800  
ACUS01 KWNS 270555  
SWODY1  
SPC AC 270554  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1254 AM CDT WED MAY 27 2026  
 
VALID 271200Z - 281200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF  
THE MID-ATLANTIC...  
   
..SUMMARY
 
 
THUNDERSTORMS WITH SEVERE WIND GUSTS WILL BE POSSIBLE TODAY ACROSS  
PARTS OF THE MID-ATLANTIC AND OHIO VALLEY. ISOLATED WIND GUSTS AND  
HAIL WILL ALSO BE POSSIBLE IN THE WESTERN GREAT LAKES AND FROM THE  
SOUTHERN TEXAS PANHANDLE INTO WEST TEXAS AND FAR WESTERN OKLAHOMA.  
   
..MID-ATLANTIC/OHIO VALLEY
 
 
AN UPPER-LEVEL TROUGH WILL MOVE SOUTHEASTWARD TODAY ACROSS THE GREAT  
LAKES. FLOW AHEAD OF THE TROUGH WILL BE WESTERLY OVER THE OHIO  
VALLEY AND MID-ATLANTIC. AT THE SURFACE, A COLD FRONT WILL MOVE  
SOUTHWARD INTO THE OHIO VALLEY. SOUTH OF THE FRONT, DEWPOINTS IN THE  
60S F WILL CONTRIBUTE TO POCKETS OF MODERATE INSTABILITY BY  
AFTERNOON. AS LOW-LEVEL CONVERGENCE AND INSTABILITY MAXIMIZES NEAR  
THE FRONT, THUNDERSTORMS ARE EXPECTED TO FORM AND MOVE  
EAST-SOUTHEASTWARD ACROSS THE OHIO VALLEY AND MID-ATLANTIC.  
 
RAP FORECAST SOUNDINGS JUST AHEAD OF THE FRONT IN NORTHERN VIRGINIA  
AT 21Z HAVE MLCAPE NEAR 1200 J/KG WITH 0-6 KM SHEAR AROUND 40 KNOTS.  
THIS WILL SUPPORT ORGANIZED THUNDERSTORMS, POTENTIALLY IN THE FORM  
OF MULTIPLE SHORT SEVERE LINE SEGMENTS. DURING THE MID TO LATE  
AFTERNOON, LOW-LEVEL LAPSE RATES ARE FORECAST TO PEAK NEAR 7.5 C/KM,  
WHICH WILL BE FAVORABLE FOR A WIND-DAMAGE THREAT. HAIL WILL ALSO BE  
POSSIBLE WITHIN THE STRONGER CORES.  
   
..WESTERN GREAT LAKES
 
 
NORTHWESTERLY MID-LEVEL FLOW WILL BE IN PLACE ACROSS THE WESTERN  
GREAT LAKES TODAY, AS A SHORTWAVE TROUGH MOVES SOUTHEASTWARD ACROSS  
THE REGION. AT THE SURFACE, A POCKET OF MAXIMIZED LOW-LEVEL MOISTURE  
WILL BE LOCATED OVER WISCONSIN, WHERE MLCAPE IS EXPECTED TO PEAK IN  
THE 1500 TO 2500 J/KG RANGE. THUNDERSTORMS THAT FORM DURING THE  
AFTERNOON THAT HAVE ACCESS TO MODERATE INSTABILITY AND STEEP  
LOW-LEVEL LAPSE RATES COULD HAVE POTENTIAL FOR ISOLATED WIND GUSTS.  
HAIL COULD ALSO OCCUR.  
   
..SOUTHERN TEXAS PANHANDLE/WEST TEXAS/FAR WESTERN OKLAHOMA
 
 
AT LOW-LEVELS, A MOIST AND UNSTABLE AIRMASS IS FORECAST TO ADVECT  
NORTHWARD ACROSS WEST TEXAS INTO THE SOUTHERN TEXAS PANHANDLE TODAY.  
A ZONE OF LOW-LEVEL CONVERGENCE WILL LIKELY DEVELOP OVER THE  
SOUTHERN TEXAS PANHANDLE, WITH UPSLOPE FLOW TO THE NORTH OF THIS  
FEATURE. AS SURFACE TEMPERATURES WARM DURING THE DAY, SCATTERED  
THUNDERSTORM DEVELOPMENT IS EXPECTED NEAR THE CONVERGENCE ZONE. RAP  
FORECAST SOUNDINGS TO THE SOUTH AND EAST OF AMARILLO AT 21Z HAVE  
STEEP LOW TO MID-LEVEL LAPSE RATES WITH LARGE SURFACE  
TEMPERATURE-DEWPOINT SPREADS. THIS MAY BE ENOUGH FOR ISOLATED SEVERE  
WIND GUSTS AND HAIL.  
 
..BROYLES/CHALMERS.. 05/27/2026  
 

 
 
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