MESOSCALE PRECIPITATION DISCUSSION 0099
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1129 AM EDT THU JUN 05 2014
 
AREAS AFFECTED...WRN TN...CENTRAL TN...FAR NRN MS AND AL 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 051528Z - 051928Z
 
SUMMARY...SCATTERED THUNDERSTORMS WITH BRIEF HEAVY DOWNPOURS MAY
HAMPER THOSE DEALING WITH THE EFFECTS OF FLASH FLOODING THAT
OCCURRED EARLIER. ADDITIONAL ORGANIZED HEAVY RAIN IS NOT EXPECTED
UNTIL AN MCS ARRIVES FROM THE WEST. THE AXIS OF HEAVIEST RAIN
LATER TODAY IS PREDICTED SOUTH OF THE AREAS THAT FLOODED THIS
MORNING.

DISCUSSION...HIGHER END FLASH FLOODING OCCURRED EARLY THIS MORNING
IN TN...NOTING 7.45 INCHES OF RAIN MEASURED AT LOBELVILLE AND
REPORTS FROM WFO NASHVILLE OF NUMEROUS STRANDED MOTORISTS. THE
EVENT OCCURRED AS 850 MB WINDS CONVERGED ALONG THE EASTERN EDGE OF
UNSTABLE BUT CAPPED AIR OVER ARKANSAS...IN TANDEM WITH MID LEVEL
ASCENT AT THE BACK EDGE OF AN EASTERN U.S. TROUGH. AT 15Z...RADAR
CONTINUED TO SHOW SCATTERED CONVECTION IN WESTERN AND CENTRAL
TN...BUT THE CHARACTER HAD BECOME LOOSELY ORGANIZED WITH MID LEVEL
SUPPORT AND LOW LEVEL INFLOW WANING.

WESTERLY LOW LEVEL INFLOW OF 15-20 KT WILL CONTINUE TO ASCEND OVER
THE ESTABLISHED COLD POOL TO PRODUCE POCKETS OF MODERATE RAIN
THROUGH EARLY AFTERNOON...BUT MODEL GUIDANCE AND RADAR TRENDS
SUGGEST DURATION OVER INDIVIDUAL BASINS WILL BE BRIEF.

TOWARD LATE AFTERNOON...A VERY WELL ORGANIZED MCS IS EXPECTED TO
APPROACH FROM THE WEST. RECENT HRRR RUNS HAD A DECENT HANDLE ON
THE SYSTEM...AND SUGGEST A TRACK DIRECTED ALONG THE DEVELOPING
CAPE GRADIENT INTO SOUTHWEST TN AND ADJACENT NRN MS/AL BEYOND 20Z.
THE SYSTEM WILL MOVE QUICKLY...BUT RAIN RATES ARE LIKELY TO BE
QUITE HIGH AND COULD APPROACH THE 2-INCHES-IN 1-HOUR FLASH FLOOD
GUIDANCE HERE. IT IS DIFFICULT TO ANTICIPATE STRATIFORM REGIONS
AND MCV BEHAVIOR...BUT RAIN OF AT LEAST MODERATE INTENSITY COULD
MOVE BACK INTO HARD HIT AREAS FARTHER NORTH. 

BURKE

ATTN...WFO...OHX...HUN...MEG...

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

LAT...LON   36268762 36418869 36168944 35208993 34798919 34588795
            34448698 34548646 35008619 35688656 36268762