MESOSCALE PRECIPITATION DISCUSSION 0421
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1214 AM EDT TUE OCT 14 2014
 
AREAS AFFECTED...FLORIDA PANHANDLE INTO ERN ALABAMA / WRN GEORGIA 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 140413Z - 141013Z
 
SUMMARY...RELATIVELY NARROW BANDS OF HEAVY RAIN WILL PERSIST OUT
AHEAD OF AN APPROACHING SQUALL LINE THROUGH 10Z WITH POSSIBLE
FLASH FLOODING. INSTABILITY SUPPORTIVE OF RAIN RATES OF UP TO 2
IN/HR SHOULD REMAIN WITHIN ~150 MILES OF THE GULF COAST.

DISCUSSION...04Z RADAR AND SURFACE OBSERVATIONS SHOWED A COLD
FRONT STRETCHING THROUGH ERN MISSISSIPPI AND LOUISIANA WITH A QLCS
OUT AHEAD OF THE FRONT ACROSS CNTRL ALABAMA MOVING EAST AT ABOUT
20-25 KTS. RADAR FROM KTLH AND KEVX HAVE BEEN SHOWING NARROW
STREAKS OF HEAVY RAIN...ROUGHLY 5-10 MILES WIDE...WITH RADAR
ESTIMATED TOTALS OF 3-4 INCHES IN THE PAST 3 HOURS...MOST NOTABLY
ACROSS WRN LIBERTY AND FRANKLIN COUNTIES. 

WITHOUT REPEATING MUCH OF WHAT WAS STATED IN A RECENT SPENES
MESSAGE FROM 0241Z...THE ENVIRONMENT CHARACTERIZED BY PWATS 1.75
TO 2.25 INCHES...30-50 KTS LOW LEVEL FLOW WITH LITTLE DIRECTIONAL
SHEAR AND EXCELLENT DIFFLUENCE ALOFT WILL CONTINUE THROUGH THE
NIGHT. 

EVEN THE BETTER PERFORMING HI-RES MODELS CONTINUE TO BE ABOUT 3
HOURS SLOW WITH THE HEAVY RAIN...BUT THEY AGREE THAT AVAILABLE
INSTABILITY GREATER THAN 1000 J/KG WILL REMAIN WITHIN 150 MILES OF
THE COAST THROUGH 10Z. INDICATIONS ARE THAT NARROW AXES OF HEAVY
RAIN WILL LIKELY CONTINUE WITH WARM ADVECTION ATOP THE REMAINS OF
A WEAKENING POLAR WARM FRONT ACROSS THE ERN GULF OF MEXICO. THE
COVERAGE OF FLASH FLOODING IS NOT EXPECTED TO BE WIDESPREAD ACROSS
THE HIGHLIGHTED THERAT AREA...BUT RAINFALL TOTALS OF 6+ INCHES ARE
POSSIBLE ON A 1 TO 2 COUNTY-WIDE BASIS FROM THE FLORIDA PANHANDLE
INTO SERN ALABAMA AND SWRN GEORGIA.

OTTO

ATTN...WFO...BMX...FFC...MOB...TAE...

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

LAT...LON   32968584 32898495 32398429 31628377 30498383 
            29698432 29378533 29848630 30268723 32288660