MESOSCALE PRECIPITATION DISCUSSION 0009
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1104 AM EDT THU APR 03 2014
 
AREAS AFFECTED...ERN MO...EWD ALONG AND NORTH OF OHIO RIVER INTO
NERN KY / SWRN OH 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 031503Z - 031918Z
 
SUMMARY...A SHORT TERM THREAT FOR FLASH FLOODING WILL CONTINUE
INVOF THE OHIO VALLEY INTO THE EARLY AFTERNOON OVER SATURATED
SOILS DESPITE SOME SIGNS OF A WEAKENING MCS.

DISCUSSION...LATEST RADAR/SATELLITE TRENDS DEPICTED A LARGE
CLUSTER OF THUNDERSTORMS AND EMBEDDED HEAVY RAIN MOVING THROUGH
IL/IN/OH IN CONNECTION WITH A LINGERING MCS FROM THE OVERNIGHT
HOURS. CLOUD TOPS HAVE BEEN WARMING ACROSS IL...BUT CONTINUE TO
COOL WITH RENEWED CONVECTIVE DEVELOPMENT ACROSS PORTIONS OF IN.
SURFACE OBSERVATIONS SHOWED AN OUTFLOW BOUNDARY SOUTH OF THE
CONVECTION AT 1400 UTC FROM JUST NORTH OF TBN TO CGI TO
AJG...WHICH HAS STALLED OVER ERN MO AND SRN IL WHILE CONVECTION
HAS CONTINUED TO REGENERATE TO ITS NORTH OVER SRN IL. BLENDED TPW
PRODUCT ALONG WITH VAD WIND PROFILE PLOTS INDICATED WINDS OF 40-50
KT FROM THE SSW ALONG THE WRN OHIO VALLEY WITHIN AN AXIS OF 1.25
TO 1.5 INCH PRECIPITABLE WATER VALUES.

RAP FORECASTS INDICATE THE LOW LEVEL JET WILL CONTINUE TO MAINTAIN
INTENSITY WHILE ADVECTING MOISTURE NWD ATOP THE OUTFLOW BOUNDARY
WITHIN A NEARLY SATURATED AIRMASS. RECENT RAINFALL HAS LOWERED
FLASH FLOOD GUIDANCE VALUES BELOW 1 IN/HR FROM E-CNTRL IL INTO
SWRN OH/NRN KY. THE LATEST HRRR AND GEM REGIONAL MODELS SEEM TO BE
HANDING THE EVOLUTION OF THE ONGOING CONVECTION REASONABLY WELL
AND SUGGEST THE HEAVIEST RAIN WILL CONTINUE THROUGH 1900 UTC ALONG
THE SRN PORTION OF THE THREAT AREA. DUE TO THE VERY LOW FFG
VALUES...A CONTINUED RISK OF FLASH FLOODING WILL EXIST INTO AT
LEAST THE EARLY AFTERNOON HOURS.

OTTO

ATTN...WFO...JKL...ILN...LMK...IND...PAH...ILX...LSX...

ATTN...RFC...LMRFC...MBRFC...NCRFC...OHRFC...

LAT...LON   37899083 39459031 39828816 39978641 39908506 39718432
            39248346 38528348 38308444 37868579 37138873 37899083