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000
FOUS30 KWBC 240039
QPFERD

EXCESSIVE RAINFALL DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
838 PM EDT THU MAY 23 2013

...VALID 00Z FRI MAY 24 2013 - 00Z SAT MAY 25 2013...
...REFERENCE AWIPS GRAPHIC UNDER...DAY 1 EXCESSIVE RAINFALL...


SLIGHT RISK OF RAINFALL EXCEEDING FFG TO THE RIGHT OF A LINE FROM
45 N MSV 30 E BGM 10 NE BGM 20 E ITH 25 SSE SYR 15 S UCA
20 ESE UCA 25 ENE RME 30 SSW SLK 25 WNW SLK 10 E MSS CMBR
10 ESE CMLI CXBO 35 SSE CWNH 35 SW FVE 55 NNW MLT 50 NW MLT
20 NW GNR 35 WSW GNR 40 NNE BML 30 N BML 20 NNW BML 10 S 1V4 VSF
20 E AQW 15 ESE PSF 25 SSW PSF 25 SW PSF 45 N MSV.


W TEXAS...

SOME CONCERN EXISTS DURING THE OVERNIGHT FOR POTNL HEAVY CNVTV
RAINS MOST NOTABLY ALONG OUTFLOW BNDRY WHICH WAS SLOWED AND BECOME
E/W SOUTH OF LBB TO NEAR DYS AS OF 00Z.   SFC DATA SHOWS 20KT S TO
SELY FLOW CONTINUING TO FEED INTO THE BNDRY WITH PWS NEAR 1.25
INCHES POOLED ALONG THE BNDRY.  SATL DATA SHOWSWEAK S/WV ENERGY
LIFTING NEWD FROM NW MEX TOWARD WRN TX WHICH SHOULD CONTINUE TO
HELP DVLPG TSTMS ACS A LARGE PORTION OF W TX..THOUGH PRESENCE OF
OUTFLOW BNDRY COULD HELP PROVIDE A MORE FAVORABLE FOCUS FOR
ORGANIZED ACTIVITY.  WITH OUTFLOW BNDRY BECOMING MORE OR LESS
STATIONARY UNDER AN UPR RIDGE AND WEAK STEERING FLOW ALOFT..THE
POTNL FOR SLOW MOVING ORGANIZED CELLS AND POTNL MCS DVLPMENT IS
SOMEWHAT ENHANCED.  RECENT 1 HR RAINFALL AMOUNTS CLOSE TO 2 INCHES
HAVE BEEN REPORTED..AND SUSPECT SOME SHORT TERM AMOUNTS OVER 3
INCHES OR MORE CAN BE EXPECTED.  FFG VALUES ARE QUITE HIGH ACRS
THIS REGION..BUT WHERE STATIONARY ACTIVITY DVLPS...BELIEVE AMOUNTS
COULD APCH OR EXCEED GUIDANCE VALUES IN SOME ISOLD SPOTS.

EASTERN TO NORTHEASTERN NY---PORTIONS OF WESTERN TO NORTHERN NEW
ENGLAND

TRIMMED WRN PORTION OF EARLIER OUTLOOK AREA WHERE HEAVY RAIN
THREAT HAS DIMINISHED WITH PROGRESSION OF HEAVIER FRONTAL PCPN
BAND OVER NY STATE.  OTHERWISE..PREVIOUS FORECAST REASONING IS
STILL VALID.

MODELS ARE SHOWING FAIRLY GOOD AGREEMENT WITH THE AMPLIFICATION OF
STRONG HEIGHT FALLS MOVING SOUTHEASTWARD FROM THE LOWER LAKES AND
INTO A CLOSED LOW OVER THE MID ATLANTIC TONIGHT INTO FRIDAY.  PW
VALUES AHEAD OF THIS AMPLIFYING TROF WILL REMAIN MUCH ABOVE
AVERAGE---2.0-2.5+ STANDARD DEVIATIONS ABOVE THE MEAN FROM
PORTIONS OF THE MID ATLANTIC---EASTERN NY AND INTO NEW ENGLAND.
CONVECTION DEVELOPING THIS AFTERNOON IN SEVERAL LINES AHEAD OF
THIS AMPLIFYING UPPER TROF AND ASSOCIATED FRONTAL BOUNDARY WILL
LIKELY BECOME BETTER ORGANIZED IN A REGION OF STRENGTHENING
FRONTAL CONVERGENCE AND VERY FAVORABLE RIGHT ENTRANCE REGION JET
DYNAMICS---SUPPORTING POTENTIAL FOR FAIRLY WIDESPREAD HEAVY
CONVECTIVE RAINFALL POTENTIAL.  A SLIGHT RISK WAS DEPICTED OVER
AREAS OF RELATIVELY LOW FFG VALUES FROM EASTERN TO NORTHEASTERN
NY---PORTIONS OF WESTERN AND NORTHERN NEW ENGLAND--- FOR THIS
ENHANCING CONVECTION WITH ISOLATED SHORT TERM PRECIPITATION
AMOUNTS OF 1-2"+ POSSIBLE.


SULLIVAN
$$