199
ACUS48 KWNS 080902
SWOD48
SPC AC 080900

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0400 AM CDT Mon Sep 08 2025

Valid 111200Z - 161200Z

...DISCUSSION...
The primary focus for isolated severe potential for the next several
days will be the upper low over the western US. The upper low is
forecast to slowly deepen late this week as it drifts eastward.
Shortwave ridging over the Plains is also forecast to move eastward,
gradually breaking down into this weekend. Surface high pressure
over the eastern US will allow modest return flow into the western
Plains along a lee trough and weak surface low over the Dakotas.
Sufficient destabilization is expected to support isolated
thunderstorms, and perhaps some severe risk, near the surface trough
as several shortwave perturbations within the southwesterly flow
ahead of the primary upper low move over the Plains. Somewhat
greater severe potential may develop this weekend as the upper low
ejects over the Plains and more robust moisture. However,the upper
trough may begin to weaken with the stronger flow aloft being
displaced north of the best moisture and buoyancy. While isolated
severe potential may exist each afternoon over the central and
northern Plains into early next week, confidence in widespread
severe potential remains too low for probabilities at this time.

..Lyons.. 09/08/2025