will gradually deepen as it slowly moves east.

... Central High Plains south into the southern High Plains ...

As the Montana surface cyclone gradually deepens on Wednesday, Gulf
moisture will be drawn northward into the central and northern
Plains. As the upper trough approaches the region during the late afternoon/evening, modest height falls are expected to overspread a
sharpening dryline across far eastern Colorado or western Nebraska
south into the Texas Panhandle. Kinematic profiles up and down the
dryline show ample vertical shear for supercells capable of
producing hail and gusty winds. However, considerable uncertainty
remains regarding thunderstorm coverage owing to the significant
differences in the depth and quality of the boundary layer moisture
return noted in the 20260420/00Z guidance suite. For example, the
NAM is nearly 5F more moist along the dryline across portions of
Nebraska than global models.

That said, pattern recognition and 00Z RRFS suggest that at least a
couple of storms should develop along the dryline from Nebraska
south into the eastern Texas Panhandle. Deep-layer flow will largely
parallel the dryline during the afternoon which should preclude much
eastward advancement. A 5% unconditional risk area has been added to
account for this potential.

... Elsewhere Across the CONUS ...

Thunderstorms may be ongoing at the start of the forecast period and
persist into the early afternoon across portions of the northern
Gulf Coast. The thunderstorm potential should wane with time as
increasing midlevel heights suppress large-scale ascent.

Additionally, modest low-level moisture and weak instability may
support a few lightning strikes within a weak surface boundary
across the Ohio Valley.

..Marsh.. 04/20/2026

$$

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ACUS03 KWNS 201931
SWODY3
SPC AC 201930

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0230 PM CDT Mon Apr 20 2026

Valid 221200Z - 231200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE
HIGH PLAINS...

...SUMMARY...
Severe thunderstorms capable of hail and gusty winds may develop
during the late afternoon and evening across portions of the High
Plains.

...Synopsis...
A broad trough will begin to move into the Rockies and adjacent High
Plains. A shortwave trough will eject into the northern Plains in
association with the broader trough. At the surface, a deep surface
low will develop in eastern Montana with a lee trough/dryline
extending into the southern High Plains.

...High Plains...
As the upper-trough approaches the Rockies, the lee trough and
dryline are expected to sharpen. Forcing for ascent will be
strongest in the Nebraska Panhandle/western South Dakota vicinity.
This area is also has the largest variability in terms of moisture
return (the NAM being much more bullish than the ECMWF). Farther
south, moisture will generally be greater. Guidance is in agreement
that 60s F dewpoints are probable in the Texas South Plains and
perhaps parts of the Panhandle. The issue farther south will be the
lack of synoptic ascent. Temperatures behind the dryline will be in
the upper 80s F to perhaps low 90s F. The depth of the circulation
may be enough to initiate an isolated storm or two, but confidence
is still not overly high. Environmentally, deep-layer shear will be
oriented roughly perpendicular to the dryline, especially from
western Kansas southward. Supercells would be favored if storms
develop. MLCAPE of 1000 J/kg in South Dakota to 1500-2500 J/kg
farther south is expected by the afternoon. Large hail and severe
wind gusts would be possible.

...Central/Easter Montana...
With the surface low deepening through the day, at least modest
moisture return northwestward is anticipated into central/eastern
Montana. However, moisture will still be quite scant across the
region. Dewpoints may not reach the 40s F. Given the forcing for
ascent, high-based convection is possible. The very dry sub-cloud
layers could lead to gusty outflow winds. At present, confidence in
severe gusts is too low to warrant wind probabilities.

..Wendt.. 04/20/2026

$$

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ACUS03 KWNS 210739
SWODY3
SPC AC 210738

Day 3 Convective Outlook CORR 1
NWS Storm Prediction Center Norman OK
0238 AM CDT Tue Apr 21 2026

Valid 231200Z - 241200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
SOUTHERN MINNESOTA SOUTHWARD INTO NORTHERN OKLAHOMA...

CORRECTED FOR TEXTUAL CLARITY

...SUMMARY...
Severe thunderstorms will be possible from northern Oklahoma into
southern Minnesota on Thursday. Large hail to very large hail,
damaging winds, and a few tornadoes are possible.

... Synopsis ...

