MESOSCALE PRECIPITATION DISCUSSION 0104
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
831 PM EDT THU MAR 31 2016
 
AREAS AFFECTED...NERN MISSISSIPPI...NRN ALABAMA INTO SRN TENNESSEE 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 010029Z - 010430Z
 
SUMMARY...FLASH FLOODING IS POSSIBLE IN THE NEXT HOUR OR TWO
ACROSS NRN MISSISSIPPI/ALABAMA INTO TENNESSEE WITH REPEATING
ROUNDS OF CONVECTION FROM SOUTHWEST TO NORTHEAST. ADDITIONAL
RAINFALL AMOUNTS OF 2-3 INCHES IN A SHORT TIME WILL BE POSSIBLE.

DISCUSSION...A LARGELY PROGRESSIVE LINE OF STORMS...ORIENTED FROM
NE TO SW...MOVED THROUGH CNTRL TENNESSEE INCLUDING THE NASHVILLE
METRO AREA BETWEEN 22Z AND 23Z...AND PRODUCED UP TO AN INCH OF
RAIN. THIS HAS SINCE BEEN FOLLOWED BY ADDITIONAL CONVECTION
BLOSSOMING ON THE SOUTHWEST FLANK OF THIS LINE WITH THESE NEW
CELLS MOVING TO THE ENE. MLCAPE REMAINS BEST TO THE SOUTHWEST OF
CNTRL TENNESSEE...WITH VALUES OF 500-1000 J/KG EXTENDING INTO NRN
MISSISSIPPI AND NRN ALABAMA WITH 850 MB FLOW OF 30-40 KTS FROM THE
SSW PER RECENT VAD WIND PROFILE PLOTS. 

WHILE PRECIPITABLE WATER VALUES ARE ONLY 1.1 TO 1.3 INCHES PER GPS
SITES AND THE 00Z BNA SOUNDING...FLASH FLOOD GUIDANCE ACROSS THE
REGION IS ONLY 1-2 IN/HR WHICH IS ALREADY BEING MET PER KHTX DUAL
POL ESTIMATES. GIVEN THE ONGOING CONVECTION ACROSS NRN
MISSISSIPPI/ALABAMA AND SUFFICIENT INSTABILITY REMAINING...SEE NO
REASON FOR CONVECTION TO DIMINISH IN THE SHORT TERM BENEATH
BROAD/STRONG UPPER DIFFLUENCE. THE POTENTIAL FOR ADDITIONAL RAINS
TO REPEAT ACROSS THE MPD THREAT AREA MAY POSE A SHORT TERM FLASH
FLOOD THREAT OVER THE NEXT FEW HOURS WITH AN ADDITIONAL 2-3 INCHES
POSSIBLE. THE HRRR_EXP HAS LIKELY BEEN THE BEST WITH THE CURRENT
EVOLUTION...THOUGH PERHAPS ITS QPF HAS BEEN A BIT TOO FAR NORTH.

OTTO

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

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

LAT...LON   36118463 35498455 34688655 34278839 34328898 
            34648909 35098886 35648792 36108620