864  
ACUS48 KWNS 280901  
SWOD48  
SPC AC 280900  
 
DAY 4-8 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0400 AM CDT WED MAY 28 2025  
 
VALID 311200Z - 051200Z  
   
..DISCUSSION  
   
..SATURDAY/DAY 4 AND SUNDAY/DAY 5  
 
FROM SATURDAY INTO SUNDAY, A MID-LEVEL SHORTWAVE TROUGH IS FORECAST  
TO MOVE FROM THE CENTRAL PLAINS INTO THE SOUTHEAST. INSTABILITY IS  
NOT FORECAST BE PARTICULARLY STRONG HEAD OF THE TROUGH. HOWEVER,  
LARGE-SCALE ASCENT WILL SUPPORT SCATTERED THUNDERSTORM DEVELOPMENT  
ON SATURDAY IN PARTS OF THE CENTRAL PLAINS AND OZARKS, AND ON SUNDAY  
FROM EAST TEXAS INTO THE LOWER MISSISSIPPI VALLEY. DEEP-LAYER SHEAR  
SHOULD BE ADEQUATE FOR ISOLATED SEVERE THUNDERSTORM DEVELOPMENT. THE  
THREAT IS EXPECTED TO BE MARGINAL.  
   
..MONDAY/DAY 6 TO WEDNESDAY/DAY 8  
 
DURING THE EARLY WEEK PERIOD, A MID-LEVEL RIDGE IS FORECAST TO MOVE  
ACROSS THE CENTRAL U.S., AS A SHORTWAVE TROUGH MOVES THROUGH THE  
DESERT SOUTHWEST. AHEAD OF THIS FEATURE, LOW-LEVEL MOISTURE WILL  
INCREASE ACROSS THE GREAT PLAINS, AS LOW-LEVEL FLOW STRENGTHENS IN  
THE WAKE OF THE RIDGE. SURFACE DEWPOINTS ARE EXPECTED TO INCREASE  
INTO THE 60S F ACROSS MUCH OF THE GREAT PLAINS, WHICH SHOULD ALLOW  
FOR MODERATE TO STRONG DESTABILIZATION IN SOME AREAS DURING THE  
AFTERNOON. ALTHOUGH LARGE-SCALE ASCENT WILL GENERALLY BE WEAK ACROSS  
MOST OF THE GREAT PLAINS, THUNDERSTORM DEVELOPMENT WILL BE POSSIBLE  
MONDAY AFTERNOON OVER PARTS OF THE HIGH PLAINS. AN ISOLATED SEVERE  
THREAT COULD DEVELOP LATE MONDAY AFTERNOON INTO THE EVENING ALONG  
THE WESTERN EDGE OF THE STRONGER INSTABILITY FROM EASTERN NEW  
MEXICO, NORTHWARD INTO WESTERN SOUTH DAKOTA.  
 
DURING THE MID WEEK, THE SHORTWAVE TROUGH IS FORECAST TO MOVE ACROSS  
THE CENTRAL U.S. ON TUESDAY AND INTO THE GREAT LAKES ON WEDNESDAY.  
THUNDERSTORM DEVELOPMENT IS EXPECTED ACROSS AN UNSTABLE AIRMASS,  
WHICH IS FORECAST TO BE LOCATED IN THE GREAT PLAINS. FORECAST  
INSTABILITY AND DEEP-LAYER SHEAR SUGGEST A SEVERE THREAT WILL BE  
POSSIBLE IN AREAS THAT HAVE SUFFICIENT LARGE-SCALE FORCING, ALTHOUGH  
CONFIDENCE IS LOW CONCERNING ANY POTENTIAL SCENARIO. IF MODEL RUNS  
MAINTAIN CONSISTENCY AND SHOW MORE AGREEMENT AMONG SOLUTIONS OVER  
THE NEXT COUPLE OF RUNS, A 15 PERCENT AREA MAY BE NEEDED IN PARTS OF  
THE GREAT PLAINS DURING THE EARLY TO MID WEEK.  
 
..BROYLES.. 05/28/2025  
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