RSS Mesoscale Discussions from Storm Prediction Center
SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0126 AM CDT Sat May 02 2026
Valid 041200Z - 051200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE MIDWEST...
...SUMMARY...
Strong to severe thunderstorms are possible across portions of the
Midwest late Monday afternoon into Monday night.
...Eastern KS to OH...
A deepening upper trough will develop southward into the Upper
Midwest on Monday/Monday night. Stronger height falls will remain
confined to the Upper Midwest/Great Lakes vicinity, with more modest
height falls into the Mid-MS Valley near/after 00z. At the surface,
low pressure is forecast to move across Ontario and Quebec, while a
trailing cold front develops southward across the Upper MS Valley
during the day, and becomes oriented from southern Lower MI to
eastern KS by early Tuesday. Gulf moisture return will remain
limited, with generally 50s to near 60 F dewpoints expected in a
narrow corridor ahead of the cold front. Cool temperatures aloft
will support steep lapse rates across the region and MLCAPE around
1000-1500 J/kg is forecast during the afternoon into the nighttime
hours from KS into portions of the Mid-MS Valley and eastward into
IN/OH/extreme southern Lower MI.
Capping and weak forcing for ascent may limit thunderstorm
development across the warm sector through peak heating. However, as
a southwesterly low-level jet increases around/after 00z, modest
height falls overspread the region, and the surface cold front
develops southward toward the corridor of modest boundary layer
moisture, isolated to scattered thunderstorms may initiate.
Effective shear around 35+ kt will aid in organized storm
structures, and isolated large hail and locally strong gusts are
possible.
..Leitman.. 05/02/2026
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Day 4-8 Outlook
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0255 AM CDT Sat May 02 2026
Valid 051200Z - 101200Z
...DISCUSSION...
...Days 4-5/Tue-Wed -- Southeast OK/ArkLaTex to Lower MS/TN
Valleys...
Southwesterly deep-layer flow will increase from the southern
Rockies to the Mid-South on Day 4/Tuesday as a southern stream
shortwave trough over the Southwest merges with an upper trough over
the Plains/Upper Midwest. At the surface, low pressure will develop
over the southern Plains and slowly progress east in AR as a cold
front develops southeast across OK/AR and the Lower OH Valley. Ahead
of the front, rich Gulf moisture will return northward, and 60s to
near 70 F dewpoints are forecast by Tuesday afternoon/evening across
southeast OK and the ArkLaTex. Timing of thunderstorm development is
a bit uncertain as shortwave ridging may overspread the southern
Plains vicinity through afternoon. However, forcing for ascent
should increase with the approach of the surface front and as a
low-level jet increasing Tuesday evening. Moderate instability and
strong vertical shear should support severe thunderstorm activity
near the cold front from late afternoon into Tuesday night.
On Day 5/Wednesday, the Plains upper trough will migrate east,
extending from the Upper Great Lakes to the Lower MS Valley by early
Thursday. The surface cold front will extend from the OH Valley into
north/central TX Wednesday morning and slowly progress southeast
through the period. Gulf moisture will return north and east across
the southern U.S. ahead of the front. While deep-layer flow will
largely be parallel to the surface front, moist and unstable airmass
ahead of the front should support some risk for severe
thunderstorms.
...Days 6-8/Thu-Sat...
A deepening surface low will develop northward across the
Mid-Atlantic and Northeast on Thursday as a surface cold front
continues to shift east across much of the eastern U.S. While a
moist airmass will be in place across parts of the Southeast to the
Mid-Atlantic, it is uncertain how much destabilization will occur
due to possibly widespread thunderstorm activity and cloud cover
(particularly from the Mid-Atlantic northward). Large-scale ascent
will become increasingly displaced to the north across the
Southeast, and convection may tend to be anafrontal. Trends will be
monitored and severe probabilities could become necessary for parts
of the eastern U.S. on Thursday in later outlooks.
Severe potential will be limited on Friday as the prior cold frontal
passages clears out Gulf moisture and surface high pressure envelops
much of the eastern half of the U.S. Weak upper troughing could
overspread the Rockies and High Plains by the end of the period,
allowing for Gulf moisture return across the Plains and an increase
in thunderstorm potential.
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