Graphic for MPD #0277

MESOSCALE PRECIPITATION DISCUSSION 0277
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
910 PM EDT SAT MAY 27 2017

AREAS AFFECTED...SOUTHERN KY...TN...EXTREME SW VA...NW NC

CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY

VALID 280109Z - 280509Z

SUMMARY...STRONG THUNDERSTORMS EXTENDING FROM EXTREME SOUTHEAST MO
AND NORTHEAST AR ACROSS SOUTHERN KY AND TN INTO SOUTHWESTERN VA
AND NC WILL LIKELY PRODUCE SOME FLASH FLOODING DURING THE NEXT
SEVERAL HOURS.

DISCUSSION...THUNDERSTORMS DEVELOPING NEAR THE MO BOOTHEEL AND IN
EXTREME NE AR AND EXTENDING EAST ACROSS KY AND TN ARE PRODUCING
HOURLY RAIN RATES OF 1-1.5"...AND RADAR SHOWS LOCAL ACCUMULATIONS
ALREADY EXCEEDING 2-2.5". THE STORMS ARE DEVELOPING AND MOVING
ALONG A WEAK FRONTAL BOUNDARY ACROSS THE THREAT AREA.

SURFACE DEW POINTS ALONG AND SOUTH OF THE BOUNDARY ARE MAINLY 70
DEGREES F OR HIGHER...WITH PRECIPITABLE WATER VALUES IN THE RANGE
1.4-1.8". SPC MESOANALYSES SHOW THAT MUCAPE RANGES MAINLY FROM
2000-3000 J/KG. THE MOST RECENT RADAR AND SATELLITE IMAGERY SHOW
THAT CELLS ARE BACKBUILDING AT THE WEST END OF THE THREAT AREA. IN
ADDITION THE EASTWARD MOVEMENT OF STORMS ALONG THE BOUNDARY MEANS
THAT SIGNIFICANT TRAINING IS POSSIBLE. STORM DEVELOPMENT WILL
PROBABLY SHIFT SLIGHTLY SOUTHWARD INTO TN...INTO THE REGION OF
HIGHER SURFACE DEW POINTS AND SLIGHTLY HIGHER CAPE...DURING THE
NEXT FEW HOURS.

LOCAL ACCUMULATIONS OF AN ADDITIONAL 2-3" OF RAIN LOOKS LIKELY
ACROSS THE AREA...AND THIS IS SUPPORTED BY THE LAST SEVERAL RUNS
OF THE HRRR.

ADDITIONAL FLASH FLOODING IS LIKELY.

MCDONNAL

ATTN...WFO...GSP...JKL...LMK...MEG...MRX...OHX...PAH...RLX...
RNK...

ATTN...RFC...LMRFC...OHRFC...SERFC...

LAT...LON   37218649 37208221 35878099 35398331 35408698
            35769025 36029106 36509026 36878890


Last Updated: 910 PM EDT SAT MAY 27 2017