410  
ACUS01 KWNS 110542  
SWODY1  
SPC AC 110541  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1241 AM CDT MON AUG 11 2025  
 
VALID 111200Z - 121200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF  
THE SOUTHERN HIGH PLAINS AND RED RIVER VALLEY OF THE NORTH...  
   
..SUMMARY  
 
STRONG THUNDERSTORMS ACCOMPANIED BY AT LEAST SOME RISK FOR SEVERE  
WIND AND HAIL MAY IMPACT PARTS OF EASTERN NEW MEXICO INTO THE TEXAS  
SOUTH PLAINS, AS WELL AS PARTS OF EASTERN NORTH DAKOTA INTO  
NORTHWESTERN MINNESOTA, LATE THIS AFTERNOON AND EVENING.  
   
..SYNOPSIS  
 
LATE-EVENING WATER-VAPOR IMAGERY DEPICTS AN UPPER TROUGH/VORTICITY  
MAXIMUM SETTLING INTO THE SOUTHERN/CENTRAL HIGH PLAINS. THIS FEATURE  
IS EXPECTED TO STALL AND WEAKEN OVER THE PLAINS OVER THE NEXT 24  
HOURS WITH A GRADUAL ABATEMENT OF MID-LEVEL FLOW. TO THE NORTH, A  
PRONOUNCED MID-LEVEL WAVE IS APPARENT OVER THE CANADIAN  
ROCKIES/PRAIRIES. THIS FEATURE WILL CONTINUE SOUTHEASTWARD INTO THE  
NORTHERN PLAINS AND UPPER MISSISSIPPI RIVER VALLEY THROUGH TONIGHT.  
STRONG/SEVERE THUNDERSTORM CHANCES WILL LARGELY BE ATTENDANT TO  
THESE MID-LEVEL FEATURES.  
   
..SOUTHERN HIGH PLAINS  
 
05Z SURFACE OBSERVATIONS ACROSS THE SOUTHERN PLAINS REVEAL A  
COMPOSITE FRONTAL ZONE/OUTFLOW BOUNDARY DRAPED FROM FAR NORTHEAST NM  
THROUGH THE TX/OK PANHANDLES AND ROUGHLY ALONG THE OK/KS BORDER.  
THIS BOUNDARY WILL LIKELY BE DISPLACED SOUTHWARD AS A RESULT OF  
EARLY-MORNING CONVECTION, THOUGH PRECISELY WHERE THIS BOUNDARY  
RESIDES BY PEAK HEATING IS SOMEWHAT UNCERTAIN. REGARDLESS,  
THUNDERSTORM DEVELOPMENT ALONG THIS BOUNDARY IS EXPECTED BY LATE  
AFTERNOON/EARLY EVENING. TO THE SOUTH OF THIS BOUNDARY, EASTERLY  
WINDS ON THE NORTHERN PERIPHERY OF A WEAK SURFACE LOW OVER THE  
PERMIAN BASIN WILL MAINTAIN AN UPSLOPE FLOW REGIME ALONG THE EASTERN  
SLOPES OF THE SACRAMENTO, SANDIA MANZANO, AND SANGRE DE CRISTO  
MOUNTAINS. MODEST WESTERLY MID-LEVEL FLOW ATOP EASTERLY LOW-LEVEL  
WINDS SHOULD YIELD SUFFICIENT DEEP-LAYER SHEAR FOR A FEW ORGANIZED  
STORMS, INCLUDING A SUPERCELL OR TWO. WITH TIME, UPSCALE GROWTH  
AND/OR MERGING WITH ADDITIONAL CONVECTION DEVELOPING ALONG THE  
SURFACE BOUNDARY WILL PROMOTE AN INCREASED THREAT FOR SEVERE GUSTS  
THROUGH EARLY EVENING. WHILE CONVECTION IS EXPECTED NORTHEASTWARD  
ALONG MUCH OF THE BOUNDARY FROM CENTRAL OK INTO ADJACENT PORTIONS OF  
KS/MO, WEAKER MID-LEVEL WINDS WITH EASTWARD EXTENT CASTS DOUBT ON  
THE POTENTIAL FOR A ROBUST SEVERE THREAT (ASIDE FROM OCCASIONAL  
STRONG WET DOWNBURSTS).  
   
..RED RIVER VALLEY OF THE NORTH  
 
MODEST SURFACE CYCLOGENESIS IS ANTICIPATED ACROSS THE CENTRAL  
CANADIAN PRAIRIES OVER THE NEXT 24 HOURS AS THE MID-LEVEL WAVE  
APPROACHES THE INTERNATIONAL BORDER. AN ATTENDANT COLD FRONT IS  
FORECAST TO SPREAD ACROSS THE NORTHERN PLAINS THROUGH LATE AFTERNOON  
AND WILL IMPINGE ON A PLUME OF SEASONAL LOW-LEVEL MOISTURE. WHILE  
MID-LEVEL LAPSE RATES WILL REMAIN MODEST (AROUND 6-7 C/KM), ADEQUATE  
BUOYANCY SHOULD BE IN PLACE FOR DEEP CONVECTION. 30-40 KNOT  
MID-LEVEL FLOW SHOULD PROVIDE SUFFICIENT DEEP-LAYER SHEAR FOR  
ORGANIZED STORMS, THOUGH THE MARGINAL THERMODYNAMIC ENVIRONMENT WILL  
LIKELY BE A MODULATING FACTOR IN OVERALL STORM INTENSITY. STRONG  
FRONTAL FORCING SHOULD PROMOTE UPSCALE GROWTH THROUGH THE EVENING  
HOURS WITH AN ASSOCIATED THREAT FOR DAMAGING/SEVERE WINDS.  
 
..MOORE/DARROW.. 08/11/2025  
 
 
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