708
ACUS48 KWNS 040904
SWOD48
SPC AC 040903

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0403 AM CDT Mon Aug 04 2025

Valid 071200Z - 121200Z

...DISCUSSION...
...Thursday/Day 4 to Saturday/Day 6...
During the late week time-frame, a mid-level trough is forecast to
develop over the Pacific Northwest and move eastward into the
northern Plains. As the system approaches, a moist and unstable
airmass is forecast across the northern Plains and upper Mississippi
Valley. On Thursday, a lead shortwave trough is forecast to move
across the northern Plains. Large-scale ascent associated with the
trough could result in a cluster of storms with an isolated severe
threat from Thursday evening into the overnight period. Isolated to
scattered thunderstorms may again develop Friday afternoon and
evening, as the exit region of a mid-level jet moves across the
northern Plains. As instability becomes maximized on Friday
afternoon, a severe threat will be possible across parts of the
Dakotas and Minnesota. Large hail and severe gusts will be the
primary threats. The models are in reasonably good agreement on the
timing of the mid-level system. For this reason, have added a 15
percent into the northern Plains to coincide with the projected
locations of the instability axis and mid-level jet.

On Saturday, the mid-level trough is forecast to move into the
northern Plains, as a belt of southwesterly flow shifts eastward
across the Upper Midwest. Thunderstorm development will be possible
in the afternoon and evening, to the east of a front within an
unstable airmass in the upper Mississippi Valley. Moderate
deep-layer shear will again support an isolated severe threat across
the region.

...Sunday/Day 7 and Monday/Day 8...
The front is forecast to move southeastward into the upper
Mississippi Valley on Sunday. This will favor thunderstorm
development along a corridor from Iowa northeastward into Wisconsin,
where an isolated severe threat will be possible in the afternoon
and evening. On Monday, forecasts suggest the instability axis will
remain in a similar location. For this reason, a severe threat could
again affect this same corridor. Due to the extended range in the
forecast, there is some uncertainty concerning this scenario early
next week.

..Broyles.. 08/04/2025