Mesoscale Precipitation Discussion 0629
NWS Weather Prediction Center College Park MD
811 PM EDT Fri Aug 10 2018

Areas affected...Florida Panhandle...Extreme Southeast
Alabama....Southern Georgia

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

Valid 110010Z - 110300Z

Summary...Showers and thunderstorms becoming more numerous over
southern Alabama, western Florida and southern Georgia.  Hourly
rain totals to 2" could lead to issues.

Discussion...GOES 16 IR imagery with RBTop enhancement has been
showing a pronounced period of cloud top cooling over parts of
Georgia and western Florida this evening with radar estimates of
rainfall amounts in excess of 2 inches per hour.  Given the
continued cloud-top cooling, and low level flow from the gulf into
the convection, thinking is that 2 to 4 inch amounts will be
possible for the next couple of hours as convection propagates
east/southeast.

The 18Z HREF have probabilities of 1 inch per hour lingering to
between 02Z and 03Z, feel that the flash flooding is possible as
the area of convection moves slowly towards the higher instability
located to its south and east.  Flash Flood Guidance values are
close to 4 inches per 3 hours...so not expecting to have flash
flooding possible for more than a couple of hours before rainfall
rates taper off.  Also aiding the rainfall rates will be ML Cape
on the order of 2000 J per kg and 2500 J per kg before convection
weakens in response to the loss of insolation.

Bann

ATTN...WFO...FFC...JAX...MOB...TAE...

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

LAT...LON   32288287 31448239 30158367 29608530 30078583
            30338648 30438666 30838679 31398608 31498472
            31628404