938
ACUS48 KWNS 180854
SWOD48
SPC AC 180852

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0352 AM CDT Mon Aug 18 2025

Valid 211200Z - 261200Z

...DISCUSSION...
...Thursday/Day 4 to Saturday/Day 6...
On Thursday, a subtle shortwave trough is forecast to move eastward
across the northern Plains. An axis of moderate instability will
likely develop by afternoon ahead of the front across the eastern
Dakotas and northwest Minnesota. Scattered storms could develop
during the afternoon near the instability axis, with an isolated
severe threat possible.

On Friday, the front is forecast to move southeastward toward the
upper Mississippi and mid Missouri Valleys, as an axis of
instability develops during the afternoon. Isolated thunderstorms
will be possible near the instability axis, but the severe potential
is expected to remain localized, mostly due to minimal convective
coverage.

On Saturday, the front is forecast to move across the Great Lakes
region, extending west-southwestward into the central U.S. Isolated
storms with a potential for localized severe will again be possible
in the afternoon ahead of the front. Due to a lack of large-scale
ascent, cell coverage is expected to be very isolated.

...Sunday/Day 7 and Monday/Day 8...
From Sunday into Monday, an upper-level trough and an associated
cold front is forecast to move across the eastern U.S. Thunderstorm
development will be possible ahead of the front Sunday afternoon in
the central Appalachians, and along parts of the middle to upper
Atlantic Seaboard on Monday afternoon. Instability ahead of the
front is expected to remain weak in most areas during this period,
suggesting any severe threat will remain localized.

..Broyles.. 08/18/2025