MESOSCALE PRECIPITATION DISCUSSION 0249
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
953 PM EDT FRI JUN 19 2015
 
AREAS AFFECTED...SRN IL...SRN IN...WRN AND CENTRAL KY...WRN TN 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 200151Z - 200800Z
 
SUMMARY...HEAVY RAIN THREAT WITH TROPICAL DEPRESSION BILL WILL
CONTINUE SLOWLY EASTWARD INTO THE OVERNIGHT HOURS.

DISCUSSION...TROPICAL DEPRESSION BILL WAS CENTERED NEAR THE BORDER
OF SOUTHEAST MO AND EXTREME SOUTHERN IL AND IT WAS CONTINUING TO
MOVE TOWARDS THE EAST-NORTHEAST.  THE FOCUS FOR HEAVIEST RAINFALL
STILL LOOKS TO BE WHERE A RIBBON OF ANOMALOUSLY MOIST 850 MB FLOW
RIDES UP AND OVER A LOW LEVEL BOUNDARY.  THIS CONTINUES TO
CORRESPOND TO THE BEST DEFORMATION ZONE AS SHOWN BY THE GLOBAL AND
CONVECTION ALLOWING MODELS AT MID LEVELS. 

SPC MESO ANALYSIS SHOWS MUCAPES HAVE DROPPED INTO THE 500 J PER KG
TO 1000 J PER KG RANGE OVER PARTS OF THE SOUTHERN OH VALLEY.  PART
OF THIS AIRMASS WILL CONTINUE TO BE DRAWN NORTHWARD INTO PARTS OF
KY/IN.  00Z RAOB AT KBNA WAS 1.73 INCHES...WHICH WAS ON PAR WITH
THE SATELLITE DERIVED TOTAL PRECIPITABLE WATER VALUES. SATELLITE
PW VALUES OF 2 INCHES OR MORE WERE LOCATED OVER WRN TN INTO WRN
KY.  

THUS THE POTENTIAL FOR RAINFALL RATES OF 2 INCHES PER HOUR
CONTINUES IN THE HEAVIEST CONVECTION. ADDITIONAL RAINFALL TOTALS
OF 1-3" ARE EXPECTED WITH ISOLATED HIGHER AMOUNTS POSSIBLE THROUGH
08Z. 

FLASH FLOODING IS POSSIBLE ACROSS THE OUTLINED AREA WITH HIGHEST
RISK PRIMARILY NORTH OF THE SURFACE BOUNDARY WHERE FFG VALUES WERE
AS LOW AS 0.50 TO 1.00 INCHES PER HOUR.  

BANN

ATTN...WFO...ILN...ILX...IND...LMK...LSX...MEG...OHX...PAH...

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

LAT...LON   39538597 39418504 39068417 38578400 38098506 
            37578534 37088559 36088710 35888871 36988856 
            37818934 38648891 39278769