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000
FOUS30 KWBC 181746
QPFERD

EXCESSIVE RAINFALL DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
146 PM EDT SAT MAY 18 2013

...VALID 18Z SAT MAY 18 2013 - 00Z MON MAY 20 2013...
...REFERENCE AWIPS GRAPHIC UNDER...DAY 1 EXCESSIVE RAINFALL...


SLIGHT RISK OF RAINFALL EXCEEDING FFG TO THE RIGHT OF A LINE FROM
30 N BFF 30 SE D07 35 SW JMS 30 E TVF 20 NE VWU 20 SW FOZ
10 N 2P3 20 WSW MML 35 S MHE 40 NNE ONL 20 WSW ONL 15 NW LBF
20 S SNY 10 SSE IBM 30 N BFF.


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

LITTLE CHANGE FM PREVIOUS THINKING..EXCEPT FOR A RAPIDLY LOWERING
CONFIDENCE LVL CONCERNING PLACEMENT. HGT FALLS AND FVBL DIV ALOFT
ASOCTD WITH THE WRN U.S. UPPER TROF WILL GENERATE 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).
UNFORTUNATELY..THE 12Z MODEL QPFS CONTINUE TO DIFFER SGFNTLY BTWN
ONE ANOTHER..AS WELL AS SHOW SGFNT RUN TO RUN CHANGES.  AS A
RESULT..THE ISSUED SLGT RISK FOR THE AREAS WILL BE FAIRLY LARGE
.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...

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
$$