A complex convective setup is expected on Thursday as a broad,
long-wave trough remains anchored across the Western US. While the initial/primary shortwave will be lifting northward into Canada, a
secondary, lower amplitude wave is progged to approach the Southern
Plains overnight Thursday into Friday.

At the surface, a Pacific cold front and dryline will push eastward
into the Central Plains. A secondary surface low is forecast to
develop near the triple point in northwest Oklahoma/southwest
Kansas. This feature will serve as the southern extent of the more
organized severe threat, with a conditional threat southward along
the dryline.

... Central Plains ...

Thunderstorms are expected to develop along an advancing cold
front/dryline across portions eastern Nebraska into western Iowa,
before expanding both north and south. MUCAPE values between
1500-2500 J/kg and deep-layer shear on the order of 30-40 knots will
support supercellular structures initially, but unidirectional
profiles may favor splitting supercells, storm interference, and a
tendency for upscale growth into one or more linear segments. While
a few tornadoes may be possible early in the convective evolution,
large hail and damaging winds should become the dominant threat with
time.

... Southern Plains ...

Convective initiation along the dryline south of the triple point
remains uncertain due to stronger capping. However, any discrete
cells that manage to initiate will do so in an environment
characterized by MUCAPE values between 2000-3000 J/kg with 30-40
knots of vertical shear. This will be more than sufficient to
support supercells capable of very large hail.

A secondary wave should approach the region overnight Thursday into
Friday morning. Forecast soundings indicate a steepening of midlevel
lapse rates associated with this feature and a subsequent increase
in CAPE values. Depending on the evolution of thunderstorms during
the afternoon and evening, additional thunderstorms may develop
overnight. The severe potential of these storms is uncertain given
the overnight timing of the wave and increasing convective
inhibition. However, strong vertical shear would seem to support a
hail and wind threat.

... Northern Plains/Upper Mississippi Valley ...

As the cold front pushes into the more modest moisture and buoyancy
profiles across northern Minnesota, the severe threat should be
lesser than areas to the south. Still, proximity to the upper wave
should support at least some threat for wind with any thunderstorms
that develop.

..Marsh.. 04/21/2026

$$

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ACUS03 KWNS 210731
SWODY3
SPC AC 210730

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0230 AM CDT Tue Apr 21 2026

Valid 231200Z - 241200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
SOUTHERN MINNESOTA SOUTHWARD INTO NORTHERN OKLAHOMA...

...SUMMARY...
Severe thunderstorms will be possible from northern Oklahoma into
southern Minnesota on Thursday. Large hail to very large hail,
damaging winds, and a few tornadoes are possible.

... Synopsis ...

A complex convective setup is expected on Thursday as a broad,
long-wave trough remains anchored across the Western US. While the initial/primary shortwave will be lifting northward into Canada, a
secondary, lower amplitude wave is progged to approach the Southern
Plains overnight Thursday into Friday.

At the surface, a Pacific cold front and dryline will push eastward
into the Central Plains. A secondary surface low is forecast to
develop near the triple point in northwest Oklahoma/southwest
Kansas. This feature will serve as the southern extent of the more
organized severe threat, with a conditional threat southward along
the dryline.

... Central Plains ...

Thunderstorms are expected to develop an advancing cold
front/dryline across portions eastern Nebraska into western Iowa,
before expanding both north and south from here. MUCAPE values
between 1500-2500 J/kg and deep-layer shear on the order of 30-40
knots will support supercellular structures initially. However,
unidirectional profiles will support splitting supercells and favor
an upscale growth into one or more linear segments. While a few
tornadoes may be possible early in the convective evolution, large
hail and damaging winds may become the dominant threat with time.

... Southern Plains ...

Convective initiation along the dryline south of the triple point
remains uncertain due to stronger capping. However, any discrete
cells that manage to initiate will do so in an environment
characterized by MUCAPE values between 2000-3000 J/kg with 30-40
knots of vertical shear. This will be more than sufficient to
support supercells capable of very large hail.

A secondary wave should approach the region overnight Thursday into
Friday morning. Forecast soundings indicate a steepening of midlevel
lapse rates associated with this feature and a subsequent increase
in CAPE values. Depending on the evolution of thunderstorms during
the afternoon and evening, additional thunderstorms may develop
overnight. The severe potential of these storms is uncertain given
the overnight timing of the wave and increasing convective
inhibition. However, strong vertical shear would seem to support an
ongoing hail and wind threat.

