835
ACUS01 KWNS 201630
SWODY1
SPC AC 201628
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1128 AM CDT WED AUG 20 2025
VALID 201630Z - 211200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
TEXAS INTO THE LOWER MISSISSIPPI VALLEY/SOUTHEAST...AND THE NORTHERN
PLAINS...
..SUMMARY
SCATTERED THUNDERSTORMS FROM TEXAS ACROSS THE LOWER MISSISSIPPI
VALLEY AND SOUTHEAST MAY POSE A RISK FOR LOCALIZED DAMAGING WIND
GUSTS THIS AFTERNOON AND EVENING. ISOLATED SEVERE THUNDERSTORMS MAY
ALSO OCCUR ACROSS PARTS OF CENTRAL/EASTERN MONTANA AND NORTHERN
NORTH DAKOTA, MAINLY THIS EVENING AND OVERNIGHT.
..TEXAS INTO THE LOWER MISSISSIPPI VALLEY AND SOUTHEAST
A CONVECTIVELY REINFORCED FRONT/OUTFLOW BOUNDARY FROM
EARLIER/ONGOING CONVECTION SHOULD ONCE AGAIN PROVIDE A FOCUS FOR
RENEWED CONVECTIVE DEVELOPMENT THIS AFTERNOON FROM PARTS OF
WEST-CENTRAL TX EASTWARD INTO THE LOWER MS VALLEY AND SOUTHEAST.
MID-LEVEL FLOW AND RELATED DEEP-LAYER SHEAR ARE EXPECTED TO REMAIN
WEAK, WHICH SHOULD GENERALLY LIMIT THUNDERSTORM ORGANIZATION. STILL,
A MODERATELY TO STRONGLY UNSTABLE ENVIRONMENT WILL EXIST ALONG/SOUTH
OF THE FRONT WITH CONTINUED DAYTIME HEATING, WITH SCATTERED TO
NUMEROUS THUNDERSTORMS LIKELY. SIMILAR TO YESTERDAY, WET MICROBURSTS
FROM CONVECTIVE DOWNDRAFTS MAY PRODUCE ISOLATED DAMAGING WINDS AS
LOW-LEVEL LAPSE RATES BECOME STEEPENED. THESE THUNDERSTORMS SHOULD
WEAKEN THROUGH THE EVENING WITH THE LOSS OF DAYTIME HEATING.
..NORTHERN PLAINS
THE NORTHERN PLAINS WILL BE INFLUENCED BY LATE-DAY/OVERNIGHT
MID-LEVEL HEIGHT FALLS AS A SHORTWAVE TROUGH MOVES EASTWARD FROM THE
CANADIAN/NORTHERN ROCKIES, WITH A RELATED COLD FRONT MOVING ACROSS
CENTRAL/EASTERN MT INTO ND TONIGHT. A NARROW CORRIDOR OF MODERATE TO
STRONG INSTABILITY WILL LIKELY DEVELOP ALONG/AHEAD OF THE COLD
FRONT, AND NEAR A PRE-FRONTAL SURFACE TROUGH. BUT, WARM MID-LEVEL
TEMPERATURES AND A CAPPED AIRMASS WILL LIKELY EXIST ALONG/SOUTH OF
THE INTERNATIONAL BORDER, WHICH SHOULD INHIBIT ROBUST CONVECTIVE
DEVELOPMENT FOR MUCH OF THE DAY.
ONE EXCEPTION MAY BE IN THE POST-FRONTAL ENVIRONMENT ACROSS EASTERN
MT THIS EVENING/TONIGHT. THE ENVIRONMENT HERE SHOULD BE CONDUCIVE TO
ISOLATED SEVERE THUNDERSTORMS CAPABLE OF PRODUCING BOTH LARGE HAIL
AND SEVERE GUSTS. WHILE THE RISK FOR SEVERE THUNDERSTORMS APPEARS
MORE CONDITIONAL INTO ND WHERE STRONGER DESTABILIZATION IS EXPECTED,
ISOLATED CONVECTIVE DEVELOPMENT MAY STILL OCCUR ACROSS NORTHWESTERN
ND IN PROXIMITY TO THE SURFACE LOW/FRONT LATE THIS AFTERNOON, AND
PERHAPS MORE SO THIS EVENING/OVERNIGHT. SHOULD THIS OCCUR, FORECAST
SOUNDINGS INDICATE THE ENVIRONMENT WOULD SUPPORT ISOLATED SUPERCELL
DEVELOPMENT WITH A RELATED HAIL/WIND THREAT.
..GLEASON/WENDT.. 08/20/2025
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