MESOSCALE PRECIPITATION DISCUSSION 0052
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
942 PM EDT SUN MAY 19 2013
 
AREAS AFFECTED...NORTHERN MO...CENTRAL AND EASTERM IA...SOUTHEAST
MN...WESTERN WI 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 200142Z - 200530Z
 
SUMMARY...POTENTIAL CONTINUES FOR CONVECTIVE CLUSTERS TO MERGE AND
LOCALLY TRAIN OVER THE SAME AREA THE NEXT FEW HOURS AS A BROKEN
QLCS SLOWLY SHIFTS EAST.

DISCUSSION...NUMEROUS COLD-TOPPED CONVECTIVE CLUSTERS CONTINUE
INUNDATE THE MIDWEST ATTM...AS WHAT ESSENTIALLY CONSTITUES A QLCS
ADVANCES SLOWLY EAST WITH THE AID OF A WELL-DEFINED MCV OVER NWRN
MO. EXTENDING NORTHEAST OF THE MCV IS A WELL-DEFINED CONVECTIVELY
REINFORCED OUTFLOW BOUNDARY...WITH POCKETS OF BOWING ACTIVITY
ASSOCIATED WITH STRONGER CONVECTION. VERY UNSTABLE AIR REMAINS
POOLED CURRENTLY OVER NERN MO...SERN IA AND WRN IL...WHICH IS
BEING AIDED BY A ROBUST SRLY LOW LEVEL JET. LATEST GOES-SOUNDER
LI/S ARE ON THE ORDER OF -10 OVER PORTIONS OF THIS AREA. MEAN
LAYER FLOW REMAINS SWLY OVER THE OUTFLOW BOUNDARY...AND THIS
COUPLED WITH THE LOW LEVEL JET REACHING UPWARDS OF 40 TO 50 KTS IS
HELPING TO MITIGATE THE EASTWARD ADVANCE OF THE QLCS. RAINFALL
RATES OF 2 TO 2.5 INCHES/HR ARE EXPECTED...AND THIS COUPLED WITH
POCKETS OF TRAINING AND REPEAT CONVECTION WILL SUSTAIN A FLASH
FLOOD THREAT FOR AT LEAST THE NEXT 3 TO 4 HOURS. WILL CONTINUE TO
MONITOR.

ORRISON


ATTN...WFO...GRB...MKX...DVN...DLH...ARX...MPX...DMX...EAX...

LAT...LON   41609120 40989175 40129288 39889386 40049424 40589446
            41059416 42079337 43479300 45669158 45429006 42919037
            41609120 


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