... Northern Plains/Upper Mississippi Valley ...

As the cold front pushes into the more modest moisture and buoyancy
profiles across northern Minnesota, the severe threat should be
lesser than areas to the south. Still, proximity to the upper wave
should support at least some threat for wind with any thunderstorms
that develop.

..Marsh.. 04/21/2026

$$

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ACUS03 KWNS 211938
SWODY3
SPC AC 211937

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0237 PM CDT Tue Apr 21 2026

Valid 231200Z - 241200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE
MID-MISSOURI VALLEY VICINITY INTO SOUTHERN KANSAS AND NORTHERN
OKLAHOMA...

...SUMMARY...
Severe thunderstorms will be possible from northern Oklahoma into
southern Minnesota on Thursday. Large hail to very large hail,
damaging winds, and a few tornadoes are possible.

...Synopsis...
Two shortwave troughs within a larger-scale trough over much of the
Rockies will pivot northeast on Thursday. The initial shortwave will
impact parts of the central Plains and mid-Missouri Valley. A
second, compact shortwave will pivot into parts of Oklahoma and
Kansas. At the surface, moisture return will continue ahead of a
Pacific cold front in the central Plains. A weak surface low is
expected to develop along the Oklahoma/Kansas border and track
eastward. Attendant to this low, a dryline will drape southward into
the Permian Basin.

...Central and southern Kansas...Oklahoma...
With mid-level ascent arriving mid/late afternoon, storms are likely
to initiate along the cold front as well as near the triple point
associated with the weak surface low along the KS/OK border.
Supercells are most likely near the triple point and could persist
so long as storm interactions remain minimal. 40-45 kts of shear and
2000-3000 J/kg MLCAPE will promote storms capable of all hazards,
including tornadoes and very-large hail. A strong low-level jet will
develop ahead of this activity during the evening. The tornado
threat could increase for storms that can remain discrete.

In Oklahoma, if and how many storms develop remains uncertain along
the dryline. Northern portions of Oklahoma are more likely to have
severe storms given the proximity to the surface low. A similar
environment will exist east of the dryline as does farther north
into southern Kansas. There is a conditional threat for all severe
hazards.

...Mid-Missouri Valley...
Storms are expected to develop along the cold front potentially as
early as mid afternoon. However, capping appears strong enough in
forecast soundings that initiation could delay until late afternoon.
Steep mid-level lapse rates will be in place along and ahead of the
front. Deep-layer shear will be 30-40 kts, but generally parallel to
the front. Initial storms could be supercellular and produce large
to very-large hail early in the convective cycle. Upscale growth
appears likely to occur rather quickly. Damaging/severe winds would
become the primary risk at that point. Tornadoes are also possible
given the low-level shear, both with initial supercells and perhaps
with QLCS circulations.

..Wendt.. 04/21/2026

$$

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ACUS03 KWNS 220722
SWODY3
SPC AC 220721

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0221 AM CDT Wed Apr 22 2026

Valid 241200Z - 251200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
THE SOUTHERN PLAINS INTO THE LOWER MISSISSIPPI VALLEY...

...SUMMARY...
A few severe thunderstorms will be possible across portions of the
Southern Plains into the Lower Mississippi Valley on Saturday. Large
hail and damaging wind gusts should be the primary threats.

... Synopsis ...

A persistent longwave trough will remain situated across the
northern US on Friday, maintaining a broad regime of cyclonic
midlevel flow over the western two-thirds of the country. Within
this broad flow, neutral to modest midlevel height rises are likely
across the Southern Plains. This evolution suggests a lack of robust large-scale forcing for ascent, with subtle subsidence potentially
acting as a limiting factor for widespread convective coverage.

... Southern Plains into the Lower Mississippi Valley ...


