834  
ACUS01 KWNS 190553  
SWODY1  
SPC AC 190552  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1252 AM CDT THU JUN 19 2025  
 
VALID 191200Z - 201200Z  
 
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE  
MIDDLE ATLANTIC...  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE  
NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY...  
   
..SUMMARY
 
 
SEVERE THUNDERSTORMS ARE EXPECTED ACROSS MUCH OF THE MIDDLE ATLANTIC  
REGION, AND TO A LESSER EXTENT INTO THE CAROLINAS AND OVER PORTIONS  
OF NEW ENGLAND. SEVERE WIND GUSTS ARE THE PRIMARY CONCERN. ISOLATED  
HAIL AND WIND THREAT IS EXPECTED ACROSS THE NORTHERN PLAINS INTO  
MINNESOTA, PRIMARILY DURING THE EVENING/OVERNIGHT.  
   
..EASTERN U.S
 
 
SEASONALLY STRONG UPPER TROUGH IS CURRENTLY LOCATED OVER IL AND  
SHOULD ADVANCE INTO THE OH VALLEY BY 18Z AS STRONGER 500MB FLOW  
DEVELOPS ACROSS WESTERN PA/NY. WITH TIME, 50+KT FLOW SHOULD  
TRANSLATE INTO THE MIDDLE ATLANTIC, COINCIDENT/JUST AHEAD OF THE  
PRIMARY SYNOPTIC FRONT. LATEST MODEL GUIDANCE SUGGESTS MODEST 0-3KM  
LAPSE RATES WILL DEVELOP BY MID DAY AS THE BOUNDARY LAYER WARMS  
AHEAD OF THE WIND SHIFT, ESPECIALLY FROM THE CAROLINAS INTO UPSTATE  
NY. IN FACT, MUCH OF THE I-95 CORRIDOR OVER THE MIDDLE ATLANTIC WILL  
WARM QUICKLY THROUGH THE 80S TO NEAR 90F, EFFECTIVELY REMOVING ANY  
INHIBITION. AS A RESULT, CONVECTION SHOULD READILY DEVELOP WITHIN A  
VERY MOIST ENVIRONMENT (PWS 1.75-2 INCHES) CHARACTERIZED BY MLCAPE  
IN EXCESS OF 2000 J/KG. FORECAST SOUNDINGS EXHIBIT DEEP  
WEST-SOUTHWESTERLY FLOW WITH 0-6KM BULK SHEAR AROUND 30KT. THESE  
PROFILES FAVOR ORGANIZED LINE SEGMENTS AND CLUSTERS, AND SEVERE WIND  
GUSTS WILL LIKELY BE NOTED WITH THE MOST ROBUST ACTIVITY. CONVECTION  
SHOULD SPREAD OFF THE MIDDLE ATLANTIC COAST DURING THE EVENING  
HOURS.  
   
..NORTHERN PLAINS/UPPER MS VALLEY
 
 
LATEST WATER-VAPOR IMAGERY DEPICTS A SHORT-WAVE TROUGH OVER  
SOUTHEAST BC. THIS FEATURE WILL SUPPRESS HEIGHTS ACROSS SOUTHERN  
AB/SK EARLY IN THE PERIOD, AND A SECONDARY DISTURBANCE WILL EJECT  
ACROSS SOUTHERN SK DURING THE EVENING. THESE FEATURES ARE EXPECTED  
TO ENCOURAGE CONVECTIVE DEVELOPMENT ALONG THE COOL SIDE OF A  
BOUNDARY THAT WILL BE DRAPED FROM THE UPPER MS VALLEY-CENTRAL  
ND-SOUTHERN SK. LOW-LEVEL WARM ADVECTION SHOULD AID BOUTS OF  
ELEVATED CONVECTION, BUT THE PRIMARY CONCERN IS WITH THUNDERSTORMS  
THAT EVOLVE DURING THE EARLY EVENING. STORMS THAT FORM OVER  
SOUTHEASTERN SK AND SOUTHWESTERN MB WILL SPREAD SOUTHEAST TOWARD A  
REGION OF INCREASING LOW-LEVEL WARM ADVECTION. LLJ IS FORECAST TO  
INCREASE ACROSS EASTERN SD INTO SOUTHWEST MN DURING THE LATE  
EVENING. ELEVATED SUPERCELLS SHOULD DEVELOP AHEAD OF THE CANADIAN  
CONVECTION AS THE LLJ STRENGTHENS INTO THE UPPER RED RIVER VALLEY.  
AN MCS MAY ULTIMATELY EVOLVE OVER THE UPPER MS VALLEY LATE IN THE  
PERIOD AS THE LLJ SHIFTS INTO SOUTHEAST MN/SOUTHWESTERN WI. HAIL AND  
WIND ARE THE PRIMARY CONCERN WITH THIS ACTIVITY.  
 
..DARROW/WEINMAN.. 06/19/2025  
 

 
 
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