MESOSCALE PRECIPITATION DISCUSSION 0242
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
556 PM EDT THU MAY 26 2016
 
AREAS AFFECTED...EASTERN AR...WESTERN TN...NORTHERN MS...NORTHERN
AL 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 262154Z - 270154Z
 
SUMMARY...A STRONG LINE OF THUNDERSTORMS WITH VERY HEAVY RAINFALL
IS EXPECTED TO RAISE THE THREAT OF FLASH FLOODING OVER PARTS OF
THE REGION.  HOURLY RAINFALL RATES ON THE ORDER OF 2 INCHES PER
HOUR IS LIKELY WITH THE HEAVIEST CONVECTION THROUGH 9PM THIS
EVENING.

DISCUSSION...THE LATEST SATELLITE AND RADAR IMAGERY OVER WESTERN
KENTUCKY AND TENNESSEE SHOW A PERSISTENT MCS THAT IS SLOWLY
PROPAGATING TO THE SOUTH.  THIS COMPLEX OF STORMS HAS ALREADY
PRODUCED FLASH FLOODING ACROSS PARTS OF SOUTHEAST MISSOURI,
SOUTHERN ILLINOIS, AND WESTERN KENTUCKY EARLIER THURSDAY
AFTERNOON.  SCATTERED STORMS THAT HAVE DEVELOPED SOUTH OF THE MCS
ARE MOVING TOWARDS THE NORTHEAST AND THE POTENTIAL EXISTS FOR
MULTIPLE CELL MERGERS AND AREAS OF ENHANCED CONVECTION AND HEAVY
RAINFALL RATES.  MOIST SOUTHERLY FLOW WITH SURFACE DEWPOINTS IN
THE LOW 70S AND MLCAPES NEAR 3000 J/KG WILL ALSO CREATE A
FAVORABLE ENVIRONMENT FOR HEAVY RAINFALL.

THE LATEST HI-RES MODEL RUNS GENERALLY SUPPORT THE IDEA OF 1 TO 3
INCHES OF RAINFALL OVER THE NEXT FEW HOURS, WITH THE SPC WRF
HAVING SOME OF THE HIGHER QPF AMOUNTS WITH THIS ACTIVITY.  GIVEN
THE LATEST RADAR TRENDS, THIS APPEARS TO BE REALISTIC AT THIS
TIME.  THE LATEST HRRR RUNS APPEAR TO BE SLIGHTLY TOO FAR NORTH
WITH THIS MCS.  THE RELATIVELY SATURATED GROUND AND LOWER FLASH
FLOOD GUIDANCE VALUES OVER NORTHEAST ARKANSAS AND WESTERN
TENNESSEE ALSO INCREASE THE RISK OF FLASH FLOODING, INCLUDING THE
GREATER MEMPHIS AREA.

HAMRICK

ATTN...WFO...BMX...HUN...JAN...LZK...MEG...OHX...PAH...

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

LAT...LON   36518724 36268673 35588645 34878658 34378698 
            34108767 34008874 33998984 33989121 34179184 
            34589231 35219258 35729258 36149238 36409200 
            36489048 36498886