089
ACUS03 KWNS 131926
SWODY3
SPC AC 131925

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0225 PM CDT Sun Sep 13 2026

Valid 151200Z - 161200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE CENTRAL
PLAINS TO THE GREAT LAKES...

...SUMMARY...
Scattered strong thunderstorms may impact a corridor south to
southwest of the Great Lakes through the lower Missouri Valley
Tuesday afternoon and evening, accompanied by at least some risk for
locally damaging wind gusts.

...Discussion...
A mid-level trough will move into Ontario on Tuesday with the
mid-level ridge building in its wake across the Midwest and into the
Upper Midwest. Beneath this ridge, a cold front will move slowly
southeastward from southern Iowa and northern Kansas at the
beginning of the period, to northern Oklahoma to central Missouri by
the end of the period. Dewpoints will increase into the low to mid
70s south of the front with weak to moderate instability
anticipated. Forcing will be somewhat nebulous given the rising
heights aloft and weak convergence along the slow-moving, decaying
front.

Nonetheless, moderate to potentially strong instability and an
uncapped airmass should support some thunderstorms capable of severe
wind gusts. Some lingering 30 to 40 knot mid-level flow is forecast
to remain across portions of the warm sector Friday afternoon
(particularly across northern Illinois/Indiana) which may aid in
storm organization, but warm air aloft and a lack of clear supercell
mode should limit the overall hail threat.

..Bentley.. 09/13/2026

$$