MESOSCALE PRECIPITATION DISCUSSION 0073
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
430 AM EDT MON MAY 27 2013
 
AREAS AFFECTED...NORTHWEST THROUGH SOUTH-CENTRAL IA 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 270830Z - 271130Z
 
SUMMARY...FORWARD PROPAGATING MCS PRODUCING INTENSE SHORT-TERM
RAINFALL RATES OF 1 TO 1.5 INCHES/HR. WILL BE MOVING OVER LOCALLY
SATURATED SOILS...AND SUPPORTING ADDITIONAL SHORT-TERM FLASH FLOOD
CONCERNS.


DISCUSSION...A STRONG MCS MOVING ACROSS FAR ERN NEB AND WRN IA
ATTM WILL CONTINUE TO ADVANCE GENERALLY SEWD OVER THE NEXT 2 TO 3
HOURS...ALTHOUGH THE NEB PORTION WILL BE TENDING TO BOW MORE SSEWD
AND REACHING NERN KS AND NWRN MO OVER THE NEXT HOUR OR SO AS IT
INTERACTS WITH THE LEADING EDGE OF GREATER INSTABILITY OVER THE
CNTRL PLAINS AND THE NOSE OF THE LOW LEVEL JET.  THE NRN PORTION
OF THE LINE TO THE WEST OF DSM IS PRODUCING VERY INTENSE RAINFALL
RATES...ON THE ORDER OF 1 TO 1.5 INCHES/HR...BUT WITH MOST OF THIS
OCCURRING IN ABOUT 15 TO 30 MINUTES. THIS PORTION OF THE MCS IS
ELEVATED...BUT IS BEING SUSTAINED BY MUCAPE VALUES OF 1000 TO 1500
J/KG. OVER THE NEXT FEW HOURS THIS PORTION OF THE LINE WILL BE
ENCOUNTERING GREATER STABILITY AS IT MOVES TWD SERN IA...AND SO
THERE SHOULD BE A WEAKENING TREND NOT LONG AFTER SUNRISE.
NEVERTHELESS...EXPECT THE SHORT-TERM RAINFALL RATES TO BE
SUFFICIENT TO WARRANT SOME ADDITIONAL FLASH FLOOD POTENTIAL AND
ESPECIALLY GIVEN LOCALLY SATURATED SOILS FROM EARLIER RAINFALL.

ORRISON


ATTN...WFO...DVN...DMX...FSD...OAX...

LAT...LON   42039313 43099465 43299570 43109635 42329648 41609595
            41169545 40899490 40699410 40649313 40729272 40929239
            41239237 42039313