982  
ACUS01 KWNS 201248  
SWODY1  
SPC AC 201246  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0746 AM CDT SAT JUN 20 2026  
 
VALID 201300Z - 211200Z  
 
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF  
THE CENTRAL PLAINS...  
   
..SUMMARY
 
 
SEVERE THUNDERSTORMS ARE LIKELY ACROSS PARTS OF THE CENTRAL PLAINS  
MAINLY THIS AFTERNOON AND EVENING. LARGE TO VERY LARGE HAIL, SEVERE  
WINDS (SOME 75+ MPH), AND A FEW TORNADOES ARE POSSIBLE.  
   
..CENTRAL PLAINS
 
 
RECENT SURFACE OBSERVATIONS SHOW A FRONT EXTENDING FROM THE CENTRAL  
HIGH PLAINS OF EASTERN CO INTO KS, AND CONTINUING EAST-NORTHEASTWARD  
INTO THE MID MS VALLEY/UPPER MIDWEST. ISOLATED/ELEVATED  
THUNDERSTORMS ARE ONGOING THIS MORNING TO THE NORTH OF THE FRONT  
ACROSS PARTS OF CENTRAL NE INTO NORTH-CENTRAL KS, LIKELY AIDED BY  
WEAK LOW-LEVEL WARM ADVECTION OVER THE SOUTHERN/CENTRAL PLAINS.  
WHILE ISOLATED HAIL MAY OCCUR IN THE SHORT-TERM WITH THIS ACTIVITY  
GIVEN WEAK MUCAPE AND STRONG SHEAR IN THE CLOUD-BEARING LAYER,  
CURRENT EXPECTATIONS ARE FOR A MORE ROBUST SEVERE THREAT TO DEVELOP  
ACROSS THE CENTRAL PLAINS LATER THIS AFTERNOON AND EVENING.  
 
INITIALLY HIGH-BASED THUNDERSTORMS WILL LIKELY FORM BY EARLY TO MID  
AFTERNOON ALONG/EAST OF THE HIGHER TERRAIN OF EASTERN CO/SOUTHEAST  
WY IN A WEAK LOW-LEVEL UPSLOPE FLOW REGIME, AND AS MODEST  
LARGE-SCALE ASCENT PRECEDING AN EASTWARD-MOVING SHORTWAVE TROUGH  
OVERSPREADS THE CENTRAL ROCKIES/HIGH PLAINS. GREATER LOW-LEVEL  
MOISTURE (60S SURFACE DEWPOINTS) WILL BE IN PLACE WITH EASTWARD  
EXTENT ACROSS KS/NE, AND THESE THUNDERSTORMS SHOULD GRADUALLY  
STRENGTHEN AS THEY MOVE EASTWARD. DEEP-LAYER SHEAR APPEARS STRONG  
ENOUGH TO SUPPORT SUPERCELLS WITH AN ATTENDANT THREAT FOR LARGE  
HAIL, WITH STEEP MID-LEVEL LAPSE RATES AND AMPLE INSTABILITY IN THE  
HAIL-GROWTH ZONE POSSIBLY SUPPORTING ISOLATED VERY LARGE HAIL (2+  
INCHES).  
 
WHILE EXACT DETAILS OF SUBSEQUENT CONVECTIVE EVOLUTION REMAIN  
SOMEWHAT UNCLEAR, THESE INITIAL SUPERCELLS WILL PROBABLY TEND TO  
INTERACT/GROW UPSCALE IN SOME FORM ALONG AND NEAR THE SURFACE FRONT  
FROM LATE AFTERNOON THROUGH THE EVENING AS A SOUTHERLY LOW-LEVEL JET  
STRENGTHENS OVER THE CENTRAL HIGH PLAINS. AN INCREASING THREAT FOR  
AT LEAST SCATTERED SEVERE/DAMAGING WINDS SHOULD BE REALIZED AS ONE  
OR MORE BOWING CLUSTERS SPREADS EAST-SOUTHEASTWARD ACROSS NE/KS.  
ISOLATED SIGNIFICANT GUSTS (75+ MPH) MAY OCCUR WITH THE MORE INTENSE  
PORTIONS OF THESE CLUSTERS. SOME RISK FOR A FEW TORNADOES SHOULD  
ALSO EXIST, MAINLY LATE THIS AFTERNOON INTO THE EVENING WITH EITHER  
PERSISTENT SUPERCELLS OR EMBEDDED WITHIN CLUSTERS AS 0-1 KM SRH  
INCREASES IN TANDEM WITH THE LOW-LEVEL JET. A SEVERE WIND THREAT MAY  
CONTINUE THROUGH THE OVERNIGHT HOURS FARTHER EAST ACROSS KS AND  
PERHAPS INTO PARTS OF WESTERN MO.  
   
