MESOSCALE PRECIPITATION DISCUSSION 0464
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
916 AM EDT TUE JUL 11 2017

AREAS AFFECTED...CENTRAL IL...CENTRAL IN...WESTERN OH

CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE

VALID 111316Z - 111716Z

SUMMARY...THE THREAT FOR SOME ADDITIONAL FLASH FLOODING CONTINUES
AS MULTIPLE ROUNDS OF THUNDERSTORM ACTIVITY MOVE THROUGH THE
REGION DURING THE MID TO LATE MORNING HOURS.

DISCUSSION...CLUSTERS OF HEAVY SHOWERS AND THUNDERSTORMS CONTINUE
TO DEVELOP AND PERSIST ACROSS PORTIONS OF CENTRAL ILLINOIS AND
ALSO CENTRAL INDIANA THIS MORNING SOUTH OF A FRONTAL ZONE AND
SURFACE LOW.  ECHO TOPS OF 50KFT HAVE BEEN DEPICTED BY REGIONAL
DOPPLER RADARS AND THIS IS INDICATIVE OF VIGOROUS UPDRAFTS. 
FAVORABLE INSTABILITY IS IN PLACE WITH MUCAPE ON THE ORDER OF 1500
TO 2000 J/KG AS DEPICTED BY THE LATEST SPC MESOANALYSIS.  COUPLED
WITH PWS NEAR 2 INCHES AND ABOUT 30 KNOTS OF CONVERGENT 850MB
INFLOW SOUTH OF A FRONTAL BOUNDARY IS CREATING A FAVORABLE
ENVIRONMENT FOR HEAVY RAINFALL AND TRAINING CONVECTION.  THE
THREAT OF FLASH FLOODING IS OF GREATER CONCERN FOR CENTRAL INDIANA
AS THE CONVECTION APPROACHING FROM ILLINOIS TRACKS OVER SATURATED
GROUND FROM THE STORMS THAT ARE CURRENTLY ONGOING. 

CONDITIONS WILL LIKELY REMAIN CONDUCIVE FOR ADDITIONAL CONVECTION
TO DEVELOP AND LOCALLY BACKBUILD WITHIN THIS REGION THROUGH AT
LEAST MIDDAY.  RAINFALL RATES OF NEARLY 2 INCHES PER HOUR WILL BE
POSSIBLE WITH THE STRONGEST CONVECTION.  THE LATEST HI-RES
GUIDANCE APPEARS TO BE UNDERDONE WITH RAINFALL AMOUNTS, ESPECIALLY
WITH THE ACTIVITY CURRENTLY OVER INDIANA.  GIVEN THE PRIOR HEAVY
RAINFALL ACROSS PARTS OF THIS AREA, THE ADDITIONAL RAIN WILL
CONTINUE TO PROMOTE CONCERNS FOR RUNOFF AND FLASH FLOODING.

HAMRICK

ATTN...WFO...DVN...ILN...ILX...IND...IWX...LOT...LSX...

ATTN...RFC...NCRFC...OHRFC...

LAT...LON   41358781 41268650 41118537 40818440 40378378
            39658350 39138365 38918420 38928520 38998625
            39058749 39138907 39309025 39459088 39879116
            40479114 40679104 40929077 41209021 41348923