473 
ACUS48 KWNS 010736
SWOD48
SPC AC 010734

Day 4-8 Convective Outlook  
NWS Storm Prediction Center Norman OK
0234 AM CDT Fri May 01 2026

Valid 041200Z - 091200Z

...DISCUSSION...
...Days 4-6/Mon-Wed -- Southern Plains...Mid/Lower MS
Valley...Southeast...

An upper trough will develop southward across the northern Plains
and Upper Midwest on Monday. At the same time, another upper trough
will be oriented over southern CA and offshore over the Pacific. In
response to modest height falls and increasing westerly flow across
the Rockies, a lee low will develop over the central/southern High
Plains. Increasing southerly low-level flow will allow modified Gulf
moisture to return northward ahead of a dryline across the southern
Plains, and to the south of a cold front developing southward across
the central Plains and Upper MS Valley. Isolated strong to severe
thunderstorms will be possible within the narrow moist/warm sector
ahead of these surface boundaries, particularly the cold front
across parts of the MO/Mid-MS Valley, as capping may persist further
south across the Southern Plains. Given modest boundary moisture
with north and east extent across the Midwest, it is uncertain how
robust convection may be and where the most favorable area for
severe storms may develop, precluding 15 percent probabilities at
this time for Day 4/Mon. 

By Day 5/Tue, the jet associated with the eastward advancing
Southwest U.S. trough will being to phase with the upper trough over
the north-central U.S. This will bring strengthening southwesterly
flow to portions of the southern Plains and Mid-South vicinity while
southwesterly low-level flow continues to transport Gulf moisture
north/northeast ahead of a southeastward-advancing surface cold
front. The warm sector will become increasingly narrow toward the
Lower Ohio Valley, and any strong to severe thunderstorm potential
would likely focus from parts of Texas into Arkansas/far western
TN/KY. However, model guidance varies with regard to placement and
extent of potential convection ongoing Tuesday morning, which will
have implications for severe potential through the rest of the day.
Differences in the location of the surface front also add
uncertainty, precluding a 15 percent delineation.

Some strong to severe thunderstorm potential could persist into Day
6/Wed across parts of the Lower MS Valley and southeastern U.S. This
remains uncertain and will be influenced by convective evolution in
the days prior.

...Days 7-8/Thu-Fri...

The surface cold front is expected to move offshore the East Coast
on Day 7/Thu. Thunderstorm potential will continue ahead of the
front across the Southeast to the Mid-Atlantic, but severe potential
is uncertain as destabilization may be limited by widespread
rainfall and cloud cover. On Day 8/Fri, most of the CONUS will be
stable/dry behind the cold frontal passage. However, guidance
suggests a shortwave upper trough will approach the southern
Rockies/northern Mexico and surface cyclogenesis will maintain a
moist airmass across TX. If this occurs, some severe potential could
develop across parts of TX.

..Leitman.. 05/01/2026


File: /home/ldm/var/data/BY_SOURCE/KWNS/ACUS48/20260501T0736.txt