775
ACUS01 KWNS 121248
SWODY1
SPC AC 121246

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0746 AM CDT Mon Oct 12 2026

Valid 121300Z - 131200Z

...NO SEVERE THUNDERSTORM AREAS FORECAST...

...SUMMARY...
No severe weather is forecast across the U.S. today and tonight.

...Synopsis and Discussion...
Early-morning satellite imagery shows a deep upper trough covering
much of the CONUS west of the Rockies. Several shortwave troughs are
embedded within this troughing, including one moving out of the
central High Plains towards NE and SD, one progressing through the
base of the trough towards southern CA, and one moving through
southern NV toward UT. Extensive upper ridging is in place
downstream across much of the central CONUS with another shortwave
trough moving off the East Coast.

Recent surface analysis reveals expansive ridging centered over AL
that extends through the OH Valley. This ridging is flanked by a
pair of surface lows, one just off the Delmarva Peninsula and the
other over central NE. The central NE low sits along a wavy frontal
zone that extends northeastward through another low in southeast MN
through western Upper MI and northwest Ontario.

Strong low-level moisture advection is anticipated from the Mid
MO/MS Valley into the Upper Midwest as the NE/SD shortwave trough,
and attending NE surface low, progress northeastward today. Warm
mid-level temperatures will prevent convection within the warm
sector, but elevated showers and thunderstorms are possible north of
the surface low, beginning across the eastern Dakotas during the
afternoon and continuing eastward across the Upper Midwest and into
the Upper Great Lakes. Small hail is possible with the strongest
storms.

Moist and moderately strong southwesterly flow aloft will persist
throughout eastern periphery the western CONUS troughing, aiding in
the development of isolated to scattered thunderstorms as the
southern NV shortwave trough continues northeastward today. Weak
buoyancy should temper overall storm strength, although a strong
gusts or two is possible with the deepest storms.

Low-level confluence could support afternoon thunderstorms within
the moist return flow from the TX coast into central TX. Weak shear
should moderate storm severity. Isolated afternoon and evening
thunderstorms are possible along the weak lee troughing across the
southern High Plains as well. Limited buoyancy should temper updraft
strength and persistence.

..Mosier/Wendt.. 10/12/2026

$$