MESOSCALE PRECIPITATION DISCUSSION 0194
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
713 PM EDT THU JUN 11 2015
 
AREAS AFFECTED...NORTHEAST KS...CENTRAL AND SOUTHERN IA...NORTHERN
MO...NORTHERN IL...EXTREME SOUTHERN WI 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 112312Z - 120500Z
 
SUMMARY...ADDITIONAL HEAVY SHOWERS AND THUNDERSTORMS WILL PRODUCE
LOCALLY VERY HEAVY RAINFALL OVER THE NEXT SEVERAL HOURS. FLASH
FLOODING IS POSSIBLE.

DISCUSSION...LATE-DAY 1-MIN GOES-14 SRSO IMAGERY SHOWS AN
ORGANIZING AXIS OF HEAVY SHOWERS AND THUNDERSTORMS DEVELOPING
ALONG AND OUT AHEAD OF AN AREA OF LOW PRESSURE MOVING EAST ALONG
THE IA/MO BORDER. THIS LOW PRESSURE WAVE IS ASSOCIATED WITH A
WELL-DEFINED SHORTWAVE TROUGH THAT IS MOVING INTO THE
MIDWEST...AND OVER THE NEXT SEVERAL HOURS...CONVECTION IS EXPECTED
TO INCREASE IN COVERAGE AS THE SHORTWAVE ENERGY INTERACTS WITH AN
ENHANCING POOL OF RELATIVELY DEEP MOISTURE AND INSTABILITY.

HI RES MODEL OUTPUT INCLUDING THE 12Z ARW/NMMB AND 22Z HRRR
FORECAST AN INCREASE IN THE S/SWLY LOW LEVEL JET OVER THE NEXT FEW
HOURS...AND THIS WILL ENHANCE THE THERMODYNAMIC ENVIRONMENT FOR
CONVECTION TO EXPAND IN COVERAGE AND INTENSIFY. THE LATEST
GOES-SOUNDER IMAGERY ALREADY DEPICTS A POOL OF 1.5 TO 1.75 INCH
PWATS ACROSS MUCH OF THE LOWER MO VALLEY WHICH WILL ENHANCE THE
RAINFALL RATES. MEANWHILE...THE LOW TO MID LEVEL STEERING FLOW IS
FORECAST TO BECOME ORIENTED MORE PARALLEL TO THE FRONT...WHICH IS
EXPECTED TO ENHANCE THE POTENTIAL FOR TRAINING CONVECTION.
THEREFORE...SOME VERY HEAVY RAINFALL TOTALS ARE EXPECTED WITH SOME
AMOUNTS POTENTIALLY EXCEEDING 5 INCHES THROUGH LATE EVENING. THIS
COUPLED WITH SOME OF THE RECENT HEAVY RAINFALL SEEN SHOULD ENHANCE
THE THREAT FOR FLASH FLOODING.

ORRISON

ATTN...WFO...ARX...DMX...DVN...EAX...ILX...LOT...LSX...MKX...

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

LAT...LON   42828976 42718832 42178750 41168769 40578857 
            40218979 39869119 39559266 39269423 39159500 
            39229552 39579572 40519526 41599483 42169372 
            42599189 
!