246
ACUS48 KWNS 090844
SWOD48
SPC AC 090843

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0343 AM CDT Sat May 09 2026

Valid 121200Z - 171200Z

...DISCUSSION...
...Tuesday/Day 4 and Wednesday/Day 5....
On Tuesday and Wednesday, northwesterly mid-level flow will be in
place over the central U.S. A shortwave trough is forecast to move
southeastward into the upper Mississippi Valley on Tuesday, and into
the central Appalachians on Wednesday. Isolated severe thunderstorms
will be possible ahead of the trough each day, but weak instability
should keep any severe threat marginal.

...Thursday/Day 6 to Saturday/Day 8...
On Thursday, a shortwave ridge is forecast to move eastward across
the central U.S. A north-to-south axis of instability is forecast to
develop in the wake of the ridge across the Great Plains. Isolated
severe storms will be possible along parts of this corridor Thursday
afternoon and evening.

On Friday, a subtle shortwave trough is forecast to move eastward
across the central U.S. Moderate deep-layer shear is forecast to be
in place over a moist and unstable airmass from eastern Kansas
southward into Oklahoma, where isolated severe storms may develop
during the afternoon and evening.

On Saturday, strong low-level moisture advection is forecast to
develop over the south-central U.S., as a mid-level shortwave trough
moves into the southern Plains. Near this trough, scattered
thunderstorm development will be possible. Moderate deep-layer shear
and instability should be favorable for an isolated severe threat
during the afternoon and evening, mainly from Oklahoma southward
into west-central Texas.

Considering the last few days of the Day 4 to 8 period, recent
models have shown substantial variability from run to run. Scenarios
have been outlined based on model consensus.  However, confidence is
low concerning potential outcomes, especially this upcoming weekend.

..Broyles.. 05/09/2026