191  
ACUS02 KWNS 120601  
SWODY2  
SPC AC 120600  
 
DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0100 AM CDT FRI SEP 12 2025  
 
VALID 131200Z - 141200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE  
SOUTHERN AND CENTRAL HIGH PLAINS AND THE NORTHERN PLAINS...  
   
..SUMMARY
 
 
STRONG TO SEVERE STORMS ARE POSSIBLE OVER PARTS OF THE SOUTHERN AND  
CENTRAL HIGH PLAINS AND NORTHERN PLAINS SATURDAY.  
   
..SYNOPSIS
 
 
THE WESTERN UPPER TROUGH WILL CONTINUE ITS SLOW PROGRESS EASTWARD ON  
SATURDAY. THE TROUGH IS EXPECTED TO EJECT INTO CENTRAL PLAINS BY  
EARLY SUNDAY MORNING. A FEW EMBEDDED SHORTWAVE TROUGHS WILL PIVOT  
INTO THE NORTHERN PLAINS AND STRONGER MID-LEVEL WINDS WILL EXTEND  
INTO THE SOUTHERN ROCKIES. AT THE SURFACE, A LOW IN THE NORTHERN  
PLAINS WILL BECOME MORE DIFFUSE DURING THE PERIOD.  
   
..SOUTHERN/CENTRAL HIGH PLAINS
 
 
ON THE SOUTHERN EDGE OF THE BROAD WESTERN TROUGH, STRONGER MID-LEVEL  
FLOW WILL BE PERPENDICULAR TO THE SOUTHERN ROCKIES INTO PART OF THE  
FRONT RANGE. LOW-LEVEL MOISTURE WILL ADVECT INTO THE REGIONS GIVEN  
SURFACE SOUTHEASTERLY WINDS. MOISTURE WILL BE GREATEST IN NEW MEXICO  
WITH MID/UPPER 50S F DEWPOINTS. FARTHER NORTH, FLOW WILL BECOME MUCH  
MORE MERIDIONAL AND MOISTURE WILL BE MORE LIMITED. WITHIN THE  
SOUTHERN ROCKIES, CLOUD COVER ASSOCIATED WITH THE TROUGH WILL  
GENERALLY KEEP LOW-LEVEL LAPSE RATES WEAK. HOWEVER, MODESTLY STEEP  
MID-LEVEL LAPSE RATES WITH THE COOLER AIR ALOFT AND 35-40 KTS OF  
EFFECTIVE SHEAR WILL PROMOTE SOME RISK FOR A FEW SUPERCELL  
STRUCTURES BY THE AFTERNOON. ISOLATED LARGE HAIL WILL BE THE MAIN  
RISK. WHILE A SIMILAR HAIL THREAT WILL BE PRESENT FOR MUCH OF THE  
FRONT RANGE, THIS AREA IS ALSO MORE LIKELY TO RECEIVE GREATER  
SURFACE HEATING. STEEPER LOW-LEVEL LAPSE RATES WILL SUPPORT A THREAT  
FOR ISOLATED SEVERE GUSTS WITH THE STRONGEST STORMS.  
   
..NORTHERN PLAINS
 
 
SCATTERED THUNDERSTORMS WILL LIKELY BE ONGOING AT THE START OF THE  
PERIOD. BY THIS TIME, STEEPER MID-LEVEL LAPSE RATES WILL LIKELY HAVE  
DIMINISHED FOR MUCH OF THE WESTERN DAKOTAS INTO EASTERN MONTANA AND  
WYOMING. THIS ACTIVITY WILL BE DRIVEN BY A NORTHWARD MOVING  
SHORTWAVE TROUGH AND LOW-LEVEL WARM ADVECTION. DESPITE CLOUD COVER  
COMPLICATING THE LOW-LEVEL THERMODYNAMIC ENVIRONMENT AND THE SURFACE  
LOW GRADUALLY WEAKENING WITH TIME, THERE MAY STILL BE ZONE OF  
GREATER POTENTIAL IN THE EASTERN DAKOTAS WHERE STEEPER MID-LEVEL  
LAPSE RATES WILL BE. GREATER SHEAR/FORCING WILL OVERLAP GREATER  
BUOYANCY DURING THE AFTERNOON IN THIS AREA AS WELL. THE STRONGEST  
STORMS, IF THEY DEVELOP, WILL LIKELY BE NEAR AND EAST OF THE  
MISSOURI RIVER. SMALL TO ISOLATED MARGINALLY SEVERE HAIL APPEARS TO  
BE THE PRIMARY HAZARD.  
   
..UPPER MIDWEST
 
 
A WEAK SHORTWAVE TROUGH IS EXPECTED TO MOVE THROUGH SOUTHERN  
WISCONSIN INTO THE SOUTHERN LAKE MICHIGAN VICINITY. THIS WILL  
PROMOTE A ZONE OF WARM ADVECTION THAT WILL ALLOW POTENTIALLY  
SCATTERED STORMS TO DEVELOP. WHILE SHEAR WILL BE MODESTLY ENHANCED  
WITH THE SHORTWAVE, GREATER BUOYANCY AND LAPSE RATES WILL BE  
DISPLACED TO THE WEST. A STRONGER STORM OR TWO COULD OCCUR, BUT  
LIMITED CONFIDENCE IN GREATER SEVERE STORM COVERAGE PRECLUDES  
PROBABILITIES.  
 
..WENDT.. 09/12/2025  
 

 
 
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