701
ACUS48 KWNS 130901
SWOD48
SPC AC 130859

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0359 AM CDT Fri Jun 13 2025

Valid 161200Z - 211200Z

...DISCUSSION...
...Monday/Day 4 to Wednesday/Day 6...
A mid-level ridge across the Great Plains is forecast to become less
amplified on Monday, as multiple shortwave troughs move through
westerly flow across the north-central states. A moist airmass is
forecast across much of the central and northern Plains, where
moderate to strong instability appears likely to develop by
afternoon. Along the northern edge of the stronger instability,
scattered convective initiation is expected. The instability,
combined with moderate deep-layer shear, should support a severe
threat. Large hail and severe wind gusts will be possible during the
afternoon and evening.

The mid-level ridge is forecast to move eastward into the Missouri
Valley on Tuesday, as a trough moves into the Rockies. At the
surface, a moist airmass is forecast from the central Plains into
the Missouri Valley, where moderate to strong instability appears
likely to develop by afternoon. Large-scale ascent ahead of the
approaching trough is forecast to move into the central Plains
Tuesday evening. As a result, a large area of thunderstorms is
forecast to develop from northern Kansas into much of Nebraska.
Model forecasts suggest that moderate deep-layer shear will be in
place, which would support a large hail and wind-damage threat.

The mid-level trough is forecast to move across the Great Plains on
Wednesday. A moist airmass is forecast to remain in place to the
east of the trough across the lower Missouri and Mississippi
Valleys. Ahead of the trough, moderate instability is forecast by
afternoon. Thunderstorm development is expected with this unstable
airmass from eastern Kansas northeastward into the mid to upper
Mississippi Valley. A severe threat will be possible. The greatest
potential for severe storms could be from northern Missouri into
southern Wisconsin, along and near the axis of a low-level jet.

...Thursday/Day 7 and Friday/Day 8...
From Thursday into Friday, the mid-level trough, and an associated
cold front, is forecast to move from the mid Mississippi Valley to
the Eastern Seaboard. A moist and unstable airmass should be in
place ahead of the trough. Thunderstorm development will be possible
along parts of the front, and across the warm sector. Although a
severe threat may develop as instability increases during the day,
the timing of the front remains questionable and predictability is
low.

..Broyles.. 06/13/2025