..NORTHERN UTAH/EASTERN IDAHO INTO WESTERN/CENTRAL WYOMING
 
 
A WEAK MID-LEVEL SHORTWAVE TROUGH OVER THE NORTHERN GREAT BASIN THIS  
MORNING WILL CONTINUE TO MOVE EASTWARD ACROSS THE NORTHERN/CENTRAL  
ROCKIES TODAY. ALTHOUGH LOW-LEVEL MOISTURE IS EXPECTED TO REMAIN  
LIMITED ALONG/WEST OF THE HIGHER TERRAIN, STEEPENED LOW/MID-LEVEL  
LAPSE RATES WILL EXIST WITH A VERY WELL-MIXED BOUNDARY LAYER THIS  
AFTERNOON. MODESTLY ENHANCED MID-LEVEL FLOW WILL SUPPORT  
EAST-NORTHEASTWARD DEVELOPING CONVECTION THROUGH THE  
AFTERNOON/EVENING ACROSS PARTS OF NORTHERN UT/EASTERN ID INTO  
WESTERN/CENTRAL WY. THIS ACTIVITY MAY POSE A THREAT FOR OCCASIONAL  
STRONG TO SEVERE WINDS, BUT THE OVERALL SEVERE THREAT SHOULD TEND TO  
REMAIN ISOLATED DUE TO THE WEAK INSTABILITY FORECAST.  
   
..GULF COAST/SOUTHEAST
 
 
MODEST FLOW ALOFT (GENERALLY 25 KT OR LESS) WILL EXIST TODAY ACROSS  
MUCH OF THE GULF COAST/SOUTHEAST, AS A MID-LEVEL ANTICYCLONE REMAINS  
ANCHORED OVER THE GULF. A VERY MOIST LOW-LEVEL AIRMASS, WITH SURFACE  
DEWPOINTS IN THE MID/UPPER 70S TO LOW 80S, EXISTS ALONG/SOUTH OF  
CONVECTION ONGOING FROM PARTS OF COASTAL/EAST TX INTO THE LOWER MS  
VALLEY. GIVEN THE WEAK MID-LEVEL FLOW AND RELATED DEEP-LAYER SHEAR,  
OVERALL THUNDERSTORM ORGANIZATION AND INTENSITY SHOULD REMAIN FAIRLY  
LIMITED. EVEN SO, OCCASIONAL DAMAGING WINDS COULD OCCUR AS THE  
LOOSELY ORGANIZED CLUSTER SPREADS EAST-SOUTHEASTWARD INTO A  
DESTABILIZING AIRMASS ACROSS THE LOWER MS VALLEY/CENTRAL GULF COAST  
STATES THROUGH THE AFTERNOON.  
   
..WESTERN PENNSYLVANIA
 
 
WITHIN WEST-NORTHWESTERLY MID-LEVEL FLOW, LOW-TOPPED THUNDERSTORMS  
SHOULD DEVELOP/MOVE ACROSS PARTS OF WESTERN PA AND VICINITY THIS  
AFTERNOON. INSTABILITY WILL REMAIN WEAK, BUT MODESTLY ENHANCED FLOW  
AND STEEP LOW-LEVEL LAPSE RATES MAY SUPPORT OCCASIONAL STRONG GUSTS  
FROM CONVECTIVE DOWNDRAFTS. THE OVERALL MAGNITUDE OF THE THREAT  
STILL APPEARS TOO LIMITED FOR LOW SEVERE WIND PROBABILITIES.  
 
..GLEASON/BROYLES.. 06/20/2026  
 

 
 
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