Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0655 AM CST Wed Nov 11 2026

Valid 111300Z - 121200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF
EASTERN ILLINOIS INTO INDIANA...WESTERN/CENTRAL KENTUCKY...AND
MIDDLE TENNESSEE...

...SUMMARY...
Thunderstorms capable of producing isolated hail, damaging winds,
and perhaps a tornado may occur this afternoon and evening across
parts of eastern Illinois into Indiana, western/central Kentucky,
and middle Tennessee.

...Midwest/Lower Ohio Valley into Middle Tennessee...
Recent water vapor satellite imagery shows a mid-level shortwave
trough digging southeastward over the Upper Midwest towards the mid
MS Valley, with recent elevated thunderstorm development noted over
eastern IA capable of producing small hail (reference ~300 J/kg
MUCAPE in the 12Z observed DVN sounding). A related weak surface low
will develop from southeast IA this morning to the IN vicinity by
late afternoon/early evening. A trailing cold front will continue
advancing east-southeastward across the southern Plains, mid MS
Valley/Mid-South, and lower OH Valley this afternoon and evening.
The main uncertainty and likely limiting factor to severe potential
today remains shallow/limited low-level moisture ahead of the front
across the Midwest/lower OH Valley, where latest surface
observations show dewpoints generally in the 30s to mid 40s.
Somewhat greater low-level moisture associated with a modified
continental polar airmass is present across the southern Plains into
the Ozarks/lower MS Valley. But, west-northwesterly low-level flow
noted in area VWP trends and forecast low-level trajectories suggest
this moisture will struggle to advect northward through the day,
perhaps reaching parts of middle TN/southern KY. Therefore, most
guidance appears a bit moist with boundary-layer dewpoints and
related instability this afternoon, although some mid-level
moistening could occur.

Current expectations are for surface-based thunderstorms to
initially develop over eastern IL by 18-21Z, with additional
development possible with southward extent along/ahead of the front
in western/central KY through the afternoon/early evening as the
boundary layer gradually destabilizes. The combination of weak, but
potentially sufficient, MLCAPE and 30-40 kt of deep-layer shear
oriented largely orthogonal to the surface cold front should support
updraft organization. A mix of clusters and marginal supercells are
expected to evolve and spread quickly eastward while posing an
isolated threat for hail and damaging winds given cold mid-level
temperatures and modestly steepened low-level lapse rates. However,
the lack of greater low-level moisture/stronger instability should
tend to limit the overall severe threat. Modestly enhanced low-level
shear may also support a tornado risk, especially if a supercell can
develop and be sustained. But, tendency for low-level flow to veer
to westerly should reduce effective SRH with time through the late
afternoon/evening. The isolated severe risk should wane this evening
with eastward extent across the lower OH Valley as instability
diminishes with the loss of daytime heating.

...Central/Southern Florida Peninsula...
Isolated to scattered thunderstorms should preferentially form along
the Atlantic Coast sea breeze this afternoon across the
central/southern FL Peninsula. Glancing large-scale ascent
associated with a weak mid-level perturbation over the Southeast
should aid this convective development, but multiple inversions
aloft noted in the 12Z observed MFL/TBW soundings should tend to
limit updraft intensities. Still, small hail and gusty winds could
occur with the stronger cores given the presence of moderate
instability and 30-35 kt of deep-layer shear.

..Gleason/Wendt.. 11/11/2026

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
1030 AM CST Wed Nov 11 2026

Valid 111630Z - 121200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE LOWER OHIO AND WESTERN TENNESSEE VALLEYS...AS WELL AS ACROSS THE
EAST-CENTRAL FLORIDA PENINSULA...

...SUMMARY...
Thunderstorms capable of producing isolated hail, damaging winds,
and perhaps a tornado may occur this afternoon and evening across
parts of eastern Illinois into Indiana, western/central Kentucky,
and middle Tennessee. Isolated severe thunderstorms are also
possible across the east-central Florida Peninsula.

