322
ACUS03 KWNS 311930
SWODY3
SPC AC 311929

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0229 PM CDT Sun Aug 31 2025

Valid 021200Z - 031200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
Strong thunderstorms are possible across parts of the northern
Plains, Upper Midwest, and lower Mississippi Valley on Tuesday,
though severe potential is uncertain.

...Parts of the northern Plains/Upper Midwest...
Within a broader northwesterly flow regime, a vigorous
mid/upper-level shortwave trough is forecast to move southeastward
from northern SK into MB on Tuesday, and approach northern ND/MN by
the end of the period. This shortwave and attendant large-scale
ascent will eventually impinge upon a zone of favorable
boundary-layer moisture and moderate instability along/ahead of a
cold front from parts of the Dakotas into MN. However, guidance
continues to vary regarding the timing of the shortwave and related
mid/upper-level jet, placement of the cold front by late afternoon,
and extent to which stronger deep-layer shear overspreads the more
favorable instability.

There will be some potential for storm development along/ahead of
the front during the afternoon and evening, and also for elevated
convection behind the front. A few strong storms (both elevated and
surface-based) will be possible, and severe probabilities may be
needed once confidence increases regarding the evolution of the
primary synoptic features.

...Lower MS Valley into parts of the TN Valley...
Scattered thunderstorms are possible during the afternoon and
evening across parts of the lower MS Valley into parts of the TN
Valley, within a modest west-northwesterly flow regime. A
low-amplitude shortwave approaching the base of a deep
mid/upper-level trough covering the eastern CONUS may locally
enhance ascent and deep-layer shear, and gusty winds could accompany
the strongest storms. However, midlevel lapse rates are expected to
remain quite weak, and updrafts may not become sufficiently strong
to support an organized severe threat.

..Dean.. 08/31/2025

$$