938  
ACUS48 KWNS 180854  
SWOD48  
SPC AC 180852  
 
DAY 4-8 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0352 AM CDT MON AUG 18 2025  
 
VALID 211200Z - 261200Z  
   
..DISCUSSION
 
   
..THURSDAY/DAY 4 TO SATURDAY/DAY 6
 
 
ON THURSDAY, A SUBTLE SHORTWAVE TROUGH IS FORECAST TO MOVE EASTWARD  
ACROSS THE NORTHERN PLAINS. AN AXIS OF MODERATE INSTABILITY WILL  
LIKELY DEVELOP BY AFTERNOON AHEAD OF THE FRONT ACROSS THE EASTERN  
DAKOTAS AND NORTHWEST MINNESOTA. SCATTERED STORMS COULD DEVELOP  
DURING THE AFTERNOON NEAR THE INSTABILITY AXIS, WITH AN ISOLATED  
SEVERE THREAT POSSIBLE.  
 
ON FRIDAY, THE FRONT IS FORECAST TO MOVE SOUTHEASTWARD TOWARD THE  
UPPER MISSISSIPPI AND MID MISSOURI VALLEYS, AS AN AXIS OF  
INSTABILITY DEVELOPS DURING THE AFTERNOON. ISOLATED THUNDERSTORMS  
WILL BE POSSIBLE NEAR THE INSTABILITY AXIS, BUT THE SEVERE POTENTIAL  
IS EXPECTED TO REMAIN LOCALIZED, MOSTLY DUE TO MINIMAL CONVECTIVE  
COVERAGE.  
 
ON SATURDAY, THE FRONT IS FORECAST TO MOVE ACROSS THE GREAT LAKES  
REGION, EXTENDING WEST-SOUTHWESTWARD INTO THE CENTRAL U.S. ISOLATED  
STORMS WITH A POTENTIAL FOR LOCALIZED SEVERE WILL AGAIN BE POSSIBLE  
IN THE AFTERNOON AHEAD OF THE FRONT. DUE TO A LACK OF LARGE-SCALE  
ASCENT, CELL COVERAGE IS EXPECTED TO BE VERY ISOLATED.  
   
..SUNDAY/DAY 7 AND MONDAY/DAY 8
 
 
FROM SUNDAY INTO MONDAY, AN UPPER-LEVEL TROUGH AND AN ASSOCIATED  
COLD FRONT IS FORECAST TO MOVE ACROSS THE EASTERN U.S. THUNDERSTORM  
DEVELOPMENT WILL BE POSSIBLE AHEAD OF THE FRONT SUNDAY AFTERNOON IN  
THE CENTRAL APPALACHIANS, AND ALONG PARTS OF THE MIDDLE TO UPPER  
ATLANTIC SEABOARD ON MONDAY AFTERNOON. INSTABILITY AHEAD OF THE  
FRONT IS EXPECTED TO REMAIN WEAK IN MOST AREAS DURING THIS PERIOD,  
SUGGESTING ANY SEVERE THREAT WILL REMAIN LOCALIZED.  
 
..BROYLES.. 08/18/2025  
 
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