EXCESSIVE RAINFALL DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
1019 AM EDT TUE APR 19 2011
 
...VALID 15Z TUE APR 19 2011 - 12Z WED APR 20 2011...
...REFERENCE AWIPS GRAPHIC UNDER...DAY 1 EXCESSIVE RAINFALL...
 

SLIGHT RISK OF RAINFALL EXCEEDING FFG TO THE RIGHT OF A LINE FROM
20 SW PRG 10 W OKK 20 NW FWA 20 SW JYM 15 WNW ADG ARB 10 S PTK
VLL MTC 10 ENE DET 10 NNW CXHA 15 ESE TTF 20 ENE TDZ 30 E TDZ
20 NW CLE 15 NNW CGF 25 NE CGF 10 NW HZY 10 NNE HZY 10 SSW ERI
15 SSE ERI 20 ENE GKJ 10 NE FKL 10 SSE FKL 15 SSW FKL 20 SE YNG
20 S YNG 10 WSW CAK 10 SSE MFD 15 SSW MFD 15 NNW OSU 10 SSE MGY
10 SSE CVG 15 NNW FFT 20 SSW FTK 25 SSW EHR 20 SE HSB 15 SW MVN
20 SW ENL 20 W ENL 15 NW SLO 20 WSW 1H2 15 S MTO 20 SW PRG.

 
UPDATE...

CHANGES TO THE PREVIOUS EXCESSIVE RAINFALL POTENTIAL OUTLOOK WERE
TO EXPAND THE AREA NEWD INTO FAR SERN L.P. OF MI...ACRS NERN
OH/FAR NWRN PA AND SLIGHTLY SWD INTO FAR SRN IN AND FAR NWRN KY.  
NO CHANGES IN THE THINKING FROM THE PREVIOUS OUTLOOK.  A CONTINUED
FAVORABLE PATTERN FOR ORGANIZED CONVECTION ALONG AND NORTH OF THE
WARM FRONT PRESSING NWD TO THE NORTH OF THE OH RIVER AND TOWARD
THE LOWER LAKES AND INCREASING ACTIVE CONVECTION LIKELY THIS
EVENING INTO THE OVERNIGHT PERIOD ALONG THE TRAILING CDFNT THAT WL
BE MOVG INTO THE LOWER OH VALLEY. THERE IS POTENTIAL FOR TRAINING
OF CELLS IN A GENERAL W TO E DIRECTION TO THE NORTH OF THE WARM
FRONT...WITH ISOLATED SHRT TERM PCPN AMTS OF 1-2"+ POSSIBLE. THIS
AND ADDITIONAL FRONTAL CONVECTION MOVG EWD LATER TONIGHT MAY
PRODUCE ISOLATED RUNOFF ISSUES.

ORAVEC 


THERE IS SOME CONCERN FOR FLOODING PROBS ACRS PTNS OF THE OH VLY
THIS PD..WITH ORGANIZED OVRRNG CNVCTN MOVG THRU THE REGION RMNDR
OF MON NGT INTO TUE MRNG..BEFORE ANOTHER ROUND OF SIGNIFICANT
CNVCTN MOVS IN TUE NGT.  STRENGTHENING LLJ/WAA IS SUPPORTING THE
ONGOING OVRRNG CNVCTN..WITH SOME ISOLD 1-2 INCH RNFL AMTS PSBL
PTNS OF SRN IL INTO CNTRL/SRN IN AND WRN OH INTO THE TUE MRNG HRS.
 LTR TUE AFTN AND ESP TUE NGT..SRN STREAM H5 S/WV AND ACCOMPANYING
SFC LOW AND CDFNT WL BE PROGRESSING THRU THE OH VLY..ACCOMPANIED
BY MORE ORGANIZED CNVCTN..WITH LRG SCALE LIFT AIDED ADDITIONALLY
BY A FAVORABLE COUPLED UPR JET STRUCTURE.  WITH THIS 2ND ROUND OF
CNVCTN..THERE IS THE POTNL FOR ANOTHER 1-2 INCHES OF RAIN IN LCL
AREAS..LEADING TO PSBLTY THAT BTWN THE 2 RNFL EVENTS..SOME PTNS OF
THE OH VLY WITHIN THE SLGT RISK AREA COULD SEE 2-3+ INCHES OF
RAIN..WHICH COULD LEAD TO SOME FLOODING PROBS.

TERRY
$$