Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0759 PM CDT Sun Sep 21 2025

Valid 220100Z - 221200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE
SOUTHERN PLAINS INTO THE OZARKS...AND ALSO FROM SOUTHEAST SD INTO
SOUTHERN MN AND NORTHERN IA...

...SUMMARY...
Isolated large hail and severe gusts remain possible with storms
this evening across parts of the southern Plains into the Ozarks.
Other strong to locally severe storms may continue through the
evening from southeast South Dakota into southern Minnesota and
northern Iowa.

...North Texas into the Ozarks...
Storms have generally diminished in coverage and intensity this
evening across north Texas, due to increasing MLCINH and warming
midlevel temperatures (as noted in regional 00Z soundings), though a
favorably veering wind profile and steep lapse rates below 500 mb
will continue to support potential for an isolated supercell or two
and an attendant threat of hail and strong to severe gusts, for as
long as vigorous convection persists this evening. 

Farther northeast, a modest southwesterly low-level jet may help to
maintain storms into late tonight from eastern OK into northwest AR.
Moderate MUCAPE and marginally sufficient deep-layer shear could
support localized strong/damaging gusts and marginal hail with the
strongest storms. 

...Southeast SD into southern MN/northern IA...
Isolated cells have produced sporadic severe hail across parts of
southern MN late this afternoon into the early evening, to the south
of a mid/upper-level cyclone over central MN. Some redevelopment
remains possible this evening, within a modest low-level warm
advection regime. Relatively cool temperatures aloft, moderate
buoyancy, and effective shear of 25-35 kt will continue to support
potential for occasionally organized cells with an isolated hail
threat. Some clustering is possible late tonight, which could be
accompanied by locally gusty winds, but increasing low-level
stability may temper the damaging-wind threat.

..Dean.. 09/22/2025