034
AWUS01 KWNH 100514
FFGMPD
FLZ000-GAZ000-ALZ000-MSZ000-LAZ000-101015-

Mesoscale Precipitation Discussion 0256
NWS Weather Prediction Center College Park MD
114 AM EDT Fri May 10 2024

Areas affected...southern MS/AL, northwestern FL Panhandle and
southwestern GA

Concerning...Heavy rainfall...Flash flooding possible

Valid 100513Z - 101015Z

SUMMARY...Localized flash flooding will be possible through 10Z
from 4+ inch rainfall totals across the southern Gulf Coast
states. The potential for these higher end rainfall totals would
fall in a 2-3 hour window, resulting from west to east training.

DISCUSSION...A couple of thunderstorm clusters were noted on
regional radar imagery at 0445Z, extending from western GA to the
Sabine River Valley. The strongest of the region was located over
eastern LA into MS, with IR cloud tops of -65 to -75 C on 10.3
micron imagery. It was here that a slow moving cold front was
analyzed, with a 1008 mb low in southwestern MS, east of HEZ. More
recent development was noted over south-central AL on convective
outflow. Another remnant outflow boundary, currently not active,
was analyzed from Apalachee Bay into the FL Panhandle and
southeastern AL, where it intersected the advancing outflow
boundary to the north. SPC mesoanalysis data from 04Z showed the
environment ahead of the cold front from central LA into southern
MS/AL contained MLCAPE of 2500 to near 3500 J/kg with weak to
negligible inhibition.

Given the moist (PWATs 1.6 to 2.0 inches) and unstable environment
along with trends in IR satellite imagery, convection is likely to
maintain for at least another few hours. Corfidi vectors and short
term HRRR guidance support that the cluster over LA/MS/AL will
track toward the ESE through 10Z, with periods of west to east
training, especially along the southwestern flank of the expanding
MCS, given its present orientation.

Additional convective development will be possible in the vicinity
of the remnant outflow boundary over southeastern AL into the FL
Panhandle as increasing moisture transport within the 850-700 mb
layer allows for weakening lower level CIN, inferred by area 00Z
ROABs and RAP analysis soundings. While timing of this is
uncertain, recent HRRR guidance suggests development in the 06-08Z
time frame. Should such development occur, it will carry the
potential for short term training, followed by the approach of the
upstream MCS, possibly leading to heavy rainfall totals. The
latest thinking is for portions of the southern Gulf Coast states
to receive 4+ inches of rain in 2-3 hours, which could support
localized areas of flash flooding, especially within urban areas
or other locations of poor drainage.

Otto

...Please see www.wpc.ncep.noaa.gov for graphic product...

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

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

LAT...LON   32478875 32458769 32458616 32358530 31538456
            30488490 30678727 30688959 30759060 30979096
            31299111 31739103 31919022 32068981 32318934