285  
ACUS48 KWNS 210849  
SWOD48  
SPC AC 210847  
 
DAY 4-8 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0347 AM CDT THU MAY 21 2026  
 
VALID 241200Z - 291200Z  
   
..DISCUSSION
 
 
SEVERE POTENTIAL WILL REMAIN LOW THROUGH THE BEGINNING OF THE  
EXTENDED PERIOD. WEAK TROUGHING WILL CONTINUE ACROSS THE CENTRAL  
PLAINS D4/SUNDAY BEFORE HEIGHT RISES BEGIN ACROSS THE CENTRAL US  
WITH A HIGH AMPLITUDE RIDGE SETTLING IN FROM THE WEST D5/MONDAY.  
THIS PATTERN WILL REMAIN IN PLACE THROUGH EARLY NEXT WEEK. SLOW  
MOISTURE RETURN WILL BE ONGOING ACROSS MUCH OF THE PLAINS INTO THE  
MIDWEST WITH OCCASIONAL ROUNDS OF WIDESPREAD RAINFALL AND  
THUNDERSTORMS, BUT GENERALLY WEAK FLOW AND SUBSIDENCE WILL KEEP  
ORGANIZED STORM POTENTIAL LOW.  
 
BY THE MIDWEEK, A TROUGH IS PROGGED TO BEGIN DEEPENING ACROSS THE  
PACIFIC NORTHWEST. AS THE UPPER LOW SLOWLY SHIFTS EASTWARD, STRONGER  
FLOW WILL OVERSPREAD THE INTERMOUNTAIN WEST INTO THE NORTHERN  
ROCKIES, RESULTING IN STRENGTHENING LEE TROUGHING ACROSS THE  
CENTRAL/NORTHERN PLAINS D6/TUESDAY AND D7/WEDNESDAY. MOISTURE  
ADVECTION WILL SPREAD NORTHWARD AMID STRENGTHENING SOUTHERLY FLOW  
ACROSS THE CENTRAL/NORTHERN PLAINS. WHILE THERE ARE SOME DIFFERENCES  
IN THE PLACEMENT OF UPPER-LEVEL AND SURFACE FEATURES, IT IS POSSIBLE  
THAT SEVERE CHANCES WILL RETURN ACROSS PORTIONS OF NORTHERN HIGH  
PLAINS. FOR NOW, CONFIDENCE IN EXACT CORRIDORS REMAINS LOW GIVEN  
MODEL GUIDANCE DIFFERENCES.  
 
..THORNTON.. 05/21/2026  
 
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