ACUS02 KWNS 270639
SWODY2
SPC AC 270637

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1237 AM CST Sat Dec 27 2025

Valid 281200Z - 291200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN MO/AR TO THE
OH AND TN VALLEYS...

...SUMMARY...
A low-probability severe thunderstorm threat is forecast from Sunday
afternoon into Sunday night from Missouri-Arkansas into the Ohio and
Tennessee Valleys.

...MO/AR to the OH/TN Valleys...
Phasing of multiple shortwave impulses will support amplification of
an upper trough, mainly on Sunday night, as it progresses from the
High Plains to the Great Lakes. This will induce deepening of a
surface cyclone from the Lower MO Valley towards Lake Huron.
Attendant cold front will accelerate Sunday night as it quickly
sweeps east into the Upper OH Valley and south into the northwest
Gulf by 12Z Monday.

Isolated to scattered elevated thunderstorms are most likely on
Sunday morning across parts of the Mid-MS Valley to the southern
Great Lakes within a strengthening low-level warm conveyor. It is
plausible that a few updrafts might weakly rotate, but meager
buoyancy atop the stable surface and cluster convective mode appears
supportive of only small hail.

Primary forecast challenge is the degree of surface-based
destabilization by Sunday afternoon, which will largely influence
tornado and severe thunderstorm wind potential. Latest guidance
remains split into two paths. This evening's RRFS/RAP/HRRR/HRW-ARW
suggest that a plume of meager buoyancy with MLCAPE up to 500 J/kg
should become established ahead of a cold front across the Ozarks to
a portion of the Mid-MS Valley near the surface cyclone by
afternoon. Meanwhile the NAM and HRW-NSSL indicate little to no
surface-based buoyancy in the warm-moist sector along the front.
Guidance consensus does suggest at least a low-topped, thin QLCS
should become established along the front from IL/IN towards AR by
early evening.

The progressive nature of the front along with the paucity of
surface-based instability downstream renders large uncertainty in
whether lightning-producing convection will be maintained Sunday
night along the front. However, kinematic fields will become
increasingly impressive, with strong gusts likely accompanying
low-topped convection along the front. CAM consensus though is for
convection to wane early morning Monday as instability remains
negligible. As such, have maintained the prior level 1-MRGL risk for
wind, with a subset of low tornado probabilities from MO to IN.

..Grams.. 12/27/2025

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

ACUS02 KWNS 260533
SWODY2
SPC AC 260531

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1131 PM CST Tue Nov 25 2025

Valid 271200Z - 281200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Isolated thunderstorms are possible across southeast Florida on
Thursday. Severe storms are not expected.

...Synopsis...
A broad mid-level trough will deepen across the eastern CONUS,
ushering in surface high pressure and associated cool and stable air
across most of the CONUS, limiting thunderstorms over most locales
tomorrow (Thursday). The one exception will be the southern FL
Peninsula tomorrow afternoon and evening. Here, a surface cold front
will sweep across the region, lifting a moist and buoyant low-level
airmass before moving offshore. Isolated thunderstorms are possible
during the afternoon hours, before the cold front clears moisture
from the region.

..Squitieri.. 11/26/2025

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

ACUS02 KWNS 120601
SWODY2
SPC AC 120559

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1159 PM CST Thu Dec 11 2025

Valid 131200Z - 141200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Isolated weak thunderstorm activity is possible across South Florida
and the Keys Saturday afternoon into Saturday night.

...Synopsis...
The large-scale pattern on Saturday will feature a ridge across the
western CONUS with troughing across the east. This mid-level trough
will amplify on Saturday as a strong mid-level jet streak moves from
the northern Plains to the Midwest. At the surface, a cold front
will sharpen from the Ohio Valley to the Plains and move south
rapidly Saturday evening.

...South Florida...
Tropical moisture will start to advect northward across the southern
Florida Peninsula on Friday. If this advects far enough north during
the day, a few thunderstorms may be possible on the eastern sea
breeze. During the overnight period, storm chances will increase
across the western Florida Peninsula as a mid-level shortwave trough
traverses the Gulf. Limited instability should preclude any severe
weather threat from this activity.

Shallow convection may develop along the southward moving cold front
from southeast Texas to central Alabama late Saturday night, but
warm temperatures aloft should limit lightning potential.

..Bentley.. 12/12/2025

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

ACUS02 KWNS 070702
SWODY2
SPC AC 070700

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
0100 AM CST Wed Jan 07 2026

Valid 081200Z - 091200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE
SOUTHERN PLAINS/ARKLATEX INTO THE LOWER/MID MS VALLEY...

...SUMMARY...
Isolated severe storms are possible on Thursday from Oklahoma into
parts of the ArkLaTex and lower/mid Mississippi Valley.

...Southern Plains into parts of the ArkLaTex and lower/mid MS Valley...

A negative-tilt mid/upper-level shortwave trough and associated
surface low will move quickly northeastward from the southern High
Plains towards the Great Lakes on Thursday. This shortwave will
impinge upon increasing low-level moisture and MUCAPE of near/above
500 J/kg from late D1/Wednesday into early D2/Thursday morning,
resulting in thunderstorm development. Deep-layer shear will be
quite favorable, and the strongest morning storms may be capable of
producing localized severe gusts and perhaps some hail. The Marginal
Risk area has been expanded westward across OK and southern KS, with
recent guidance indicating a slightly slower shortwave timing. Most
guidance suggests morning convection may remain slightly elevated,
but low tornado probabilities may eventually be needed if confidence
increases in surface-based storm development from central OK into
southeast KS.

With time, the morning storms will encounter decreasing buoyancy,
but if organized convection can be sustained, then some threat for
localized damaging wind could spread toward the mid MS Valley and
possibly a larger portion of the Midwest and lower OH Valley, in
conjunction with the ejecting shortwave. The northeast extent of
severe potential remains uncertain, with the shortwave expected to
eventually outpace returning low-level moisture.

Farther south, severe potential becomes more conditional from parts
of the ArkLaTex into the Mid-South, with stronger ascent expected to
remain north of this region. While buoyancy will remain weak,
low-level and deep-layer shear will be strong. Guidance remains
inconsistent regarding the development of deep convection in this
region, with the ECMWF and RRFS being somewhat more aggressive,
while other guidance is generally more muted. If robust convection
can develop within this environment, then some threat for locally
damaging wind and possibly a tornado could evolve from late
afternoon into part of Thursday night.

...Arizona...
Thunderstorm potential is expected to increase through the day
across parts of AZ, as a midlevel shortwave trough moves
east-southeastward across the region. Gusty winds and/or small hail
could occur with the strongest convection, though buoyancy is
currently expected to remain too meager for an organized severe
threat.

..Dean.. 01/07/2026

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