668  
ACUS01 KWNS 221637  
SWODY1  
SPC AC 221636  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1136 AM CDT SUN JUN 22 2025  
 
VALID 221630Z - 231200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE UPPER  
MIDWEST TO THE CENTRAL/SOUTHERN HIGH PLAINS AND OVER PORTIONS OF THE  
NORTHEAST...  
   
..SUMMARY
 
 
ISOLATED TO SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP TODAY  
ACROSS THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY, SOME OF  
WHICH COULD PRODUCE LARGE HAIL, DAMAGING WIND GUSTS AND TORNADOES.  
STORMS ASSOCIATED WITH SEVERE GUSTS AND HAIL MAY ALSO DEVELOP ACROSS  
PARTS OF THE NORTHEAST, AND IN THE SOUTHERN AND CENTRAL PLAINS.  
   
..NORTHERN/CENTRAL PLAINS INTO THE UPPER MIDWEST
 
 
A WARM FRONT EXTENDS NORTHEAST FROM A SURFACE LOW OVER NORTHERN SD  
ACROSS NORTHERN MN AND EAST ACROSS THE NORTHERN GREAT LAKES. THIS  
WARM FRONT SHOULD LIFT NORTH THROUGH THE DAY, WHILE A COLD FRONT  
EXTENDS SOUTHWEST OF THE SURFACE LOW INTO NORTHEAST CO.  
THUNDERSTORMS OVER EASTERN ND/NORTHWEST MN HAVE PRODUCED NEAR SEVERE  
GUSTS AS THEY CONTINUE TO MOVE NORTHEAST TOWARDS THE INTERNATIONAL  
BORDER.  
 
REDEVELOPMENT OF THUNDERSTORMS IS ANTICIPATED TOWARDS LATE AFTERNOON  
OR EARLY EVENING ACROSS EASTERN ND/WESTERN MN SOUTHWARD INTO EASTERN  
SD AS A WEAK MID-LEVEL PERTURBATION LIFTS NORTHEAST ACROSS THE AREA,  
CONTRIBUTING LARGE-SCALE ASCENT AND WEAKENING THE CAPPING INVERSION.  
THESE STORMS WILL MOVE EAST/NORTHEAST WITHIN A STRONGLY UNSTABLE AIR  
MASS AND INCLUDE A MIX OF SUPERCELL AND CLUSTER MODES WITH A RISK  
FOR LARGE TO VERY LARGE HAIL INITIALLY, AND TRANSITION INTO AN  
INCREASING WIND THREAT WITH TIME. TORNADO POTENTIAL APPEARS TO BE  
GREATEST OVER NORTHERN MN, WHERE LOW-LEVEL SRH WILL BE MAXIMIZED.  
 
THE POTENTIAL FOR ELEVATED, POST-FRONTAL THUNDERSTORM DEVELOPMENT  
ACROSS THE NE PANHANDLE WILL EXIST LATER THIS AFTERNOON/EVENING,  
WITH STORMS MOVING EAST AND POSING A RISK INITIALLY FOR SEVERE HAIL.  
THE SEVERE WIND POTENTIAL WILL INCREASE WITH EASTWARD EXTENT AS  
STORMS CONGEAL AND TAP GREATER SURFACE INSTABILITY FARTHER EAST.  
   
..CENTRAL/SOUTHERN HIGH PLAINS
 
 
LOW-LEVEL MOISTURE ADVECTION AND RELATED AIRMASS DESTABILIZATION  
COUPLED WITH LOW-LEVEL CONVERGENCE ALONG THE LEE TROUGH IS EXPECTED  
TO RESULT IN THUNDERSTORM DEVELOPMENT FROM EASTERN CO/WESTERN KS  
THROUGH EASTERN NM AND INTO FAR WEST TX. VERTICAL SHEAR WILL BE  
MODEST, LIKELY RESULTING IN PREDOMINANTLY OUTFLOW-DOMINANT STORM  
STRUCTURES AND THE POTENTIAL FOR DAMAGING WIND GUSTS. SOME ISOLATED  
HAIL IS ALSO POSSIBLE WITH THE STRONGEST/MORE PERSISTENT UPDRAFTS.  
   
..NORTHEAST
 
 
OVERALL STORM INTENSITY ALONG THE WESTERN FLANK OF OUTFLOW FROM THE  
LONG-LIVED MCS REMAINS SUB SEVERE, AND HAVE NARROWED THE MARGINAL  
AND SLIGHT RISK AREAS TO ALONG AND IMMEDIATELY SOUTHWEST OF THE  
CONVECTIVE LINE. SUBSTANTIAL DIURNAL HEATING OF A VERY MOIST AIR  
MASS, AND 30-40 KTS OF EFFECTIVE SHEAR, MAY SUPPORT SOME SEVERE  
POTENTIAL AS STORMS MOVE GENERALLY SOUTHWARD ALONG THE EASTERN  
PERIPHERY OF THE MID-LEVEL RIDGE. ISOLATED TO WIDELY SCATTERED  
STRONG/SEVERE WIND GUSTS WILL BE POSSIBLE, IN ADDITION TO ISOLATED  
HAIL REPORTS GIVEN SEASONABLY STEEP MID-LEVEL LAPSE RATES.  
 
..BUNTING/SQUITIERI.. 06/22/2025  
 

 
 
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