ACUS01 KWNS 311226
SWODY1
SPC AC 311225

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0625 AM CST Wed Dec 31 2025

Valid 311300Z - 011200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Isolated thunderstorms are possible along coastal southern
California very late in the period.

...Southern CA...
A southern-stream upper-level trough will approach the southern CA
coast late tonight. Latest model guidance suggests increasing
large-scale ascent will approach the coast, contributing to isolated
convection along/ahead of a weak front as it surges inland,
primarily after 09z. Forecast soundings along the coast suggest
thunderstorms should be elevated in nature, with initial convection
likely rooted at or above 850mb. Weak buoyancy and shear suggests
minimal potential for severe storms prior to 12z Thursday.

..Bunting/Weinman.. 12/31/2025

$$
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* Origin: Capitol City Online (618:250/1)

ACUS01 KWNS 021258
SWODY1
SPC AC 021257

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0657 AM CST Fri Jan 02 2026

Valid 021300Z - 031200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

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

...Central Gulf Coast into the Southeast...
Early-morning satellite imagery shows a pair of shortwave troughs
moving within the broadly anticyclonic flow that covers much of the
CONUS. The easternmost shortwave is currently moving through eastern
OK and is forecast to continue progressing eastward throughout the
day, moving across the Mid-South and TN Valley. The westernmost
shortwave is currently moving into the Four Corners vicinity, with
continued southeastward progress anticipated throughout the day,
taking the wave through southern CO/northern NM, the TX Panhandle,
and OK/north TX. Recent surface analysis places a low over the
central TX/OK border region, with modest low-level moisture return
ongoing across the TX Gulf Coast and Lower MS Valley.

This low is forecast to progress gradually eastward in tandem with
its parent shortwave, ending the period over central AL. Broad
low-level moisture return will persist within the warm sector of
this low, with low to mid 60s dewpoints likely extending from
southern LA into central MS/AL by early tomorrow morning. Warm-air
advection across this warm sector is forecast to result in elevated
instability beginning in the late afternoon and persisting through
the evening and overnight. Elevated thunderstorms are anticipated
near the nose of the low-level jet where the warm-air advection will
be maximized. Moderate mid-level flow will extend across the region
and vertical shear will be strong enough to support storm
organization. However, weak buoyancy is expected to limit updraft
depth and persistence, keeping the overall severe potential low.

Some surface-based instability is possible very late in the period
(09Z-12Z Saturday) from southeast LA into the FL Panhandle. Even so,
limited forcing for ascent and weak buoyancy should temper the
overall severe potential here as well with the greater severe risk
occurring later and further downstream on Day 2 (Saturday).

...Northern/Central CA...
A deep cyclone, currently over the western Pacific Ocean, is
forecast to progress northeastward throughout the day as a series of
shortwave troughs rotate through its southern and eastern periphery.
One of these shortwaves is forecast to reach the northern
CA/southern OR coast by late tonight. Strong ascent and cooling
mid-level temperatures associated with this wave will support
showers and embedded thunderstorms across northern and central CA
tonight. The deepest convection is anticipated within a frontal band
forecast to reach the region between 04Z and 06Z. Robust wind fields
will accompany this shortwave as well, but the limited buoyancy
should temper the overall severe potential.

..Mosier/Bentley.. 01/02/2026

$$
--- SBBSecho 3.28-Linux
* Origin: Capitol City Online (618:250/1)

ACUS01 KWNS 071254
SWODY1
SPC AC 071253

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0653 AM CST Wed Jan 07 2026

Valid 071300Z - 081200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTHWEST
TEXAS INTO CENTRAL OKLAHOMA...

...SUMMARY...
Marginally severe storms are possible from late tonight into the
early morning on Thursday from parts of west and northwest Texas
northeastward into Oklahoma.

...Southwest TX into Central OK...
Early-morning satellite imagery shows a compact cyclone just off the
coast of the northern Baja Peninsula. This cyclone is forecast to
move quickly eastward across southern AZ/NM and northern Mexico
throughout the day today, devolving into an open wave. This wave
will likely pivot into a more negative tilt by early tomorrow as it
moves across the southern High Plains. Strong mid-level flow will
accompany this wave, spreading eastward/northeastward across much of
the southern Plains and Ozark Plateau.

