165  
ACUS02 KWNS 111706  
SWODY2  
SPC AC 111705  
 
DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
ISSUED BY 15TH OWS SCOTT AIR FORCE BASE IL  
1205 PM CDT THU SEP 11 2025  
 
VALID 121200Z - 131200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS  
OF THE NORTHERN PLAINS AND THE FOUR CORNERS....  
   
..SUMMARY
 
 
STRONG TO SEVERE STORMS CAPABLE OF ISOLATED SEVERE WIND GUSTS ARE  
POSSIBLE ACROSS THE FOUR CORNERS REGION ON FRIDAY. ADDITIONAL STORMS  
ARE POSSIBLE OVER THE NORTHERN PLAINS AND UPPER MIDWEST FRIDAY.  
   
..NORTHERN PLAINS AND UPPER MIDWEST
 
 
A SHORTWAVE TROUGH AND ENHANCED SOUTHWESTERLY FLOW WILL MOVE OUT OF  
THE NORTHERN ROCKIES AND INTO THE NORTHERN PLAINS FRIDAY AS UPPER  
RIDGING BEGINS TO MOVE EASTWARD. ASSOCIATED WITH THE APPROACHING  
TROUGH, A WEAK LEE CYCLONE ALONG A STALLED FRONT OVER THE DAKOTAS  
WILL DRAW RICH LOW-LEVEL MOISTURE WESTWARD TOWARD A SECOND WEAK COLD  
FRONT MOVING OUT OF THE ROCKIES. MODEST ASCENT IS EXPECTED MUCH OF  
THE DAY ALONG AND NORTH OF THE SURFACE LOW/FRONT ACROSS NORTHERN WY,  
WESTERN ND AND CENTRAL/EASTERN MT. WHILE CLOUD COVER AND EARLY  
MORNING CONVECTION MAY TEMPER HEATING SOMEWHAT, ELEVATED BUOYANCY IS  
EXPECTED TO SUPPORT SCATTERED TO NUMEROUS STORMS THROUGH THE  
AFTERNOON. WITH 35-45 KT OF SOUTHWESTERLY FLOW ALOFT EXTENDING MID  
AND UPPER-LEVEL HODOGRAPHS, A FEW ELEVATED CLUSTERS OR SUPERCELLS  
ARE POSSIBLE. STEEP MID-LEVEL LAPSE RATES AND FAVORABLE DEEP-LAYER  
SHEAR COULD SUPPORT ISOLATED HAIL AND STRONG GUSTS WITH THE  
STRONGEST STORMS, THOUGH CONFIDENCE IN THE OVERALL SEVERE RISK  
REMAINS FAIRLY LOW GIVEN THE POTENTIAL FOR CLOUDS AND EARLY MORNING  
STORMS.  
 
CONVECTIVE COVERAGE MAY INCREASE THROUGH THE EVENING AND OVERNIGHT  
HOURS AS A 35-45 KT SOUTHERLY LOW-LEVEL JET DEVELOPS OVER THE  
PLAINS. CAM GUIDANCE REMAINS QUITE DISPERSIVE, BUT SOME SOLUTIONS  
SHOW THE POTENTIAL FOR ISOLATED SEVERE GUSTS WITH ELEVATED STORM  
CLUSTERS MOVING EASTWARD ACROSS THE DAKOTAS OVERNIGHT.  
 
A SECOND CLUSTER OF ELEVATED STORMS MAY BE ONGOING AT THE BEGINNING  
OF THE PERIOD ACROSS THE EASTERN DAKOTAS/WESTERN MN ASSOCIATED WITH  
A WEAK SHORTWAVE TROUGH AND LOW-LEVEL WARM ADVECTION ALONG THE  
STALLED FRONT. IF THIS OCCURS, A LOW-END WIND/HAIL THREAT COULD  
EXIST DURING THE MORNING AS THE SHORTWAVE CONTINUES  
EAST/SOUTHEASTWARD TOWARD THE GREAT LAKES. BUOYANCY AND ASCENT  
SHOULD DECREASE QUICKLY WITH EASTWARD EXTENT SUGGESTING ONLY A  
LIMITED SEVERE RISK.  
   
..FOUR CORNERS
 
 
A SHORTWAVE TROUGH AND AN ASSOCIATED BELT OF STRONGER SOUTHWESTERLY  
FLOW ALOFT WILL BE PRESENT OVER PORTIONS OF THE EASTERN GREAT BASIN  
AND CENTRAL ROCKIES FRIDAY. AN ASSOCIATED COLD FRONT WILL ALSO SHIFT  
EASTWARD, IMPINGING UPON A MODIFIED MONSOON AIR MASS ACROSS NORTHERN  
AZ/NM INTO EASTERN UT AND WESTERN/CENTRAL CO. A BAND OF SHOWERS AND  
POSSIBLY A FEW THUNDERSTORMS ARE LIKELY BE ONGOING EARLY IN THE  
PERIOD AHEAD OF THE FRONT. WHILE MOISTURE CONTENT (PWATS 0.5-0.8  
INCHES) WILL NOT BE OVERLY ROBUST, IT SHOULD BE SUFFICIENT TO  
SUPPORT WEAK DIURNAL DESTABILIZATION AMID CLOUD COVER AND REMNANT  
SHOWERS/STORMS. CONVECTION SHOULD GRADUALLY INCREASE IN COVERAGE  
ALONG THE FRONT AND ACROSS THE HIGHER TERRAIN BY LATE MORNING AND  
EARLY AFTERNOON. THE STRONGER MID-LEVEL FLOW COULD ALLOW FOR A FEW  
STORMS TO ORGANIZE INTO MUTLICELL CLUSTERS OR WEAK SUPERCELLS. WITH  
STEEP LOW AND MID-LEVEL LAPSE RATES PRESENT, STRONG GUSTS APPEAR  
POSSIBLE WITH ANY SUSTAINED STORMS, ALONG WITH SMALL HAIL.  
 
..15_OWS.. 09/11/2025  
 

 
 
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