MESOSCALE PRECIPITATION DISCUSSION 0002...COR
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
950 PM EDT WED APR 10 2013

CORRECTION FOR SUMMARY TEXT AND GRAPHIC CONTENT
 
AREAS AFFECTED...ERN MISSOURI INTO CNTRL/SRN ILLINOIS AND WRN
INDIANA 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 110149Z - 110749Z
 
SUMMARY...FLASH FLOODING POSSIBLE FROM THE MID-MISSISSIPPI RIVER
INTO CENTRAL AND SOUTHERN ILLINOIS EARLY TONIGHT.

DISCUSSION...AT 00Z...A 1001 MB SURFACE LOW WAS LOCATED JUST NORTH
OF ST. LOUIS WITH A COLD FRONT EXTENDING SSWWD THROUGH MISSOURI
INTO ARKANSAS. RADAR IMAGERY SHOWED AN EXPANSIVE REGION OF
MODERATE TO LOCALLY HEAVY RAIN ALONG AND JUST BEHIND THE COLD
FRONT WHICH IS PROGRESSING TO THE EAST. RADAR ESTIMATED RAINFALL
OVER THE PAST SEVERAL HOURS INDICATES 1 TO 3 INCHES HAS FALLEN
FROM NEAR ST. LOUIS MO...NEWD TOWARD CHAMPAIGN IL. BLENDED TPW
IMAGERY SUGGESTS 1.25 TO 1.50+ INCHES OF PWAT EXTENDS ALONG THE
MID MISSISSIPPI VALLEY INTO SOUTHERN ILLINOIS...AND IS MOVING
NORTH.

AS WE HEAD INTO THE OVERNIGHT HOURS...SHORT TERM MODEL GUIDANCE
SUGGESTS 1.50+ INCH PWATS WILL ADVECT NWD INTO CNTRL ILLINOIS AND
WRN INDIANA VIA AN INCREASING LLJ AHEAD OF THE SLOW MOVING SURFACE
LOW THROUGH 06Z. LIFT THROUGH THE COLUMN SHOULD BE AIDED WITH
INCREASING UPPER DIFLUENCE AHEAD OF AN APPROACHING LARGE SCALE
UPPER TROUGH. RAINFALL RATES EXCEEDING 1 IN/HR ARE EXPECTED AND
THE FLASH FLOOD RISK WILL INCREASE GIVEN THE AFOREMENTIONED
RAINFALL ACROSS ILLINOIS AND FFG VALUES OF 1.5 IN / 3HR.


ATTN...WFO...IND...PAH...LOT...ILX...LSX...

LAT...LON   37358900 37478957 38039019 38989050 39938983 40358901
            40588810 40518724 39448722 38338793 37358900