Significant mass response, and associated airmass modification, will
occur across the southern Plains ahead of the this low, with the
low-level moisture (i.e. low 60s dewpoints) currently confined to
the TX Coastal Plain and South TX likely reaching southern OK by
early tomorrow. Expectation is for ascent attendant to the
approaching shortwave to interact with the northwestern periphery of
this moisture return during the last few hours of the period (i.e.
08Z-12Z Wednesday), resulting in elevated thunderstorms from
southwest TX into central OK. Buoyancy will be modest (i.e. MUCAPE
from 500 to 1000 J/kg), fostered by a combination of steepening
mid-level lapse rates and increased low to mid-level moisture.
Strong deep-layer vertical shear (i.e. 0-6 km bulk shear of 40 to 60
kt) will be in place as well, supporting the potential that some of
these thunderstorms are more robust/organized. Given the low-level
stability, primary risk with the more organized storms is likely
hail, but some isolated gusts maybe be strong enough to penetrate
the low-level stability as well.

...Pacific Northwest...
A strong shortwave trough is forecast to progress eastward through
the Pacific Northwest today, followed closely by another southeastward-progressing shortwave that moves into northern CA.
Cold mid-level temperatures will foster scant buoyancy, and the
frontal band associated with this lead wave will likely feature some
deeper convective elements capable of producing lightning.

..Mosier/Bentley.. 01/07/2026

$$
--- SBBSecho 3.28-Linux
* Origin: Capitol City Online (618:250/1)

ACUS01 KWNS 151217
SWODY1
SPC AC 151215

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0615 AM CST Thu Jan 15 2026

Valid 151300Z - 161200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
A few thunderstorms may affect south Florida this morning.

...South FL...
Morning water vapor imagery shows a persistent large upper trough
over the eastern states, with a significant shortwave trough digging southeastward over LA/MS. This feature will quickly rotate across
the Gulf and approach FL by early afternoon. Strong large-scale
ascent ahead of the feature could be sufficient for showers and
isolated thunderstorms in the moist and marginally unstable airmass
along/ahead of a cold front over far southern FL, the Straits, and
near-shore waters. This threat will end by early afternoon as the
front moves off the east coast. Poor mid-level lapse rates and
marginal instability should limit any severe threat.

..Hart/Kerr.. 01/15/2026

$$
--- SBBSecho 3.28-Linux
* Origin: Capitol City Online (618:250/1)

ACUS01 KWNS 211225
SWODY1
SPC AC 211224

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0624 AM CST Wed Jan 21 2026

Valid 211300Z - 221200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Isolated thunderstorms should occur across parts of east/southeast
Texas into the lower Mississippi Valley today and tonight.

...Synopsis and Discussion...
Modest low-level moisture will make some inland advancement today
across east/southeast TX into the lower MS Valley ahead of a surface
cold front as longwave upper troughing persists across the
central/eastern CONUS. A low-amplitude shortwave trough rounding the
base of the large-scale upper trough should continue to encourage
showers and isolated/mainly elevated convection across these areas
through tonight. Instability is expected to remain too weak to
support severe thunderstorms.

..Gleason/Dean.. 01/21/2026

$$
--- SBBSecho 3.28-Linux
* Origin: Capitol City Online (618:250/1)

ACUS01 KWNS 221232
SWODY1
SPC AC 221230

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0630 AM CST Thu Jan 22 2026

Valid 221300Z - 231200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Isolated thunderstorms will be possible across southeast Florida
today, but severe thunderstorms are not expected.

...Synopsis and Discussion...
Surface high pressure will remain dominant today across much of the
Plains into the MS/OH Valleys amid persistent upper troughing over
the central/eastern CONUS. As such, overall thunderstorm potential
should remain generally low, with perhaps a couple exceptions.
Isolated thunderstorms appear possible across parts of
coastal/southeast FL along/near a weak inverted surface trough amid
greater low-level moisture and modest buoyancy.

An upper low over the eastern Pacific should develop
south-southeastward through the period off the coast of southern
CA/northern Baja. Cool temperatures aloft may support weak MUCAPE
and very isolated lightning flashes with convection that should
remain mostly offshore this afternoon. Overall coverage of
thunderstorms appears less than 10% across coastal southern CA.

..Gleason/Dean.. 01/22/2026

$$
--- SBBSecho 3.28-Linux
* Origin: Capitol City Online (618:250/1)

ACUS01 KWNS 231238
SWODY1
SPC AC 231237

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0637 AM CST Fri Jan 23 2026

Valid 231300Z - 241200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Scattered weak thunderstorm activity is likely today into tonight
across the Texas Big Bend region into central Texas.

