801  
AWUS01 KWNH 261912  
FFGMPD  
MDZ000-VAZ000-DCZ000-WVZ000-OHZ000-KYZ000-INZ000-270100-  
 
MESOSCALE PRECIPITATION DISCUSSION 0533  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
311 PM EDT FRI JUN 26 2026  
 
AREAS AFFECTED...PORTIONS OF THE OH VALLEY...CENTRAL APPALACHIANS  
AND MID-ATLANTIC  
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE  
 
VALID 261911Z - 270100Z  
 
SUMMARY...SCATTERED AREAS OF SHOWERS AND THUNDERSTORMS WILL POSE  
AT LEAST A LOCALIZED THREAT OF FLASH FLOODING THROUGH EARLY THIS  
EVENING GIVEN INCREASINGLY HIGH RAINFALL RATE POTENTIAL.  
 
DISCUSSION...THE MID-AFTERNOON GOES-E VISIBLE SATELLITE IMAGERY  
ALONG WITH RADAR DATA SHOWS SOME GRADUAL INCREASE IN THE COVERAGE  
OF MAINLY SCATTERED SHOWERS AND THUNDERSTORMS ACROSS PORTIONS OF  
THE OH VALLEY, CENTRAL APPALACHIANS AND THE INTERIOR OF THE  
CENTRAL MID-ATLANTIC. MLCAPE VALUES HAVE INCREASED TO 500 TO 1000  
J/KG, AND THE PWS ACROSS THE REGION ARE GRADUALLY INCREASING AS  
UPSTREAM MOISTURE TRANSPORT FROM THE MID-SOUTH FOCUSES ACROSS  
BROADER AREAS OF THE OH VALLEY AND EASTWARD INTO THE CENTRAL  
APPALACHIANS. PWS WEST OF THE APPALACHIANS HAVE RISEN TO 1.5 TO  
1.75 INCHES, WITH VALUES CLOSER TO 1.5 INCHES OVER THE CENTRAL  
MID-ATLANTIC.  
 
MULTIPLE UPSTREAM SHORTWAVE IMPULSES TRANSITING THE OH VALLEY WILL  
BEGIN TO MOVE INTO THE CENTRAL APPALACHIANS AND THE INTERIOR OF  
THE MID-ATLANTIC GOING THROUGH EARLY THIS EVENING. THERE MAY BE  
JUST ENOUGH UPTICK IN CONVECTIVE COVERAGE, AND THE RAINFALL RATES  
TO DRIVE SOME LOCALIZED CONCERNS FOR FLASH FLOODING. THE GREATER  
OVERALL THREAT WILL TEND TO BE OVER THE OH VALLEY WHERE THE  
GREATER MOISTURE IS IN PLACE.  
 
LOCALIZED RAINFALL RATES OF 1 TO 2 INCHES/HOUR AND SOME SPOTTY 2  
TO 3+ INCH RAINFALL AMOUNTS GOING THROUGH EARLY THIS EVENING ARE  
SUPPORTED BY THE LATEST HIRES MODEL CONSENSUS. A LOCALIZED URBAN  
FLASH FLOODING THREAT WILL ALSO BE POSSIBLE GIVEN THE SETUP WHICH  
WOULD INCLUDE SOME AREAS OF NORTHERN VA AND PERHAPS NEAR  
WASHINGTON D.C.  
 
ORRISON  
   
..PLEASE SEE WWW.WPC.NCEP.NOAA.GOV FOR GRAPHIC PRODUCT
 
 
ATTN...WFO...AKQ...ILN...IND...JKL...LMK...LWX...MRX...PBZ...  
RLX...RNK...  
 
ATTN...RFC...ORN...RHA...TIR...NWC...  
 
LAT...LON 39388204 39348065 39267885 39067700 38127723  
37547953 37448042 37138196 36798397 37018495  
37438549 37988549 38398562 38958674 39218578  
39358395  
 
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