298  
ACUS02 KWNS 160546  
SWODY2  
SPC AC 160545  
 
DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1245 AM CDT SAT AUG 16 2025  
 
VALID 171200Z - 181200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF  
THE NORTHERN PLAINS EAST-SOUTHEASTWARD INTO THE SOUTHERN GREAT LAKES  
AND OHIO VALLEY...  
   
..SUMMARY
 
 
THUNDERSTORMS WITH POTENTIAL FOR ISOLATED SEVERE WIND GUSTS AND HAIL  
WILL BE POSSIBLE ON SUNDAY ACROSS PARTS OF THE NORTHERN PLAINS  
EAST-SOUTHEASTWARD INTO THE UPPER MIDWEST, SOUTHERN GREAT LAKES AND  
OHIO VALLEY.  
   
..NORTHERN PLAINS/MID MISSOURI VALLEY
 
 
AT MID-LEVELS, WEST-SOUTHWESTERLY FLOW WILL REMAIN OVER THE NORTHERN  
PLAINS ON SUNDAY. AT THE SURFACE, UPSLOPE FLOW WILL GRADUALLY BECOME  
ESTABLISHED OVER MUCH OF THE WESTERN AND CENTRAL DAKOTAS, AS A LOW  
DEEPENS OVER EASTERN MONTANA. AN AXIS OF MODERATE INSTABILITY IS  
FORECAST TO DEVELOP BY AFTERNOON FROM SOUTHERN SOUTH DAKOTA  
NORTHWESTWARD INTO EASTERN MONTANA. LARGE-SCALE ASCENT WILL BE WEAK  
ALONG THIS CORRIDOR KEEPING CONVECTIVE COVERAGE ISOLATED. MID-LEVEL  
LAPSE RATES ARE FORECAST TO BE STEEP AND 0-6 KM SHEAR IS FORECAST TO  
BE MOSTLY IN THE 25 TO 35 KNOT RANGE. THIS MAY BE ENOUGH FOR AN  
ISOLATED THREAT FOR HAIL AND SEVERE WIND GUSTS IN THE LATE AFTERNOON  
AND EARLY EVENING.  
 
...UPPER MISSISSIPPI VALLEY/SOUTHERN GREAT LAKES/OHIO VALLEY.  
A MID-LEVEL RIDGE WILL REMAIN IN PLACE ACROSS THE UPPER MISSISSIPPI  
VALLEY ON SUNDAY. FROM NEAR THE RIDGE AXIS AND TO THE EAST, STRONG  
INSTABILITY IS FORECAST TO DEVELOP BY AFTERNOON FROM NORTHEAST IOWA  
INTO NORTHERN ILLINOIS AND NORTHERN INDIANA. LARGE-SCALE ASCENT WILL  
REMAIN LIMITED, WHICH WILL KEEP CONVECTIVE COVERAGE ISOLATED. IF A  
CELL OR TWO CAN INITIATE AND PERSIST, THE STRONG INSTABILITY COULD  
BE ENOUGH FOR A FEW MARGINALLY SEVERE GUSTS.  
 
TO THE WEST OF THE MID-LEVEL RIDGE AXIS ACROSS MINNESOTA, ISOLATED  
TO SCATTERED THUNDERSTORMS MAY DEVELOP DURING THE AFTERNOON DUE TO A  
SUBTLE SHORTWAVE TROUGH APPROACHING FROM THE SOUTHWEST. WHILE  
MODERATE DEEP-LAYER SHEAR IS FORECAST ACROSS MUCH OF MINNESOTA, THIS  
CONVECTION WILL LIKELY REMAIN WELL TO THE NORTH OF THE AXIS OF  
INSTABILITY. FOR THIS REASON, ANY THREAT FOR SEVERE WIND GUSTS AND  
HAIL SHOULD BE MARGINAL.  
 
..BROYLES.. 08/16/2025  
 

 
 
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