580
ACUS48 KWNS 070900
SWOD48
SPC AC 070858

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0358 AM CDT Sun Sep 07 2025

Valid 101200Z - 151200Z

...DISCUSSION...
The mid-level flow pattern across the US is forecast to become more
stagnant into the extended-range forecast period as the western US
upper low deepens and shortwave ridging over the Plains moves slowly
eastward. Broad troughing over the East should gradually
consolidate, slowing eastward progress of the upper ridge. As the
western trough slowly approaches the Rockies, a lee trough should
sharpen each afternoon with a narrow zone of moisture return along
and east into parts of the High Plains. Sufficient destabilization
is expected to support isolated thunderstorms, and perhaps some
severe risk, near the lee trough as smaller embedded perturbations
eject eastward periodically. However, with only slow movement of the
upper ridge expected, forcing for ascent should remain modest until
early next weekend. Somewhat greater severe potential may develop
D6/Friday or D7/Saturday as the primary upper trough begins to
emerge over the Plains. However, given the uncertainties associated
with the smaller scale features, and the timing of the main trough,
limited confidence exists regarding severe potential in the extended
forecast.

..Lyons.. 09/07/2025