At the start of the forecast period, convective activity may be
ongoing across portions of northeast Oklahoma, southeast Kansas,
southern Missouri, or northern Arkansas along a consolidated outflow boundary/cold front. These storms should slowly weaken during the
morning with the loss of large-scale ascent and a weakening
low-level jet. The outflow boundary/cold front should slowly sag
south through the morning before stalling somewhere in the vicinity
of the I40 corridor. This feature will serve as the primary focus
for subsequent development later in the afternoon, with residual
outflow or differential heating boundaries being a secondary source
of initiation.

South of the frontal boundary, a highly unstable airmass will remain
in place across the warm sector. Strong diabatic heating of a moist
boundary layer will yield pockets of moderate-to-strong instability,
with MUCAPE values potentially in the 2000-3000 J/kg range. While
deep-layer shear is forecast to remain relatively modest (30-35
knots), the degree of instability will be sufficient to support
robust updrafts.

Given the modest shear and lack of stronger synoptic support, storm
modes will likely be multicell clusters or transient supercells. Any
persistent cell will be capable of producing large hail and
localized damaging wind gusts

... Lower Mississippi Valley ...

Convection that develops across Oklahoma and Arkansas during the
afternoon is expected to persist into the evening as it moves slowly east-southeast toward Mississippi and Tennessee. Although
instability is not as great with eastward extent, it should remain
sufficient enough to support some potential for sporadic wind and
hail through the overnight hours.

..Marsh.. 04/22/2026

$$

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ACUS03 KWNS 221931
SWODY3
SPC AC 221930

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0230 PM CDT Wed Apr 22 2026

Valid 241200Z - 251200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE
SOUTHERN PLAINS INTO THE LOWER MISSISSIPPI VALLEY...

...SUMMARY...
A few severe thunderstorms will be possible across portions of the
Southern Plains into the Lower Mississippi Valley on Friday. Large
hail and damaging wind gusts should be the primary threats.

...Southern Plains into the Lower MS Valley...
Storms may be ongoing at the start of the period Friday morning from
parts of OK into AR/MO, and possibly into the lower OH Valley. While
a general weakening trend is expected during the morning, the
strongest early-day storms could pose a threat of isolated hail and
localized strong/damaging gusts.

The primary severe threat is expected to develop from the afternoon
into the evening, along the primary outflow/cold front and any other
residual boundaries left over from the morning convection. The
strongest heating/destabilization is expected from parts of TX into
southeast OK, where MLCAPE of 2000-3000 may develop, with moderate
instability expected as far east as the lower MS/OH Valleys.

At this time, the greatest diurnal storm coverage is expected from
eastern OK/northeast TX into AR, where a weak midlevel shortwave
trough and potential MCV may overlap moderate to strong buoyancy.
Effective shear will be relatively modest (generally 30-35 kt), but
sufficient to support some storm organization. Initial diurnal
development in this region could pose a threat for hail and locally
damaging wind. Low-level flow/shear will generally remain weak, but storm/boundary interactions could also support a low tornado threat.
With time, consolidating outflows could support modest upscale
growth and a potential increase in damaging-wind potential into the
early evening as storms spread east-southeastward.

Storm coverage may remain quite isolated across western portions of
the Level 2/Slight Risk area, due to weak large-scale ascent, but
isolated development will be possible as CINH weakens. The strongly
unstable and sufficiently sheared environment will conditionally
favor a severe threat across parts of southern OK and north TX, if
storms can be sustained.

..Dean.. 04/22/2026

$$

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ACUS03 KWNS 230728
SWODY3
SPC AC 230727

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0227 AM CDT Thu Apr 23 2026

Valid 251200Z - 261200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF SOUTH-CENTRAL KANSAS INTO CENTRAL AND EASTERN OKLAHOMA AND FAR
NORTHWEST ARKANSAS...

...SUMMARY...
Severe thunderstorms will likely develop across portions of Oklahoma
and Kansas during the evening. These storms will pose a risk of very
large hail, damaging winds, and a couple of tornadoes. Isolated
severe thunderstorms may also develop across portions of North Texas
during the afternoon.

... Synopsis ...

Increasingly diffluent southwest flow will overspread the Southern
and Central Plains on Saturday as the midlevel pattern responds to a
strong shortwave trough/vorticity maximum moving into the Southwest.
This will induce strong southerly winds across the Plains, helping
to quickly draw an old frontal boundary northward. This boundary
should be oriented from northwest to southeast across portions of
Oklahoma by late Saturday.

