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000
FOUS30 KWBC 181316
QPFERD

EXCESSIVE RAINFALL DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
916 AM EDT SAT MAY 18 2013

...VALID 15Z SAT MAY 18 2013 - 12Z SUN MAY 19 2013...
...REFERENCE AWIPS GRAPHIC UNDER...DAY 1 EXCESSIVE RAINFALL...


SLIGHT RISK OF RAINFALL EXCEEDING FFG TO THE RIGHT OF A LINE FROM
10 NNW HON 9V9 40 ENE IEN 25 NNW IEN 10 ESE RAP 25 WSW D07
30 NNE D07 40 WNW MBG 10 WSW K7L2 25 S K46D 25 NW RDR 25 W CWSU
FGN 40 NNW INL 15 NNW INL 25 N FOZ 25 WSW FOZ 20 NW ADC 20 S 8D3
10 NNW HON.


...NORTHERN PLAINS INTO THE EXTRM UPPER MISSISSIPPI VALLEY...

LITTLE CHANGE FM PREVIOUS THINKING.  PRIMARY THREAT IS FOR THIS
EVNG AND TONIGHT AS HGT FALLS AND FVBL DIV ALOFT ASOCTD WITH THE
WRN U.S. UPPER TROF GENERATES A FAIRLY SIZABLE AREA OF
ASCENT..COINCIDING WITH A DEVELOPING LLJ ~30 KTS AND PW`S ~1.25"
(WHICH IS ABOUT 2 STD DEVIATIONS ABOVE THE NORM). ELEVATED LLVL
MSTR FLUX CONVERGENCE (925-850 MB) IS EXPECTED TO BE ON THE ORDER
OF 2.5-3.0 STD DEVIATIONS ABOVE NORMAL WITH THE ANTICIPATED MCS
TONIGHT PER BOTH THE SREF AND GEFS STANDARDIZED ANOMALIES. MODEL
QPF GUIDANCE STILL VARYING QUITE A BIT WITH RESPECT TO THE EXACT
PLACEMENT OF THE AXIS OF HEAVIEST RAIN HENCE THE ISSUANCE OF A
SLGT RISK FOR A FAIRLY LARGE AREA..WHICH IS ALSO A PRODUCT OF
LOWERING FFG NUMBERS DUE TO LAST NIGHT`S ACTVTY.  AMTS OF 1.50 TO
2.00 INCHES IN A THREE HOUR PD WOULD SEEM QUITE POSSIBLE GIVE THE
MSTR AND FORCING INVOLVED..WITH TOTALS LIKELY TO APCH 4.00 INCHES
THRU THE PD OVR SPOTTY AREAS.


...ALABAMA/GEORGIA...

WHILE SHWRS INVOF AL/GA ARE GRADUALLY WKNG..CANNOT RULE OUT THE
POTENTIAL FOR REDVLPMNT OF CNVCTV RAINS LATER TDA AND TNGT AS A
FVBL LLVL MSTR FLUX CONTINUES INTO THE BACKSIDE OF A MID/UPR LVL
COOL POCKET SUPPORTING INDUCING A REGION OF ISENTROPIC LIFT.  AT
THIS TIME WOULD FAVOR NRN AL AND W CNTRL GA FOR THE MOST ORGANIZED
SHWRS WITH THE MAIN CONCERN BEING THAT SHWRS COULD REPEAT OVR
AREAS SATURATED BY ACTVTY OVR THE PAST 12 HOURS.

KORTY
$$