359
ACUS01 KWNS 120540
SWODY1
SPC AC 120538
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1238 AM CDT TUE AUG 12 2025
VALID 121200Z - 131200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE UPPER
GREAT LAKES AND MIDWEST...AND PARTS OF THE SOUTHWEST...
..SUMMARY
STRONG THUNDERSTORMS MAY IMPACT PARTS OF THE UPPER GREAT LAKES
REGION. STORMS MAY BE ACCOMPANIED BY AT LEAST SOME RISK FOR SEVERE
WIND AND HAIL. GUSTY WINDS MAY ALSO BE NOTED WITH A FEW STORMS OVER
SOUTHEAST ARIZONA AND SOUTHWEST NEW MEXICO.
..UPPER GREAT LAKES/MIDWEST
UPPER TROUGH, CURRENTLY LOCATED ALONG THE DAKOTAS/MN BORDER, IS
FORECAST TO ADVANCE INTO THE UPPER GREAT LAKES BY LATE AFTERNOON.
MODEST MID-LEVEL HEIGHT FALLS WILL OVERSPREAD WI/MI AS A WEAK
SURFACE FRONT SETTLES ACROSS THE U.P. OF MI/WI BY PEAK HEATING.
WHILE BUOYANCY IS NOT FORECAST TO BE THAT STRONG, DEEP-LAYER SHEAR
WILL INCREASE SUCH THAT STORMS THAT EVOLVE ALONG THE BOUNDARY DURING
THE AFTERNOON WILL BE ADEQUATELY SHEARED FOR AT LEAST THE POTENTIAL
FOR ORGANIZED UPDRAFTS. SOME SUPERCELL POTENTIAL EXISTS BUT THE MAIN
RISKS APPEAR TO BE GUSTY WINDS AND HAIL.
FARTHER SOUTHEAST, LATEST WATER-VAPOR IMAGERY DEPICTS A PLUME OF
HIGHER PW EXTENDING ACROSS THE SOUTHERN PLAINS-MO-SOUTHERN LAKE MI.
A FEW WEAK EMBEDDED DISTURBANCES ARE NOTED ALONG THIS CORRIDOR WHICH
WILL LIFT NORTHEAST TOWARD LOWER MI. SCATTERED THUNDERSTORMS SHOULD
DEVELOP ALONG THIS CORRIDOR BY EARLY AFTERNOON AS THE BOUNDARY LAYER
WARMS WITHIN A WEAKLY CAPPED ENVIRONMENT. ALTHOUGH DEEP-LAYER FLOW
IS NOT PARTICULARLY STRONG, GUSTY WINDS COULD ACCOMPANY ROBUST
CONVECTION.
..SOUTHEAST AZ/SOUTHWEST NM
STRONG BOUNDARY-LAYER HEATING NEAR THE INTERNATIONAL BORDER INTO
NORTHERN MEXICO SHOULD ENCOURAGE DIURNALLY DRIVEN CONVECTION OVER
THE HIGHER TERRAIN LATER THIS AFTERNOON. STORMS SHOULD BE MORE
NUMEROUS SOUTH OF THE BORDER, BUT ISOLATED ACTIVITY IS EXPECTED TO
EVOLVE OVER SOUTHEAST AZ/SOUTHWEST NM AND DRIFT SLOWLY WITHIN A WEAK
FLOW REGIME. WHILE PWS ARE NOT PARTICULARLY HIGH FOR THIS TIME OF
YEAR, GUSTY WINDS COULD BE NOTED WITH THE MOST ROBUST CONVECTION.
..DARROW/MOORE.. 08/12/2025
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