Mesoscale Precipitation Discussion 1037
NWS Weather Prediction Center College Park MD
643 PM EST Sun Dec 02 2018

Areas affected...FL panhandle & Southeast GA

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

Valid 022343Z - 030543Z

Summary...Showers and thunderstorms are showing some increase in
coverage as of late.  Hourly totals to 2" with local amounts of 4"
are possible over saturating soils.

Discussion...A shortwave extending from central SC west-southwest
into the western FL panhandle has led to some increasing in shower
and thunderstorm activity from the western Big Bend into southeast
GA with cooling cloud tops noted on recent GOES-16 Clean IR
imagery.  This is occurring within a moisture axis aligned with
unidirectional west-southwesterly flow to the north of a
temperature and dew point gradient.  With some CIN developing per
SPC mesoanalyses, MU CAPE in the region is 1000-2000 J/kg. 
Effective bulk shear is 35-65 kts which should be sufficient to
develop occasional mesocyclones and training bands of convection,
which are expected to be the main heavy rain cause.  Inflow at 850
hPa is west-southwest at 35 knots per VAD wind profiles. 
Precipitable water values are ~1.75" per GPS data.

The mesoscale guidance shows reasonable agreement on local amounts
in the 3-4" range through 06z, with the consensus on the heavy
rain threat entering a lull after 04z.  With CIN developing,
convection could edge more northward of the boundary across the FL
panhandle and southeast GA than currently shown on radar imagery. 
Hourly rain totals to 2" are possible given the above factors. 
This area has received roughly 3-6" of rainfall per radar
estimates thus far, which is saturating area soils.  A flash flood
threat remains for the next 4+ hours.

Roth

ATTN...WFO...CHS...FFC...JAX...TAE...

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

LAT...LON   32438180 32348052 32218056 31758093 31378117
            31128129 30878170 30048376 29778441 29558516
            29568538 29808540 30018568 30268596 30748516
            31728318