716  
ACUS48 KWNS 300901  
SWOD48  
SPC AC 300859  
 
DAY 4-8 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0359 AM CDT FRI MAY 30 2025  
 
VALID 021200Z - 071200Z  
   
..DISCUSSION
 
 
AS MENTIONED IN WPC'S EXTENDED FORECAST DISCUSSION, AN AMPLIFIED  
SPLIT-FLOW PATTERN ACROSS THE CONUS RENDERS BELOW-AVERAGE  
PREDICTABILITY THROUGH THE PERIOD. WILL MAINTAIN INHERITED  
SEVERE-WEATHER AREAS FOR D4-5, WITH MESOSCALE SEVERE POTENTIAL  
EVIDENT IN D6 AND BEYOND BUT WITH POOR SYNOPTIC PREDICTABILITY.  
   
..D4/MONDAY
 
 
A POSITIVE-TILT MID/UPPER TROUGH SHOULD SHIFT EAST AS AN EMBEDDED  
SHORTWAVE IMPULSE OVER THE NORTHERN ROCKIES TRACKS NEAR THE  
INTERNATIONAL BORDER OVER THE NORTHERN GREAT PLAINS. A  
NORTHEAST/SOUTHWEST-ORIENTED COLD FRONT SHOULD ACCELERATE SOUTHWARD  
INTO THE CENTRAL HIGH PLAINS WHILE A WEAK FRONTAL WAVE TEMPORARILY  
STALLS THE FRONT OVER THE RED RIVER VALLEY OF THE NORTH. THERE ARE  
PRONOUNCED SIGNALS FOR AFTERNOON TO EVENING CONVECTION ALONG THE  
FRONT. INITIALLY STEEP MID-LEVEL LAPSE RATES WILL BE SUPPORTIVE OF  
SCATTERED SEVERE POTENTIAL. BUT IT APPEARS THAT STRONGER MID-LEVEL  
FLOW MAY LAG TO THE COOL SIDE OF THE FRONT, WHICH MAY LIMIT A  
GREATER THREAT.  
   
..D5/TUESDAY
 
 
COMPLEX SEVERE POTENTIAL IS EXPECTED ACROSS THE CENTRAL STATES.  
LOW-AMPLITUDE SHORTWAVE IMPULSES SHOULD BE PROGRESSING ACROSS PARTS  
OF THE NORTHERN UPPER MIDWEST TO THE CENTRAL HIGH PLAINS ON TUESDAY  
MORNING. SOME GUIDANCE SUGGESTS EXTENSIVE OVERNIGHT CONVECTION MAY  
BE ONGOING WITHIN A FAVORABLY DIFFLUENT UPPER-FLOW REGIME,  
CHARACTERIZED BY A COUPLED SOUTHERN-STREAM LEFT-EXIT AND  
NORTHERN-STREAM RIGHT-ENTRANCE REGIME. THIS RENDERS SUBSTANTIAL  
UNCERTAINTY ON WHERE MORE ROBUST BOUNDARY-LAYER DESTABILIZATION  
SHOULD OCCUR. WARM MID-LEVEL TEMPERATURES IN THE SOUTHERN STREAM  
SHOULD YIELD MODEST MID-LEVEL LAPSE RATES, WHICH FURTHER LOWERS  
CONFIDENCE. NEVERTHELESS, A BROAD AND RICH MOIST SECTOR AND ADEQUATE  
DEEP-LAYER SHEAR, ALONG WITH WIDESPREAD CONVECTION DURING THE  
AFTERNOON/EVENING, INDICATE SCATTERED SEVERE STORMS REMAIN POSSIBLE.  
 
..GRAMS.. 05/30/2025  
 
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