Flash Flood Guidance
Issued by NWS

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000
AWUS01 KWNH 032002
FFGMPD
SCZ000-FLZ000-GAZ000-ALZ000-040031-

MESOSCALE PRECIPITATION DISCUSSION 0030
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
301 PM EST WED FEB 03 2016

AREAS AFFECTED...FL PANHANDLE...EASTERN GA...SC...

CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE

VALID 032001Z - 040031Z

SUMMARY...CONVECTION CONTINUES TO BE SLOWER MOVING CLOSER TO THE
GULF COAST WITH HOURLY RAINFALL RATES REACHING THE 1 TO 1.50 INCH
RANGE AT TIMES. TO THE NORTH...THE SQUALL LINE HAS BEEN SLIGHTLY
MORE PROGRESSIVE IN NATURE WHICH HAS MITIGATED A MORE APPRECIABLE
FLASH FLOOD THREAT. HOWEVER...ANOMALOUS MOISTURE CONTENT AMIDST
HIGHLY EFFICIENT RAINFALL PROCESSES WILL SUPPORT HEAVY
PRECIPITATION INTO THE EVENING HOURS.

DISCUSSION...A BROAD SHIELD OF MODERATE/HEAVY RAINFALL CONTINUES
TO STRETCH ACROSS A SIGNIFICANT PORTION OF THE SOUTHEASTERN U.S.
AN ELONGATED SQUALL LINE SPANNED MUCH OF THE WESTERN FRINGE OF THE
OUTLOOK AREA WITH A FEW CELLS FIRING IN ADVANCE OF THE LINE. THE
LATTER CONVECTION APPEARS TO BE WITHIN THE PLUME OF HIGHER
INSTABILITY WITH THE 19Z RAP OBJECTIVE ANALYSIS SUPPORTING UP TO
1000 J/KG OF MUCAPE. RECENT SATELLITE IMAGERY/LIGHTNING DATA
SHOWED THE MOST ACTIVE UPDRAFTS WERE ACROSS SOUTHWESTERN
GA/WESTERN FL PANHANDLE WHERE SOME OF THE HIGHER RAINFALL RATES
HAVE BEEN OBSERVED. HOURLY MESONET DATA INDICATED 1.25 TO 1.50
INCH AMOUNTS OVER SOUTHWESTERN GA WHICH SHOULD CONTINUE WHERE
CONVECTION THRIVES.

THE SITUATION TO THE NORTH IS A BIT MORE UNCERTAIN AS THE
INSTABILITY IS MUCH WEAKER WITH RAINFALL RATES LOWER THAN AREAS
CLOSER TO THE GULF COAST. HOWEVER...ANOMALOUS MOISTURE CONTINUES
TO PUMP NORTHWARD IN ADVANCE OF THE SLOW-MOVING COLD FRONT. GIVEN
HIGHLY EFFICIENT RAINFALL PROCESSES AND SUFFICIENT DYNAMICAL
SUPPORT...CANNOT RULE OUT ISOLATED HYDROLOGIC ISSUES ACROSS THE
NORTHERN EXTENT OF THE MPD AREA.

AS HAS BEEN THE CASE MUCH OF THE DAY...CAMS HAVE BEEN TO SLOW TO
ADVECT THE ONGOING ACTIVITY EASTWARD. THE 18Z HRRR PRESENTS THE
CLOSEST PICTURE TO REALITY AT THIS POINT WHICH FAVORS A BROAD AXIS
OF 1 TO 2 INCHES OF RAIN THROUGH 00Z. OF COURSE HIGHER AMOUNTS ARE
LIKELY WHERE CONVECTION TRAINS.

RUBIN-OSTER

...PLEASE SEE WWW.WPC.NCEP.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...CAE...CHS...FFC...GSP...JAX...TAE...

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

LAT...LON   34688101 34448036 33858007 33268017 32488063
            30928219 29638414 29328583 29968639 31038513
            32898318 33898214 34568147


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