...Midwest/Lower Ohio Valley into Middle Tennessee...
Recent satellite imagery shows a lead shortwave trough moving into
northern IL, with another shortwave trough farther back northwest
moving into the Mid MO Valley. Showers and thunderstorms are ongoing
near the lead shortwave. Thunderstorm intensity has decreased over
the last half hour or so as these storms move into an environment
with less elevated buoyancy (as observed by the 12Z ILX sounding).
The lead shortwave is forecast to continue eastward into the OH
Valley while the second shortwave continues more southeastward into
the Lower OH Valley vicinity. The surface low currently over the
IA/IL border vicinity is forecast to progress eastward with the lead
wave while an attendant cold front sweeps southeastward through the
mid MS Valley/Mid-South, and lower OH Valley this afternoon and
evening.

Increasing low-level moisture is anticipated ahead of this front,
advecting northeastward into the region from the Ozarks/Mid-South
region. Recent surface analysis shows the mid 50s dewpoints are
still in northern AR, so there is some question as to how far
northeastward the greater low-level moisture will reach before
frontal passage. Current expectation is for the best overlap between
low-level moisture (and associated buoyancy) with the stronger
large-scale ascent will occur across southern IN and adjacent
western KY. Here, the combination of weak buoyancy (i.e. MLCAPE
around 500-800 J/kg) and 30-40 kt of deep-layer shear
oriented largely orthogonal to the surface cold front should support
a mix of bowing clusters and supercells. Isolated hail and damaging
gusts will be the primary risks. Hail is more likely with any more
cellular activity and damaging gusts more likely with any
fast-moving bowing segments. Modestly enhanced low-level
shear may also support a low-probability tornado risk, but a
tendency for low-level flow to veer to westerly should reduce
effective SRH with time through the late afternoon/evening. The
isolated severe risk should diminish with eastward extent this
evening across the lower OH Valley as front outruns the low-level
moisture and daytime heating wanes.

...Central/Southern Florida Peninsula...
Isolated to scattered thunderstorms are expected across the 
central/southern FL Peninsula this afternoon. Glancing large-scale
ascent associated with a weak mid-level perturbation over the
Southeast should aid this convective development. A warm layer
around 700 mb could limit overall buoyancy, but 500 mb temperatures
will be around -9 to -11 deg C and most forecast sounding still show
1500+ J/kg of uninhibited MLCAPE this afternoon. Moderate deep-layer
shear will exists across the region as well. These conditions appear
supportive of marginally severe hail and gusty winds within the
stronger cores, which appear most probable along the east-central FL
Coast.

..Mosier/Halbert-K.. 11/11/2026

Day 1 Fire Weather Outlook  
NWS Storm Prediction Center Norman OK
1017 AM CST Wed Nov 11 2026

Valid 111700Z - 121200Z

...NO CRITICAL AREAS...

The forecast remains on track with reduced fire weather concerns
across the CONUS today. Please see previous discussion for more
details.

..Williams.. 11/11/2026

.PREV DISCUSSION... /ISSUED 1122 PM CST Tue Nov 10 2026/

...Synopsis...
The upper-level flow over the CONUS will continue to amplify with
ridging over the Intermountain West and troughing over portions of
the central/eastern US. A surface cyclone will strengthen and track
east-southeast across the Midwest into the Upper Ohio Valley. Drier
pre-frontal conditions are likely across portions of the southern
Appalachians into Georgia and South Carolina. However, there will
likely be limited overlap of moderately receptive fuels and elevated
winds/RH, thus precluding introducing any risk areas at this time.
Drier post-frontal northwesterly flow is expected on the Plains as
well, but the strongest winds (15-20 mph sustained) are likely to be
displaced from the lowest RH (20-25%), with limited receptive fuels.

...Please see www.spc.noaa.gov/fire for graphic product...