MESOSCALE PRECIPITATION DISCUSSION 0667
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1201 AM EDT WED SEP 14 2016
 
AREAS AFFECTED...EXTREME NORTHEASTERN FL PANHANDLE/COASTAL GA... 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 140401Z - 140901Z
 
SUMMARY...TROPICAL STORM JULIA...JUST RECENTLY UPGRADED TO THIS
STATUS...WILL BRING A HEAVY RAINFALL THREAT TO THE EXTREME
NORTHEASTERN FL PANHANDLE UP INTO THE SC COAST. WITHIN THE
MOISTURE RICH AIR MASS...HEAVY DOWNPOURS CAPABLE OF FLASH FLOODING
WILL BE POSSIBLE...PARTICULARLY OVER ANY URBANIZED LOCALES.

DISCUSSION...IR SATELLITE IMAGERY INDICATED MULTIPLE FLARE-UPS
OCCURRING OVER THE UNSTABLE AIR ACROSS THE GULF STREAM.
FURTHER...COOLING CLOUD TOPS WERE ALSO EVIDENT JUST NORTH AND EAST
OF THE CIRCULATION WITH A BAND OF RAINFALL MOVING THROUGH
JACKSONVILLE...FL. IT HAS NOT BEEN PARTICULARLY IMPRESSIVE AS
DUAL-POL RADAR IMAGERY SHOWED HOURLY RAINFALL RATES RAPIDLY
DIMINISHING UPON MOVING INLAND. THE SPC MESOANALYSIS PAGE DID SHOW
DECREASING LEVELS OF BUOYANCY WHICH MAY BE THE REASON FOR THESE
DIMINISHING RAINFALL AMOUNTS. EXPECT THE HEAVIEST RAIN TO
CONCENTRATE VERY NEAR THIS TROPICAL CIRCULATION WITH MANY CAMS
SHOWING 3 TO 5 INCHES ALONG THE COASTAL BORDER OF FL/GA THROUGH
09Z. IN ITS FAVOR IS STRONG 1000-700 MB MOISTURE ADVECTION WITH A
LAYER OF 25 TO 30 KNOT EASTERLY WINDS AS NOTED IN THE 00Z JAX
RAOB. ADDITIONALLY...A VERY MOIST COLUMN IS NOTED WITH NEARLY
SATURATED CONDITIONS ACCOMPANIED BY A PWAT OF 2.36 INCHES WHICH IS
APPROXIMATELY 2 SIGMAS ABOVE CLIMATOLOGY.

TO THE NORTH...MANY OF THE CONVECTIVE ELEMENTS HAVE BEGUN TO SWING
TOWARD THE GA COAST ALTHOUGH MOST OF THESE FEATURES HAVE REMAINED
OFFSHORE. RECENT RAP RUNS HOW STRONG LOW-LEVEL MOISTURE
CONVERGENCE ALONG MUCH OF THE GA COAST. LIKE AREAS TO THE
SOUTH...INSTABILITY IS NOT GREAT WITH MUCAPE VALUES GENERALLY
MAXIMIZING OUT AROUND 1000 J/KG. MODELS SEEM TO FAVOR ENOUGH
DYNAMICAL LIFT OUT OF THE TROPICAL CIRCULATION TO OVERCOME ANY
SHORTCOMINGS TO PRODUCE FAIRLY HEFTY RAINFALL RATES OVERNIGHT.


RUBIN-OSTER

ATTN...WFO...CHS...JAX...

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

LAT...LON   32108134 31848074 31468076 31078095 30318118 
            30198172 30568208 31548202