Mesoscale Precipitation Discussion 1076
NWS Weather Prediction Center College Park MD
1027 AM EST Fri Dec 28 2018

Areas affected...Southern AL...Southwest GA...Central/Western FL
Panhandle

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

Valid 281527Z - 282127Z

Summary...Localized flash flooding will be possible into this
afternoon where convection trains in an anomalously high moisture
environment.

Discussion...As of 1530z, radar imagery showed a line of
thunderstorms still organized across portions of GA, southeast AL
and western FL panhandle. The environment remains supportive for
convection with broad upper level divergence and convergence in
the lowest levels. PWATs per latest GPS blend show values as high
as 1.6" across FL panhandle within a belt of strong 850 mb
moisture transport.

As the line of storms tracks eastward through this afternoon, the
southern portions of the line are expected to stall/slow and
become more aligned with the mean flow, suggesting potential for
training convection. This is expected to occur in an instability
axis where SBCAPE 1000-2000 J/kg is possible. This should lead to
an uptick in rainfall rates into the afternoon hours. So, the
combination of increased duration and rain rates suggest the
potential for hourly totals as high as 1.0-1.5" with 6-hour totals
ending 21z 2-4". Antecedent conditions are somewhat wet, with
14-day departures from normal around 150-200 percent, so the 1-hr
and 3-hr FFG may be realized in localized spots. As a result, some
instances of flash flooding will be possible.

Taylor

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

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

LAT...LON   33238368 32928305 32458309 31888329 31598358
            31098413 30048522 30358618 30388676 30308774
            31208676 31968577 32658526