MESOSCALE PRECIPITATION DISCUSSION 0517...CORRECTED
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
948 PM EDT SUN JUL 22 2018

CORRECTED FOR CATEGORY

AREAS AFFECTED...NORTH-CENTRAL NC & SOUTH-CENTRAL VA

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

VALID 230102Z - 230402Z

SUMMARY...THUNDERSTORMS ARE AMASSING ACROSS NORTH-CENTRAL NC. 
HOURLY RAIN TOTALS TO 2" WITH LOCAL AMOUNTS TO 4" ARE POSSIBLE DUE
TO CELL MERGERS/TRAINING.

DISCUSSION...A GROWING MASS OF THUNDERSTORMS IN NORTH-CENTRAL NC
ARE BEING FORCED BY A MESOSCALE WAVE NEAR ASHEBORO AND ITS
ASSOCIATED INVERTED TROUGH.  AN UPPER LEVEL CIRCULATION ACROSS
NORTHWEST SC APPEARS TO BE ENHANCING UPPER LEVEL OUTFLOW. 
EFFECTIVE BULK SHEAR OF 25-30 KTS IS IN THIS REGION, WHICH HAS
ALLOWED A PORTION OF THE THUNDERSTORM AREA TO ALIGN AS A BAND. 
PRECIPITABLE WATER VALUES OF 1.5-1.75" EXIST HERE PER GPS VALUES
AND RAP ANALYSES.  ML CAPE VALUES OF 1500+ J/KG EXIST IN THIS AREA.

AN OUTFLOW BOUNDARY COMING IN FROM THE EAST IS EXPECTED TO LEAD TO
AN ENHANCEMENT IN RAINFALL RATES ACROSS THE REGION DURING THE NEXT
HOUR OR TWO, WHICH MAY TAKE A FEW HOURS TO RESOLVE ITSELF.  THE
18Z HREF PROBABILITIES OF 1"+ IN AN HOUR APPEAR TO HAVE PICKED UP
ON THIS COMPLEX.  HOURLY RAIN TOTALS TO 2" WITH LOCAL AMOUNTS TO
4" ARE EXPECTED BY THE TIME THE THUNDERSTORM COMPLEX FADES.

ROTH

ATTN...WFO...AKQ...GSP...RAH...RNK...

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

LAT...LON   37417921 37087860 35997853 35108000 35188030
            36288022 36977994