

205 

AWUS01 KWNH 100544

FFGMPD

PAZ000-NJZ000-DEZ000-MDZ000-VAZ000-DCZ000-WVZ000-100943-



MESOSCALE PRECIPITATION DISCUSSION 0098

NWS WEATHER PREDICTION CENTER COLLEGE PARK MD

144 AM EDT MON JUN 10 2013



AREAS AFFECTED...NRN VA...D.C....CENTRAL MD INTO SERN PA



CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE



VALID 100543Z - 100943Z



SUMMARY...FLASH FLOOD THREAT IS INCREASING AS NOCTURNAL CONVECTION

EXPANDS WITHIN A VERY MOIST ENVIRONMENT OVER THE NEXT SEVERAL

HOURS.



DISCUSSION...RECENT RADAR TRENDS HAVE SHOWN AN UPTICK IN

CONVECTION WITHIN A VERY MOIST ENVIRONMENT CHARACTERIZED BY

PRECIPITABLE WATER VALUES OF 1.5 TO 1.75 INCHES PER BLENDED TPW

SATELLITE PRODUCT. CELLS ARE GENERALLY MOVING FROM SSW TO NNE

WITHIN THE MEAN FLOW AHEAD OF AN UPPER TROUGH  MOVING INTO THE

OHIO VALLEY THIS MORNING.



LITTLE CHANGE IS EXPECTED TO OCCUR TO THE STEERING FLOW AND RECENT

CONVECTIVE DEVELOPMENT JUST WEST OF THE RICHMOND METRO AREA IS

EXPECTED TO TRACK NNEWD OVER THE WASHINGTON D.C. METRO AREA. FFG

VALUES ARE RELATIVELY LOW DUE TO RECENT RAINS ASSOCIATED WITH

POST-TROPICAL ANDREA...ON THE ORDER OF 1 IN/HR...WHICH ARE LIKELY

TO BE MET WITHIN THE THREAT AREA THROUGH AT LEAST 1000 UTC.



OTTO



...PLEASE SEE WWW.WPC.NCEP.NOAA.GOV FOR GRAPHIC PRODUCT...



ATTN...WFO...PHI...AKQ...CTP...LWX...



ATTN...RFC...MARFC...



LAT...LON   37907822 38467838 39767731 40277626 40467527 39787514

            38507622 37717753 37907822 


