690  
ACUS01 KWNS 220114  
SWODY1  
SPC AC 220112  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0812 PM CDT SUN JUN 21 2026  
 
VALID 220100Z - 221200Z  
 
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR SOUTHWEST  
KS INTO NORTH-CENTRAL OK...  
   
..SUMMARY  
 
TORNADOES (POSSIBLY STRONG) AND DAMAGING WINDS REMAIN POSSIBLE THIS  
EVENING INTO PARTS OF THE MISSISSIPPI AND OHIO VALLEYS. A SWATH OF  
SEVERE GUSTS (POSSIBLY GREATER THAN 75 MPH) APPEARS POSSIBLE LATER  
TONIGHT FROM SOUTHWEST KANSAS INTO CENTRAL OKLAHOMA.  
   
..MID MS VALLEY INTO THE OHIO VALLEY  
 
AN MCV MOVING ACROSS IN WILL EVENTUALLY ENCOUNTER WEAKER LOW-LEVEL  
MOISTURE AND INSTABILITY WITH EASTWARD EXTENT. HOWEVER, A LONG-LIVED  
STORM CLUSTER MAY CONTINUE EASTWARD TOWARD PARTS OF SOUTHWEST OH AND  
EASTERN KY, BEFORE A DEFINITIVE WEAKENING TREND OCCURS. DAMAGING  
WIND AND EMBEDDED TORNADOES WILL REMAIN POSSIBLE WITH THE PRIMARY  
STORM CLUSTER UNTIL WEAKENING OCCURS. SEMI-DISCRETE CELLS AND SMALL  
CLUSTERS TRAILING THE MCV WILL ALSO CONTINUE TO POSE A THREAT OF  
TORNADOES (POSSIBLY STRONG) AND DAMAGING WINDS THROUGH THE EVENING,  
WITHIN A MOIST AND FAVORABLY SHEARED ENVIRONMENT. SEE MCD 1237 FOR  
MORE INFORMATION.  
   
..CENTRAL HIGH PLAINS INTO OK AND SOUTHERN MO  
 
WIDELY SCATTERED STORM DEVELOPMENT IS UNDERWAY NEAR A SURFACE  
BOUNDARY DRAPED FROM NORTHWEST OK INTO SOUTHEAST KS/SOUTHWEST MO.  
WHILE LARGE-SCALE FORCING IS GENERALLY MODEST AT BEST, MLCAPE OF  
2500-4000 J/KG AND EFFECTIVE SHEAR OF 40+ KT ARE CONDITIONALLY QUITE  
FAVORABLE FOR ORGANIZED STORMS. A FEW SUPERCELLS MAY PERSIST ALONG  
THE FRONT THROUGH THE EVENING, WITH A THREAT OF LARGE TO VERY LARGE  
HAIL AND LOCALIZED SEVERE GUSTS. ALSO, WHILE LOW-LEVEL FLOW IS WEAK,  
VORTICITY AND BACKED SURFACE WINDS NEAR THE BOUNDARY COULD SUPPORT  
SOME TORNADO POTENTIAL, IF A ROBUST SUPERCELL CAN BECOME  
ESTABLISHED.  
 
FARTHER NORTHWEST, A SUPERCELL CLUSTER IS ONGOING ACROSS WESTERN KS  
THIS EVENING. THIS CLUSTER WILL CONTINUE TO POSE A THREAT OF LARGE  
TO VERY LARGE HAIL, SEVERE GUSTS, AND POSSIBLY A TORNADO THROUGH THE  
EVENING. SEE MCD 1239 FOR MORE INFORMATION REGARDING THE SHORT-TERM  
THREAT.  
 
SHORT-TERM GUIDANCE (NOTABLY THE HRRR AND RRFS) SUGGESTS THAT THIS  
CLUSTER WILL CONTINUE TO GROW UPSCALE, AND POTENTIALLY EVOLVE INTO  
AN MCS THAT WILL MOVE SOUTHEASTWARD ACROSS SOUTHWEST KS INTO  
NORTHWEST AND CENTRAL OK, WITH THREAT OF SEVERE GUSTS (POTENTIALLY  
ABOVE 75 MPH) THROUGH THE OVERNIGHT HOURS. THIS EVOLUTION APPEARS  
PLAUSIBLE, IF EVENING CONVECTION ACROSS NORTHWEST OK IS NOT TOO  
DISRUPTIVE TO THE ENVIRONMENT. GIVEN THE VERY FAVORABLE MIDLEVEL  
LAPSE RATES ON THE 00Z DDC AND OUN SOUNDINGS, RICH MOISTURE, AND  
STRONG INSTABILITY AND DEEP-LAYER SHEAR, A 30%/CIG1 WIND AREA WAS  
ADDED FROM SOUTHWEST KS INTO CENTRAL OK.  
 
..DEAN.. 06/22/2026  
 
 
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