353
ACUS02 KWNS 010551
SWODY2
SPC AC 010550

Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1250 AM CDT Mon Sep 01 2025

Valid 021200Z - 031200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE NORTHERN PLAINS INTO THE UPPER MIDWEST...

...SUMMARY...
Isolated severe thunderstorms are possible across parts of the
northern Plains into the Upper Midwest tomorrow (Tuesday).

...Synopsis...
Broad cyclonic mid-level flow will persist along the Eastern
Seaboard while upper ridging continues west of the Rockies, with the
central U.S. placed under a northwesterly upper-flow regime tomorrow
(Tuesday). A large and pronounced embedded mid-level shortwave will
quickly translate southeastward from Canada and overspread the Upper
MS Valley through the day, encouraging a surface cold front to surge
southward across the northern Plains and Upper Midwest.
Thunderstorms will develop ahead of the cold front, a few of which
may be severe.

...Northern Plains into the Upper Midwest...
Preceding the cold front will be a warm and seasonally moist
airmass, overspread by 6.5-7.5 C/km mid-level lapse rates, yielding
MLCAPE peaking in the 1500-2000 J/kg range by afternoon.
Strengthening northwest flow with height will also yield modestly
curved and elongated hodographs and 35+ kts of speed/effective bulk
shear. These conditions will favor the development of multicells and
perhaps a transient supercell with the stronger updrafts that manage
to form ahead of the cold front. Isolated severe gusts or instances
of hail are plausible, warranting the introduction of Category
1/Marginal risk severe probabilities this outlook.

..Squitieri.. 09/01/2025

$$