474  
ACUS48 KWNS 010817  
SWOD48  
SPC AC 010816  
 
DAY 4-8 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0316 AM CDT MON SEP 01 2025  
 
VALID 041200Z - 091200Z  
   
..DISCUSSION  
 
A PRONOUNCED MID-LEVEL TROUGH WILL GRADUALLY ADVANCE EASTWARD ACROSS  
THE EASTERN U.S. THROUGH THE REMAINDER OF THE WEEK INTO THIS  
WEEKEND, WITH MULTIPLE EMBEDDED MID-LEVEL PERTURBATIONS EXPECTED TO  
PIVOT AROUND THE UPPER TROUGH. THE UPPER TROUGH AND ASSOCIATED  
IMPULSES WILL REINFORCE SURFACE HIGH PRESSURE AND COOLER AIR ACROSS  
MUCH OF THE U.S. BETWEEN THE MISSISSIPPI RIVER AND APPALACHIANS  
THROUGH THE EXTENDED FORECAST PERIOD. THE SURFACE COLD FRONT WILL  
ENCOUNTER SEASONABLY RICH LOW-LEVEL MOISTURE WHILE ENCROACHING ON  
THE EASTERN SEABOARD, PROMPTING THE DEVELOPMENT OF AT LEAST  
SCATTERED THUNDERSTORMS. AT THE MOMENT, THE BEST CHANCE FOR STRONG  
STORMS, PERHAPS ACCOMPANIED BY AN ISOLATED SEVERE THREAT, WILL BE  
ALONG THE CENTRAL AND NORTHERN APPALACHIANS INTO THE MID ATLANTIC  
WITHIN THE DAYS 4-6 (THURSDAY-SATURDAY) TIME FRAME.  
 
MEANWHILE, AS SURFACE HIGH PRESSURE BUILDS OVER THE OH/TN VALLEY  
REGIONS, AND THE INTERIOR WEST, SEASONAL MOISTURE RETURN IS EXPECTED  
ACROSS PARTS OF THE SOUTHERN PLAINS DUE TO SURFACE LEE TROUGHING.  
THE AFOREMENTIONED IMPULSES PIVOTING AROUND THE BROADER SCALE UPPER  
TROUGH MAY GRAZE THE SOUTHERN PLAINS, PERHAPS PROMOTING ENOUGH  
VERTICAL WIND SHEAR ATOP A MOIST LOW-LEVEL AIRMASS TO SUPPORT  
ISOLATED SEVERE THUNDERSTORMS DAYS 4-6 (THURSDAY-SATURDAY).  
 
..SQUITIERI.. 09/01/2025  
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