416  
ACUS01 KWNS 251241  
SWODY1  
SPC AC 251239  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0739 AM CDT WED JUN 25 2025  
 
VALID 251300Z - 261200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF  
THE CAROLINAS...SOUTHEAST...AND MID MISSOURI VALLEY...  
   
..SUMMARY
 
 
SEVERE WIND GUSTS ARE POSSIBLE FROM PARTS OF THE CAROLINAS INTO THE  
SOUTHEAST, WITH WIDELY SCATTERED STRONG TO SEVERE STORMS POSSIBLE  
FROM THE NORTHERN HIGH PLAINS EASTWARD TO THE MID ATLANTIC.  
   
..SYNOPSIS
 
 
A LARGE UPPER RIDGE REMAINS IN PLACE OVER MUCH OF THE EASTERN CONUS  
THIS MORNING, ALTHOUGH AN UPPER LOW CENTERED NORTHEAST OF THE  
BAHAMAS IS BEGINNING TO IMPINGE ON ITS SOUTHEASTERN PERIPHERY.  
EARLY-MORNING SATELLITE IMAGERY ALSO SHOWS A WELL-DEFINED SHORTWAVE  
TROUGH MOVING THROUGH SOUTHERN CA AND SOUTHERN GREAT BASIN.  
 
RECENT SURFACE ANALYSIS REVEALS A LARGE RESERVOIR OF LOW-LEVEL  
MOISTURE BENEATH THIS UPPER RIDGE, WITH LOW 70S DEWPOINTS OVER MUCH  
OF THE OH AND TN VALLEYS, MID-ATLANTIC, AND SOUTHEAST. THIS  
LOW-LEVEL MOISTURE EXTENDS ACROSS MUCH OF THE PLAINS AS WELL, WITH  
MID 60S DEWPOINTS REACHING INTO SOUTH-CENTRAL/SOUTHEAST SD. A  
DIFFUSE, SOMEWHAT WAVY STATIONARY BOUNDARY EXISTS BETWEEN THIS MOIST  
AIRMASS AND THE DRIER, MORE CONTINENTAL AIRMASS EDGING INTO THE  
NORTHERN PLAINS, UPPER MIDWEST, AND GREAT LAKES.  
 
THIS LARGE AREA OF AMPLE LOW-LEVEL MOISTURE WILL SUPPORT POTENTIAL  
THUNDERSTORMS MUCH OF THE CONUS EAST OF THE ROCKIES. HIGHEST  
COVERAGE OF STRONG TO SEVERE STORMS IS ANTICIPATED ACROSS THE MID MO  
VALLEY AND THE SOUTHEAST/MID-ATLANTIC, WITH MORE WIDELY SCATTERED  
STRONG TO SEVERE STORMS ACROSS THE NORTHERN AND CENTRAL HIGH PLAINS  
AND ALONG THE FRONTAL ZONE ACROSS THE NORTHERN OH VALLEY.  
   
..MID-ATLANTIC/SOUTHEAST
 
 
IN ADDITION TO THE MOIST AIRMASS DESCRIBED IN THE SYNOPSIS, A POCKET  
OF SEASONALLY COLD MID-LEVEL TEMPERATURES (I.E. AROUND -10 DEG C AT  
500 MB) ASSOCIATED WITH THE BAHAMAS UPPER LOW EXTENDS INTO THE  
REGION. 12Z MHX AND CHS SOUNDINGS SAMPLED -10 AND -12 DEG C AT 500  
MB, AND 700-500 MB LAPSE RATES OF 7.9 AND 8.4 DEG C PER KM,  
RESPECTIVELY. THESE THERMODYNAMIC CONDITIONS WILL RESULT IN VERY  
STRONG BUOYANCY AS THE AIRMASS DIURNALLY HEATS THIS AFTERNOON.  
MLCAPE OVER 3000 J/KG IS ANTICIPATED FROM AL EASTWARD INTO THE  
CAROLINAS. THUNDERSTORM DEVELOPMENT IS EXPECTED ONCE CONVECTIVE  
INHIBITION ERODES AROUND 18Z, WITH THE VERY STRONG BUOYANCY  
SUPPORTING INTENSE UPDRAFTS. VERTICAL SHEAR WILL BE WEAK, WITH  
ERRATIC STORM MOTIONS AND A MULTICELLULAR, PULSE MODE LIKELY. EVEN  
SO, STEEP LOW-LEVEL LAPSE RATES SHOULD SUPPORT STRONG DOWNDRAFTS AND  
NUMEROUS INSTANCES OF DAMAGING GUSTS ARE EXPECTED. THESE STORMS WILL  
LIKELY WANE WITH THE LOSS OF DAYTIME HEATING.  
   
..MID MO VALLEY INTO THE UPPER MS VALLEY
 
 
LOW-LEVEL MOISTURE ADVECTION ACROSS THE REGION TODAY WILL BRING LOW  
70S DEWPOINTS IN SOUTHERN MN BY THE LATE AFTERNOON, WHILE ALSO  
SHARPENING A WARM FRONTAL ZONE. BY 18Z THIS WARM FRONT IS FORECAST  
TO EXTEND FROM A LOW OVER THE CENTRAL NE/SD BORDER VICINITY TO NEAR  
THE MN/IA BORDER. CONVERGENCE ALONG THIS BOUNDARY, AS WELL AS ASCENT  
ATTENDANT TO A CONVECTIVELY GENERATED VORTICITY MAXIMUM ROUNDING THE  
UPPER RIDGE, IS EXPECTED TO PROMOTE THUNDERSTORM DEVELOPMENT WITHIN  
THE MODERATE BUOYANT AIRMASS IN PLACE. MODERATE SOUTHWESTERLY FLOW  
ALOFT IS ANTICIPATED OVER THE REGION AS WELL, WITH THE RESULTING  
COMBINATION OF BUOYANCY AND SHEAR SUPPORTING STRONG TO SEVERE  
STORMS. A FEW SUPERCELLS ARE POSSIBLE, BUT ONE OR MORE BOWING LINE  
SEGMENTS CAPABLE OF DAMAGING GUSTS ARE THE PRIMARY SEVERE THREAT.  
   
..NORTHERN/CENTRAL HIGH PLAINS
 
 
THE SHORTWAVE TROUGH THAT CURRENTLY EXTENDS FROM CENTRAL MT TROUGH  
EASTERN ID IS FORECAST TO CONTINUE EASTWARD TODAY. AHEAD OF THE  
TROUGH, A MOIST AND UNSTABLE AIRMASS WILL BE IN PLACE BY AFTERNOON  
FROM EASTERN COLORADO NORTHWESTWARD INTO EASTERN MONTANA. AS SURFACE  
TEMPERATURES WARM TODAY, SCATTERED CONVECTIVE INITIATION WILL TAKE  
PLACE IN THE HIGHER TERRAIN, WITH STORMS MOVING EAST-NORTHEASTWARD  
INTO THE LOWER ELEVATIONS DURING THE AFTERNOON. VERTICAL SHEAR WILL  
BE MODEST, WITH THE STRONGEST SHEAR ACROSS THE NORTHERN HIGH PLAINS,  
BUT HIGH CLOUD BASES AND STEEP LOW-LEVEL LAPSE RATES COULD STILL  
SUPPORT DAMAGING WIND GUSTS ALONG SURGING COLD POOLS. ISOLATED HAIL  
IS POSSIBLE ACROSS THE HIGHER TERRAIN AS WELL.  
 
..MOSIER/WENDT.. 06/25/2025  
 

 
 
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