602  
ACUS48 KWNS 130853  
SWOD48  
SPC AC 130851  
 
DAY 4-8 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0351 AM CDT SUN APR 13 2025  
 
VALID 161200Z - 211200Z  
   
..DISCUSSION  
 
AN ACTIVE SEVERE WEATHER PATTERN IS EXPECTED LATE WEEK INTO NEXT  
WEEKEND.  
   
..D5/THURSDAY  
 
GUIDANCE HAS CONVERGED TO A SIGNAL OF SEVERE-STORM THREAT CENTERED  
ON THURSDAY EVENING AS A DEEP SURFACE CYCLONE BECOMES ESTABLISHED IN  
THE KS VICINITY, DOWNSTREAM OF A LONGWAVE TROUGH IN THE WEST. AN  
ENRICHING LOW-LEVEL MOISTURE PLUME WILL BE ADVECTED NEARLY DUE NORTH  
FROM THE WESTERN GULF TOWARDS THE LOWER MO VALLEY. A STOUT EML  
SHOULD LIMIT CONVECTIVE DEVELOPMENT ALONG MUCH OF THE DRYLINE. BUT A  
STRENGTHENING LOW-LEVEL JET SHOULD SUPPORT THUNDERSTORM DEVELOPMENT  
TO THE NORTHEAST OF THE SURFACE LOW AMID STRONG DEEP-LAYER SHEAR.  
   
..D6/FRIDAY  
 
A RATHER BROAD SWATH OF 50+ KT 500-MB SOUTHWESTERLIES APPEARS LIKELY  
TO BECOME ESTABLISHED FROM THE SOUTHERN HIGH PLAINS TO THE GREAT  
LAKES, DOWNSTREAM OF A BROAD TROUGH IN THE SOUTHWEST AND A SEPARATE  
NORTHERN-STREAM WAVE AROUND NORTHERN ON. WHILE THE DEEP CYCLONE OVER  
THE KS VICINITY WILL WEAKEN, IT SHOULD TRACK TOWARDS THE CENTRAL  
GREAT LAKES IN RESPONSE TO THE NORTHERN WAVE. ALONG ITS TRAILING  
COLD FRONT, EXTENSIVE THUNDERSTORM DEVELOPMENT IS ANTICIPATED FRIDAY  
AFTERNOON/EVENING. GIVEN THE AFOREMENTIONED STRONG MID-LEVEL FLOW  
REGIME, A BROAD CORRIDOR OF SEVERE THREAT IS WARRANTED.  
   
..D7-8/SATURDAY-SUNDAY  
 
PREDICTABILITY FOR A 15 PERCENT HIGHLIGHT WANES SOMEWHAT NEXT  
WEEKEND, BUT AREAS WILL PROBABLY BE NEEDED IN LATER OUTLOOKS.  
SATURDAY MAY CONSIST OF CONFINED, BIMODAL THREAT AREAS ACROSS THE  
LOWER MID-ATLANTIC STATES AND SOUTHERN HIGH/GREAT PLAINS. FOR THE  
FORMER, THE DEGREE OF INSTABILITY AND POSITION OF A SOUTHEAST-MOVING  
COLD FRONT ON THE PERIPHERY OF A FAST ZONAL FLOW REGIME ARE THE MAIN  
UNCERTAINTY DRIVERS. FOR THE LATTER, TIMING OF THE PIVOT AND  
EASTWARD EJECTION OF THE LOWER CO VALLEY SHORTWAVE IMPULSE INTO THE  
SOUTH-CENTRAL STATES WILL BE CRITICAL. BASED ON LATEST GUIDANCE, IT  
APPEARS SUNDAY COULD HAVE A BROADER CORRIDOR OF SEVERE POTENTIAL.  
 
..GRAMS.. 04/13/2025  
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