MESOSCALE PRECIPITATION DISCUSSION 0075
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
220 AM EDT TUE MAY 28 2013
 
AREAS AFFECTED...CENTRAL AND EASTERN IA...NORTHEAST MO...WESTERN
IL 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 280620Z - 280930Z
 
SUMMARY...FORWARD PROPAGATING MCS PRODUCING INTENSE RAINFALL RATES
OVER SATURATED SOILS. ADDITIONAL SHORT-TERM FLASH FLOODING WILL BE
POSSIBLE.

DISCUSSION...LATEST RADAR AND IR SAT IMAGERY SHOWS A COLD-TOPPED
FORWARD PROPAGATING MCS ADVANCING ACROSS SWRN IA ATTM...WITH THE
SRN TAIL OF IT SEEN BOWING RATHER RAPIDLY EASTWARD ACROSS NRN MO.
ENHANCING THE CONVECTIVE SUSTAINABILITY OF THIS COMPLEX IS THE
PRESENCE OF A 50 TO 60 KT SWLY LOW LEVEL JET AS PER LATEST RAP
ANALYSIS...WITH THE NOSE OF IT AIMED INTO THE SRN FLANK OF THE
MCS. CLOUD TOPS OVER THE LAST COUPLE OF HOURS HAVE CONTINUE TO
COOL...SUGGESTING MORE VIGOROUS CONVECTIVE GROWTH...AND THUS AN
INCREASE IN RAINFALL RATES AT LEAST LOCALLY. IT IS LIKELY THAT THE
CORE OF THIS CONVECTIVE COMPLEX WILL TRAVERSE THE REMAINDER OF
CNTRL/ERN IA OVER THE NEXT FEW HOURS AND MOVE INTO WRN IL. THE SRN
TAIL OF THE MCS SHOULD CROSS THE REMAINDER OF NERN MO BEFORE
EVENTUALLY REACHING IL. GIVEN WET ANTECEDENT CONDITIONS...AND
RAINFALL RATES UPWARDS OF 1.5 INCHES/HR...EXPECT THERE TO BE SOME
ADDITIONAL FLASH FLOOD CONCERNS.

ORRISON


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

LAT...LON   40228995 39869058 39529116 39309221 39289317 39359351
            39629393 39929384 40379385 40909404 41419435 41759490
            42169501 42509483 42609394 42459237 42429141 42458968
            42138867 41558838 41108876 40758946 40228995