919
ACUS48 KWNS 310844
SWOD48
SPC AC 310842

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0342 AM CDT Sun May 31 2026

Valid 031200Z - 081200Z

...DISCUSSION...
...Wednesday/Day 4 to Friday/Day 6...
A mid-level trough is forecast to move into the northern High Plains
on Wednesday, into the upper Mississippi Valley on Thursday and into
the Great Lakes on Friday. A moist and unstable airmass is forecast
over the northern Plains, where a severe threat will be possible
during the afternoon and evening on both Wednesday and Thursday.
Large hail and severe wind gusts would be possible. The threat is
forecast to be concentrated ahead of a cold front passing through
the northern Plains. Considerable uncertainty exists concerning the
timing of the front.

In the wake of the trough, a shortwave ridge is forecast to move
into the northern Plains on Friday. Isolated severe storms will
again be possible across the Dakotas Friday afternoon within an
unstable airmass, but limited forcing would keep any severe threat
more localized.

Further south across the southern and central Plains, a relatively
broad corridor of moderate instability is forecast each afternoon
from Wednesday to Friday. However, forcing is expected to remain
limited, which should keep any severe threat isolated and
conditional.

...Saturday/Day 7 and Sunday/Day 8...
On Saturday and Sunday, a mid-level trough is forecast to move
eastward into the northwestern U.S., as a shortwave ridge moves from
the Great Plains into the Mississippi Valley. In the wake of the
ridge, a secondary trough is forecast to move through the southern
and central Plains. Isolated severe storms would be possible near
this trough in the afternoon and evening on both Saturday and
Sunday. However, the timing of the trough and distribution of
instability surrounding the trough is considerably uncertain at this
time.

..Broyles.. 05/31/2026