RSS Mesoscale Discussions from Storm Prediction Center
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0652 AM CST Sun Jan 18 2026
Valid 181300Z - 191200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Severe thunderstorms are not forecast across the U.S. today or
tonight.
...Synopsis and Discussion...
Large-scale upper troughing will persist today over the central and
eastern CONUS. An embedded mid-level shortwave trough will pivot
quickly east-northeastward across the Deep South and Atlantic
Seaboard through this evening as a secondary/reinforcing cold front
advances southeastward across the remainder of the central Gulf
Coast states and FL Peninsula. Low-topped convection ongoing this
morning over the east-central Gulf will struggle to attain
sufficient height to support charge separation and lightning as it
approaches the west-central FL Peninsula (Tampa vicinity),
especially given the poor lapse rates and multiple stable layers
aloft observed in the 12Z TBW sounding. Generally 60s surface
dewpoints are in place this morning ahead of the front across south
FL and the Keys. As daytime heating occurs, adequate instability
should develop to support isolated thunderstorms over these areas.
Low-level flow will veer through the afternoon with the approach of
the cold front, and greater thunderstorm potential should eventually
focus offshore. With poor lapse rates aloft limiting updraft
strength, severe thunderstorms are not expected.
..Gleason.. 01/18/2026
Read more
Day 4-8 Outlook
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0245 AM CST Sun Jan 18 2026
Valid 211200Z - 261200Z
...DISCUSSION...
A large-scale upper trough will develop eastward across the Plains
and eastern U.S. on Days 4-5/Wed-Thu. As this occurs, some modest
Gulf moisture will spread across east TX toward the Lower MS Valley
ahead of a cold front. Some low potential for thunderstorms will be
possible, but the modest moisture return will limit instability and
severe potential is low.
Beyond Day 5/Thu, forecast guidance is not in very good agreement
with large spread resulting in greater than normal uncertainty. The
control member of the ECMWF appears to be an outlier, showing some
increasing severe potential across the Gulf Coast states toward the
end of the forecast period. However, the GFS and EC-AIFS keep any
Gulf moisture offshore, precluding severe potential. Given these
large model discrepancies, severe probabilities seem low for now.
Read more
