MESOSCALE PRECIPITATION DISCUSSION 0538
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
513 PM EDT THU OCT 01 2015
 
AREAS AFFECTED...SE GEORGIA...N FLORIDA 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 012112Z - 020212Z
 
SUMMARY...HIGHLY EFFICIENT POTENTIALLY REPEATING CELLS CAPABLE OF
RATES OVER 2.5"/HR COULD PRODUCE POSSIBLE FLASH FLOODING.

DISCUSSION...DIGGING UPPER LEVEL TROF FROM THE NORTHWEST CONTINUES
TO AMPLIFY RIDGING AND INCREASED DIVERGENCE ALONG THE EASTERN
BASED OF THE OVERALL TROF COINCIDENT WITH THE STRONG JET ENTRANCE.
 THIS EXCELLENT EVACUATION ALOFT SHOULD SUPPORT STRONG MAINTAINED
UPDRAFTS WITH THE POTENTIAL OF 'WEDGE' COMPLEX(S) WHERE THE
BALANCE OF UPSTREAM DEVELOPMENT AND CELL MOTIONS EQUALIZE FOR
SMALL POCKETS OF VERY HIGH TOTALS...PARTICULARLY WITH STRONGER
CELLS.  THE LOWER LEVEL ENVIRONMENT IS QUITE CONDUCIVE FOR THESE
STRONG HIGHLY EFFICIENT RAINFALL PRODUCERS WITH CLEAR SKIES
EARLIER TODAY FOR INSTABILITIES FOR SBCAPES TO SURGE OVER 3000
J/KG WITHIN A VERY DEEP/MOIST PROFILE AS SEEN IN THE 18Z JAX
SOUNDINGS (AND 18Z KCHS - WITHOUT SOLAR INSOLATION).  TPWS ARE IN
EXCESS OF 2.0" AND GIVEN THE OVERALL LOW LEVEL FLOW...WHICH IS
QUITE COMPLEX ALLOWING FOR A LARGE AREA OF STRONG MOISTURE
CONVERGENCE.  THE NORTHEASTERLY DEEP TROPICAL MOISTURE ENVIRONMENT
BEGINS TO SLACKEN OVER SE GA WITH 15-20 KTS REDUCING TO 5-10
KTS...LEADING TO MASS PILE-UP CONVERGENCE.  ADDITIONALLY VISIBLE
LOOP SHOWS VERY STRONG CONFLUENT FLOW FROM NWLY CU BANDS OVER SW
GA MERGING WITH THE NELY FLOW ACROSS SE GA...AND ENE OR EVEN ELY
FLOW OFF THE ATLANTIC INTO NORTHERN GA.   THIS HAS LEAD TO LARGE
AREAS OF MOISTURE CONVERGENCE AND FLUX FOR NEW CELL INITIATION
THROUGHOUT THE AREA OF DISCUSSION AND SHOULD MAINTAIN CELLS FOR
SOME TIME.  GOES SOUNDER PWS...ALSO SHOW A SLIGHT DRYING ON THE
WESTERN SIDE OF GA WITH THE APPROACH OF THE UPPER LEVEL S/W...THIS
DRY AIR HAS ALREADY INTRUDED INTO SOME CORES OVER S GA...AIDING
SOME OUTFLOWS. THESE OUTFLOWS APPEAR TO HAVE THE POTENTIAL TO
REINFORCE OTHER COMPLEXES AND MST FLUX TOO.

GIVEN ALL THESE FACTORS OF BACKBUILDING AND CELL MERGERS IN A HIGH
MOIST ENVIRONMENT ...CELLS WITH RATES OVER 2.5-3"/HR ARE POSSIBLE
WITH THE POTENTIAL FOR COMPOUNDED TOTALS THAT MAY NEAR FFG VALUES
BUT GIVEN HIGH RATES COULD TOTAL QUICKLY FOR SOME ISOLATED FLASH
FLOODING CONCERNS. 

MANY HI-RES CAMS QUICKLY DIMINISH CONVECTION WITH REDUCTION OF
SOLAR HEATING/REDUCED INSTABILITIES...THE HIGH MOISTURE
ENVIRONMENT AND UPPER LEVEL FORCING MAY MAINTAIN CELLS LONGER THAN
EXPECTED THE EARLY TWILIGHT HOURS...AND EVOLVE TO MORE
STRATIFORM/ISENTROPIC ASCENT STYLE RAINS. 

GALLINA

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

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

LAT...LON   32758191 32318126 31898116 30838173 30318229 
            29968314 30328384 31198461 32608471 31988309