... Portions of Kansas, Oklahoma, and western Arkansas ...

Most of the day should be devoid of thunderstorms as mid-level
heights rise downstream of a digging trough across the Southwest. At
the same time, strong southerly winds will transport Gulf moisture
northward from the far Southern Plains into the Central Plains.
Diurnal heating of this airmass will result in the development of
strong instability across much of the area, as maximum SBCAPE values
approach 4000 J/kg across portions of north Texas into central
Oklahoma.

During the late evening a subtle perturbation within the southwest
flow is forecast to approach Oklahoma. In response to this, the
low-level jet is forecast to increase to between 30 and 40 knots. As
it crosses the northward moving warm front, this warm-air
advection/isentropic ascent will combine with modest large-scale
ascent from the approaching midlevel perturbation to support
scattered thunderstorm develop on the north side of the moisture
gradient. Although differences exist between the various models, the
generic depiction of forecast soundings show long hodographs with
varying degrees of low-level curvature in the presence of 2000-3000
J/kg of MUCAPE. Thus, any storm that develops within the environment
will be capable of producing all hazards initially. With time,
thunderstorms should grow upscale into one or more southeast moving
bowing segments capable of producing damaging winds with perhaps a
QLCS tornado threat.

... North Texas into Southern Oklahoma ...

Diurnal heating of a moist airmass to the east of a dryline will
result in an extremely unstable airmass developing by the afternoon.
Although the region will be devoid of large-scale forcing for
ascent, temperatures in the 90Fs to the west of the dryline may be
sufficient to induce dryline circulations capable of initiating
isolated thunderstorms. Any thunderstorm that develops will be
capable of producing very large hail.

..Marsh.. 04/23/2026

$$

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ACUS03 KWNS 231931
SWODY3
SPC AC 231930

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0230 PM CDT Thu Apr 23 2026

Valid 251200Z - 261200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM
SOUTH-CENTRAL KANSAS INTO CENTRAL/EASTERN OKLAHOMA AND FAR NORTHWEST ARKANSAS...

...SUMMARY...
Severe thunderstorms will likely develop across portions of Oklahoma
and Kansas during the late afternoon and evening. These storms will
pose a risk of very large hail, damaging winds, and a couple of
tornadoes. Isolated severe thunderstorms may also develop across
portions of Texas.

...Synopsis...
Increasingly diffluent southwest flow will overspread parts of the
southern and central Plains on Saturday, as the midlevel pattern
responds to a strong shortwave trough/vorticity maximum moving into
the Southwest. This will induce strong southerly winds across the
Plains, helping to draw an outflow-influenced frontal boundary
northward. This boundary is currently forecast to be oriented from
northwest to southeast across portions of Oklahoma by late Saturday.

...Parts of KS/OK/TX into the ArkLaTex and Lower MS Valley...
No changes have been made to the Enhanced Risk. Rich moisture, steep
midlevel lapse rates, and diurnal heating will result in strong
destabilization across parts of the southern Plains, with at least
moderate destabilization into parts of KS. Large-scale ascent will
be subtle at best during the day, but isolated storm development
will be possible by late afternoon in the vicinity of the diffuse
warm front extending from eastern OK into southern KS and vicinity.
Favorable deep-layer shear combined with the moderate to strong
buoyancy will favor initial supercell development, with a threat of
very large hail and potentially a couple tornadoes (especially near
the remnant boundary).

Some upscale growth will be possible into the evening, with
potential for an organized cluster or MCS to move southeastward
along the instability gradient towards parts of the ArkLaTex, and
potentially the lower MS Valley, before weakening. This evolution
could be accompanied by an increasing damaging-wind threat, along
with isolated hail and/or tornado potential with any embedded
supercells.

Farther south, a conditionally favorable environment will be in
place during the afternoon along/east of the effective dryline, from
southwest OK into TX. Despite the lack of notable large-scale
ascent, isolated storms may develop due to weakening CINH and
heating to convective temperatures. Any storms that can mature
within this environment could evolve into supercells with large to
very large hail potential. The Marginal Risk has been expanded
southwestward across TX, where some global and extended CAM guidance
shows a signal for sustained development during the late afternoon.

..Dean.. 04/23/2026

$$

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