239
ACUS01 KWNS 020543
SWODY1
SPC AC 020542

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1242 AM CDT Tue Sep 02 2025

Valid 021200Z - 031200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY...

...SUMMARY...
Thunderstorms with potential for isolated severe wind gusts and hail
will be possible today across parts of the northern Plains and upper
Mississippi Valley.

...Northern Plains/Upper Mississippi Valley...
North-northwesterly mid-level flow will continue across the Great
Plains today, as a shortwave trough moves into the upper Mississippi
Valley. At the surface, a cold front will advance southeastward
across the northern Plains and upper Mississippi Valley. Ahead of
the front, surface dewpoints in the lower to mid 60s F will
contribute to the development of moderate instability by afternoon.
As surface temperatures warm and low-level convergence becomes
maximized along and ahead of the front, scattered convective
initiation will be likely during the mid to late afternoon.
Thunderstorms are expected to form and move southeastward across
eastern South Dakota and central to southern Minnesota. Most late
afternoon forecast soundings across that area by late afternoon have
0-6 km shear around 25 knots, with steep lapse rates between the
surface and 850 mb. This should be sufficient for a marginal severe
threat. The stronger multicells could be associated with isolated
severe wind gusts and hail.

..Broyles/Thornton.. 09/02/2025

$$