MESOSCALE PRECIPITATION DISCUSSION 0057
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1015 AM EDT WED MAY 14 2014
 
AREAS AFFECTED...CENTRAL GULF COAST 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 141414Z - 142014Z
 
SUMMARY...INCREASING LOW-LEVEL INFLOW FROM THE GULF OF MEXICO, AN
APPROACHING FRONT FROM THE WEST, AND AN APPROACHING CONVERGENCE
ZONE FROM THE GULF OF MEXICO COULD LEAD TO REGIONAL FLASH FLOODING
OVER THE NEXT SEVERAL HOURS.

DISCUSSION...A 14Z SURFACE ANALYSIS FEATURED A WAVY FRONTAL
BOUNDARY MOVING INTO SOUTHEAST LA AND SOUTHWEST MS.  THE 00Z ARW
IMPLIES CAPE VALUES ALONG THIS FEATURE MEET THE THRESHOLD FOR THE
WET MULTI-CELL ENVIRONMENT (1000+ J/KG).  MEANWHILE, LOW-LEVEL
INFLOW CONVERGES SOMEWHAT TO THE SOUTHEAST IN THE VICINITY OF THE
WESTERN FL PANHANDLE/SOUTHERN AL, AHEAD OF A NORTHWARD-MOVING
CONVERGENCE ZONE IN THE NORTHERN GULF OF MEXICO (SEEN ON RAPID
SCAN SATELLITE IMAGERY), AND IS EXPECTED TO INCREASE DURING THE
DAY TODAY, REACHING THE THRESHOLD FOR THE WET MULTI-CELL
ENVIRONMENT (25+ KTS OF 0-3 KM SHEAR) BETWEEN LATE THIS MORNING
AND EARLY THIS AFTERNOON.  PRECIPITABLE WATER VALUES ARE EXPECTED
TO BE IN THE NEIGHBORHOOD OF 1.75-2", WITHIN THE 90-99TH
PERCENTILES FOR MID-MAY FOR THE REGION.

THERE IS A GOOD SIGNAL IN THE MESOSCALE GUIDANCE (QPF-WISE) FOR
HEAVY RAINS, ON THE ORDER OF 3-6" LOCALLY OVER SEVERAL HOURS
WITHIN THIS REGION, THOUGH THE GUIDANCE SHOWS LITTLE OVERLAP IN
THE EXACT LOCATION.  CURRENT SCATTERED THUNDERSTORM ACTIVITY
SHOULD BECOME MORE WIDESPREAD, AND LOCALLY TRAIN WITHIN THIS
REGION.  THIS LED TO A FAIRLY BROAD AREA DEPICTED.  HOURLY
RAINFALL RATES SHOULD REACH 2" AN HOUR OVER THE NEXT SEVERAL
HOURS, WITH LOCAL SPOTS RECEIVING A QUICK 3-6", WHICH COULD LEAD
TO REGIONAL FLASH FLOODING.

ROTH

ATTN...WFO...TAE...BMX...MOB...JAN...LIX...

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

LAT...LON   29668511 30358655 30138782 30068901 29888914 29558950
            29208890 29008901 29189044 30229043 31538961 32558844
            32558673 31498527 29668511