474
ACUS48 KWNS 010817
SWOD48
SPC AC 010816

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0316 AM CDT Mon Sep 01 2025

Valid 041200Z - 091200Z

...DISCUSSION...
A pronounced mid-level trough will gradually advance eastward across
the eastern U.S. through the remainder of the week into this
weekend, with multiple embedded mid-level perturbations expected to
pivot around the upper trough. The upper trough and associated
impulses will reinforce surface high pressure and cooler air across
much of the U.S. between the Mississippi River and Appalachians
through the extended forecast period. The surface cold front will
encounter seasonably rich low-level moisture while encroaching on
the Eastern Seaboard, prompting the development of at least
scattered thunderstorms. At the moment, the best chance for strong
storms, perhaps accompanied by an isolated severe threat, will be
along the central and northern Appalachians into the Mid Atlantic
within the Days 4-6 (Thursday-Saturday) time frame.

Meanwhile, as surface high pressure builds over the OH/TN Valley
regions, and the Interior West, seasonal moisture return is expected
across parts of the southern Plains due to surface lee troughing.
The aforementioned impulses pivoting around the broader scale upper
trough may graze the southern Plains, perhaps promoting enough
vertical wind shear atop a moist low-level airmass to support
isolated severe thunderstorms Days 4-6 (Thursday-Saturday).

..Squitieri.. 09/01/2025