103  
ACUS02 KWNS 140508  
SWODY2  
SPC AC 140506  
 
DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1206 AM CDT SUN SEP 14 2025  
 
VALID 151200Z - 161200Z  
   
..NO SEVERE THUNDERSTORM AREAS FORECAST  
 
   
..SUMMARY  
 
ORGANIZED SEVERE THUNDERSTORM POTENTIAL APPEARS GENERALLY LOW ON  
MONDAY.  
   
..DISCUSSION  
 
A PAIR OF UPPER SHORTWAVE TROUGHS WILL BE LOCATED OVER THE NORTHERN  
ROCKIES AND THE UPPER MIDWEST ON MONDAY. THE UPPER TROUGH ORIENTED  
OVER THE EASTERN DAKOTAS/MN WILL LIFT NORTH INTO CANADA THROUGH  
EARLY EVENING, WHILE THE NORTHERN ROCKIES UPPER TROUGH MEANDERS  
SLOWLY EASTWARD, DEVELOPING AN UPPER CYCLONE OVER MT/WY. ANOTHER  
UPPER CYCLONE IS EXPECTED TO PERSIST OVER THE CAROLINAS, WHILE UPPER  
RIDING BUILDS ACROSS THE PACIFIC COAST STATES AND MIDWEST.  
 
AT THE SURFACE, SEASONAL BOUNDARY LAYER MOISTURE WILL BE IN PLACE  
ACROSS THE SOUTHERN AND CENTRAL PLAINS INTO THE MS VALLEY, RESULTING  
IN POCKETS OF WEAK TO MODERATE INSTABILITY. ANY STRONGER INSTABILITY  
IS LIKELY TO REMAIN DISPLACED FROM STRONGER VERTICAL SHEAR, WHICH  
WILL BE QUICKLY SHIFTING NORTHWARD FROM THE UPPER MIDWEST INTO  
CANADA WITH THE DEPARTING UPPER SHORTWAVE TROUGH. ISOLATED TO  
SCATTERED THUNDERSTORMS WILL STILL BE POSSIBLE WITHIN A CORRIDOR OF  
60S F DEWPOINTS AND MODERATE INSTABILITY FROM THE OZARKS VICINITY  
INTO MN WITHIN A LOW-LEVEL WARM ADVECTION REGIME. HOWEVER, SEVERE  
POTENTIAL WILL LARGELY REMAIN LOW GIVEN LIMITED SHEAR AND FORCING  
FOR ASCENT. THE EXCEPTION COULD BE A STRONG STORM OR TWO IN  
MN/WESTERN WI WHERE EFFECTIVE SHEAR MAGNITUDES AROUND 20-25 KT AND  
MLCAPE UP TO 2000 J/KG WILL BE IN PLACE. HOWEVER, GIVEN THE UPPER  
TROUGH WILL BE DEPARTING THE REGION, SUBSIDENCE MAY LIMIT STORM  
COVERAGE/LONGEVITY ACROSS THE AREA.  
 
ADDITIONAL SCATTERED STORMS ARE POSSIBLE ACROSS PARTS OF THE  
NORTHERN/CENTRAL HIGH PLAINS AHEAD OF A WEAK SURFACE FRONT/TROUGH.  
STEEP MIDLEVEL LAPSE RATES WILL BE IN PLACE, AND STRONG HEATING WILL  
AID IN STEEPENED LOW-LEVEL LAPSE RATES AMID A DEEPLY MIXED BOUNDARY  
LAYER. SEVERE POTENTIAL SHOULD REMAIN LIMITED GIVEN WEAK  
SHEAR/INSTABILITY, BUT INVERTED-V SUB-CLOUD THERMODYNAMIC PROFILES  
COULD FOSTER LOCALLY GUSTY WINDS WITH ANY SHOWERS/THUNDERSTORMS.  
 
..LEITMAN.. 09/14/2025  
 
 
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