Graphic for MPD #0536

MESOSCALE PRECIPITATION DISCUSSION 0536
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
544 PM EDT SAT JUL 22 2017

AREAS AFFECTED...SE OHIO...N WEST VIRGINIA...SW PENNSYLVANIA...W
MARYLAND...NW VIRGINIA

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

VALID 222143Z - 230243Z

SUMMARY...THUNDERSTORMS WITH PERSISTENT HEAVY RAINFALL ARE
EXPECTED TO CONTINUE FROM EASTERN OHIO AND ACROSS NORTHERN WEST
VIRGINIA THROUGH THE EVENING HOURS.  HOURLY RAIN RATES UP TO 2
INCHES OVER SATURATED GROUNDS COULD CAUSE SOME ADDITIONAL FLOODING
ISSUES.

DISCUSSION...DOPPLER RADAR IMAGERY ACROSS THE CENTRAL APPALACHIANS
AT 530PM LOCAL TIME WAS INDICATING MULTIPLE ROUNDS OF TRAINING
CONVECTION FROM SOUTH OF COLUMBUS, OHIO, TO NORTHERN VIRGINIA. 
RECENT ECHO TOP DATA IS INDICATING STORMS REACHING 55KFT WITH
EXPANDING COLD CLOUD TOPS PER LATEST INFRARED SATELLITE IMAGERY. 
MLCAPE OF 2000 TO 3000 J/KG EXISTS SOUTH OF THE CONVECTION PER THE
LATEST SPC MESOANALYSIS, AND PWS ARE IN THE 1.75 TO 2.15 INCH
RANGE IN THIS REGION.  FLASH FLOOD GUIDANCE VALUES ARE ALREADY
SIGNIFICANTLY REDUCED OVER SOUTHEAST OHIO AND ESPECIALLY NORTHERN
WEST VIRGINIA OWING TO RECENT RAINFALL, AND THIS IS WHERE THE
GREATEST FLASH FLOOD THREAT RESIDES THIS EVENING.

RECENT HI-RES MODEL GUIDANCE, INCLUDING THE HRRR, ARW, AND NMMB,
SUGGESTS THE POTENTIAL FOR ISOLATED 3+ INCH AMOUNTS THROUGH 02Z
THIS EVENING, AND GIVEN RECENT RADAR AND SATELLITE TRENDS, THIS IS
CERTAINLY WITHIN THE REALM OF POSSIBILITY.

HAMRICK

ATTN...WFO...CLE...CTP...ILN...LWX...PBZ...RLX...

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

LAT...LON   40388203 40387999 40267794 39547759 38487814
            38357885 38387957 38468049 38658183 38858326
            39328402 39968392 40318341


Last Updated: 544 PM EDT SAT JUL 22 2017