058  
ACUS48 KWNS 170855  
SWOD48  
SPC AC 170854  
 
DAY 4-8 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0354 AM CDT SUN AUG 17 2025  
 
VALID 201200Z - 251200Z  
   
..DISCUSSION
 
   
..WEDNESDAY/DAY 4 TO FRIDAY/DAY 6
 
 
ON WEDNESDAY, A MID-LEVEL RIDGE WILL LIKELY BE IN PLACE ACROSS THE  
NORTHERN PLAINS. AT THE SURFACE, A FRONT IS FORECAST TO BE LOCATED  
OVER THE OZARKS AND LOWER OHIO VALLEY. MODERATE INSTABILITY IS  
EXPECTED TO DEVELOP TO THE SOUTH OF THE FRONT, AND OVER PARTS OF THE  
NORTH-CENTRAL STATES. IN AREAS WHERE STORMS ARE EXPECTED, DEEP-LAYER  
SHEAR SHOULD BE WEAK, SUGGESTING A SEVERE THREAT IS UNLIKELY.  
 
ON THURSDAY, A MID-LEVEL SHORTWAVE TROUGH AND AN ASSOCIATED COLD  
FRONT ARE FORECAST TO MOVE EASTWARD INTO THE NORTHERN PLAINS. AN  
AXIS OF MODERATE INSTABILITY IS FORECAST AHEAD OF THE FRONT. THIS  
COMBINED WITH MODERATE DEEP-LAYER SHEAR COULD BE ENOUGH FOR AN  
ISOLATED SEVERE THREAT DURING THE AFTERNOON AND EVENING, MAINLY OVER  
EASTERN NORTH DAKOTA AND NORTHWESTERN MINNESOTA.  
 
THE FRONT AND ITS ASSOCIATED SHORTWAVE TROUGH ARE FORECAST TO MOVE  
INTO THE UPPER MISSISSIPPI AND MID MISSOURI VALLEYS ON FRIDAY.  
MODERATE INSTABILITY APPEARS LIKELY TO DEVELOP AHEAD OF THE FRONT  
DURING THE AFTERNOON. ALONG AND NEAR THE INSTABILITY AXIS, THE  
GREATEST POTENTIAL FOR THUNDERSTORM DEVELOPMENT COULD OCCUR IN THE  
CENTRAL PLAINS WITHIN NORTHWEST MID-LEVEL FLOW. AN ISOLATED SEVERE  
THREAT WILL BE POSSIBLE DURING THE LATE AFTERNOON AND EARLY EVENING.  
   
..SATURDAY/DAY 7 AND SUNDAY/DAY 8
 
 
ON SATURDAY AND SUNDAY, AN UPPER-LEVEL TROUGH IS FORECAST TO REMAIN  
OVER THE GREAT LAKES REGION. AHEAD OF THE TROUGH, AN AXIS OF  
INSTABILITY IS FORECAST TO DEVELOP IN THE CENTRAL APPALACHIANS,  
WHERE ISOLATED TO SCATTERED THUNDERSTORMS WILL BE POSSIBLE EACH  
AFTERNOON. MODERATE DEEP-LAYER SHEAR COULD BE SUFFICIENT FOR AN  
ISOLATED WIND-DAMAGE THREAT, MAINLY IN THE LATE AFTERNOON AS  
LOW-LEVEL LAPSE RATES BECOME STEEP.  
 
..BROYLES.. 08/17/2025  
 
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