MESOSCALE PRECIPITATION DISCUSSION 0192
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
124 PM EDT THU JUN 11 2015
 
AREAS AFFECTED...PORTIONS OF THE MIDWEST 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 111724Z - 112324Z
 
SUMMARY...CIN IS BEGINNING TO ERODE NEAR A SURFACE BOUNDARY DRAPED
ACROSS THE AREA.  CONSIDERING SATURATED SOILS, FLASH FLOODING IS
POSSIBLE IN THIS REGION.

DISCUSSION...A COMPOSITE BOUNDARY (PART OUTFLOW BOUNDARY, PART
STATIONARY FRONT) EXTENDS ROUGHLY ALONG THE 40TH PARALLEL ACROSS
THE MIDWEST AHEAD OF A SURFACE WAVE LOCATED NEAR GID.  POCKETS OF
1000 J/KG ML CAPE HAVE BEGUN TO DEVELOP NEAR THE NE/KS BORDER,
WEST-CENTRAL IL, AND NORTHERN IN.  INFLOW AT 850 HPA OF 25-40 KTS
IS SEEN ON VAD WIND PROFILES ACROSS KS, MO, AND IA -- NEAR THE
MAGNITUDE OF THE 850-400 HPA MEAN WIND.  CIN HAS BEGUN TO ERODE
ACROSS THE REGION PER THE SPC MESOANALYSIS.  PRECIPITABLE WATER
VALUES OF 1.5-2" LIE ACROSS THE MIDWEST PER GFS INFORMATION.

THE EXPECTATION IS FOR THE SURFACE BOUNDARY TO BECOME THE FOCUS
FOR CONVECTION THIS AFTERNOON.  A COMBINATION OF THE 1000-500 HPA
THICKNESS PATTERN AND FORWARD PROPAGATING CORFIDI VECTORS SUGGEST
ORGANIZED CONVECTION COULD MOVE JUST NORTH OF DUE EAST AT ~25 KTS.
 WHILE CELL TRAINING IS EXPECTED TO BE THE MAIN THREAT, SOME
BACKBUILDING ELEMENTS ARE POSSIBLE, PARTICULARLY ACROSS NORTHERN
IL WHERE 850 HPA INFLOW IS ON THE INCREASE.  SURFACE FLOW FROM
LAKE MICHIGAN SHOULD INCREASE THE STRENGTH OF THE BAROCLINIC ZONE
IN NORTHEAST IL, WITH CLOUD COVER ALSO INCREASING THERMAL
GRADIENTS LATER TODAY.  THE MESOSCALE GUIDANCE SHOWS SPREAD, BUT
AGREES THAT LOCAL AMOUNTS OF 2-3" ARE POSSIBLE OVER THE NEXT
SEVERAL HOURS.  SINCE AVAILABLE MOISTURE SUPPORTS CONVECTION WITH
HOURLY RAIN RATES UP TO 2", THIS RAINFALL COULD OCCUR QUICKLY. 
THE 06Z SSEO NEIGHBORHOOD PROBABILITIES SHOW THAT THREE HOUR FLASH
FLOOD GUIDANCE VALUES COULD BEGIN TO BE EXCEEDED AFTER 21Z ACROSS
PORTIONS OF IA.  FLASH FLOODING IS POSSIBLE, PARTICULARLY ACROSS
SOUTHEAST NE, SOUTHWEST IA, AND NORTH-CENTRAL IL WHERE SOILS ARE
SATURATED FROM RECENT RAINFALL.   

ROTH

ATTN...WFO...ARX...DMX...DVN...EAX...GID...ILX...LOT...LSX...
TOP...

ATTN...RFC...MBRFC...NCRFC...

LAT...LON   42858918 42808778 42188765 41938756 41788749 
            41658748 41108757 40898912 40409119 39929251 
            39029471 39319608 39779707 40639761 41599685 
            42279479 42759114