...Synopsis...
Early-morning satellite imagery shows a well-defined upper low off
the northern Baja California coast, with a subtle lead shortwave
moving into northwest Mexico and modest shortwave ridging from
central Mexico into southeast AZ/southwest NM. Largely zonal flow
persists across much of the central and eastern CONUS.

Surface analysis reveals an expansive 1048 mb high extending from
the southern Canadian Prairies through the central Plains, mid MS
Valley, and much of the OH Valley. Very cold temperatures accompany
this high, and an intense cold front is currently pushing southward
across the TX Panhandle, northern OK, and northern AR. This same
front is pushing southeastward across the middle OH Valley.

...Big Bend Region into North/Central Texas...
Some modest low-level moisture advection is ongoing ahead of the
cold front from the TX Coastal Plain into the TX Hill Country. This
advection is forecast to continue throughout the day, likely
bringing upper 50s/low 60s dewpoints as far northwest as the Edwards
Plateau before interacting with the front this afternoon. Heating
will be tempered by abundant cloud cover and mid-level lapse rates
will be poor. Even so, the anticipated low-level moisture coupled
with cold mid-level temperatures should result in a relatively
confined area of moderate buoyancy (i.e. MLCAPE 500-1000 J/kg)
tonight. Additionally, deep-layer vertical shear will be strong,
resulting in environmental conditions that could support a
strong/marginally severe storm or two. However, the overall threat
will be mitigated by the undercutting nature of the cold front and
likely storm interactions. The limited duration and isolated nature
of the severe threat currently precludes the need for probabilities.

Farther north and west, a large area of precipitation is expected to
develop behind the front, supported by the strengthening
southwesterly flow aloft and associated broad isentropic ascent.
Cooling mid-level temperatures may result in minimal buoyancy
(mostly after 03Z), with a few deeper convective elements within the precipitation shield capable of producing lightning amid freezing
rain and/or sleet.

..Mosier/Broyles.. 01/23/2026

$$
--- SBBSecho 3.28-Linux
* Origin: Capitol City Online (618:250/1)

ACUS01 KWNS 241245
SWODY1
SPC AC 241243

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0643 AM CST Sat Jan 24 2026

Valid 241300Z - 251200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

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

...Southern Plains/Lower MS Valley/Southeast...
Early-morning satellite imagery shows a well-defined upper low just
off the coast of the central Baja Peninsula. Deep southwesterly flow
aloft extends northeastward from this low across Mexico and the
southern Plains before joining the more confluent, single-stream southwesterlies in place from the MS Valley eastward.

A subtle shortwave trough is currently progressing northeastward
across central TX within the belt of stronger flow preceding the
upper low, contributing to some deeper convective cores over the
region. Expectation is for this shortwave to continue northeastward,
resulting in an expansion of precipitation downstream. Forecast
soundings do show some minimal buoyancy, supporting the potential
for some deeper convective cores capable of lightning. Highest
thunderstorm chances will be concentrated across southern LA, but
low probabilities also exist farther north where low-level profiles
will be cold enough for freezing rain and/or sleet.

The Baja upper low is forecast to progress eastward throughout the
day, moving across central Mexico and reaching central TX by early
tomorrow morning. Evolution of this low will encourage northeastward progression of a surface low along the surging arctic cold front.
This will take the low from its current location over deep south TX
quickly northeastward over the northwest Gulf basin, across southern
LA and to the central AL/MS border vicinity. Strong low-level
southerly flow is anticipated ahead of the upper low and associated
surface low as well, with this overall evolution contributing to
rapid airmass modification from the central Gulf Coast into central
AL and MS. Even with this modification, most forecast soundings
depict a boundary layer that does not recover adequately for
surface-based convection.

General expectation is for ascent attendant to this system to
support another round of precipitation beginning over east TX after
06Z before expanding northeastward with time. Some very modest
buoyancy is possible atop a strong warm noise, with isolated
elevated thunderstorms possible. This thunder potential includes
areas from east TX across northern/central LA into northern MS where
surface temperatures will be below freezing, suggesting some
lightning is possible with mixed winter precipitation.

...Southwest...
A shortwave trough is forecast to progress cyclonically from central
CA into AZ during the period. Cold mid-level temperatures combined
with ascent from the shortwave will support the potential for a few
isolated thunderstorms across central and southeast AZ and southwest
NM from the late afternoon through tonight.

..Mosier/Broyles.. 01/24/2026

$$
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* Origin: Capitol City Online (618:250/1)