MESOSCALE PRECIPITATION DISCUSSION 0106
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
632 PM EDT SAT JUN 07 2014
AREAS AFFECTED...EASTERN IA...NORTHWEST IL...SOUTHWEST WI
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE
VALID 072230Z - 080145Z
SUMMARY...SLOW-MOVING HEAVY SHOWERS AND A FEW THUNDERSTORMS WILL
FOSTER SOME ADDITIONAL THREAT FOR FLASH FLOODING OVER THE NEXT FEW
HOURS.
DISCUSSION...THE LATEST IR SAT IMAGERY SHOWS A WELL-DEFINED LOW
AND MID LVL LOW CENTER CROSSING NERN MO AND MOVING INTO CNTRL IL
LATE THIS AFTERNOON. THE ENERGY IS INTERACTING WITH A MOIST AND
MODESTLY UNSTABLE FEED OF AIR THAT IS ADVANCING NEWD AROUND THE
SRN FLANK OF THE LOW CENTER AND THEN BACK NW AROUND THE NRN FLANK
OF THE SYS INTO A FAIRLY ROBUST DEFORMATION ZONE THAT IS SITUATED
OVER ERN IA...NWRN IL AND MOVING INTO SWRN WI.
MEANWHILE...THERE IS A FRONTAL ZONE SETTLING SWD FROM THE UPR
MIDWEST AND SO THERE IS AN AXIS OF RATHER ENHANCED LOW LVL
CONVERGENCE AROUND THE NRN FLANK OF THE DEEPER LYR LOW CENTER. THE
LATEST RAP ANALYSIS CONTINUES TO SHOW VERY MODEST
INSTABILITY...WITH MUCAPE VALUES AROUND 500 J/KG TO 750 J/KG FROM
ERN IA NEWD INTO CNTRL WI AND GENERALLY FOCUSED ALONG THE FRONT.
HOWEVER...THE LATEST RAP ANALYSIS DOES SHOW A NOTABLE AXIS OF
STRONGER FRONTOGENETICAL FORCING ONGOING IN THE 850MB TO 700MB
LAYER ACROSS ESP ERN IA THROUGH FAR NWRN IL AND INTO SWRN WI.
THIS COINCIDES WITH A DYNAMICALLY FAVORABLE MID LVL DEFORMATION
AXIS AND COUPLED WITH LOW TO MID LVL MOISTURE TRANSPORT IS HELPING
TO GENERATE AND SUSTAIN A FAIRLY LARGER AREA OF HEAVY SHOWERS WITH
SOME EMBEDDED THUNDERSTORMS. CLOUD TOPS REMAIN FAIRLY WARM
SUGGESTING EFFICIENT RAINFALL PRODUCING CELLS. ALREADY OBSERVED
RAINFALL RATES OF UP TO 2 INCHES/HR HAVE OCCURRED.
OVER THE NEXT FEW HOURS...EXPECT THE THREAT FOR A FAIRLY NARROW
AXIS OF HVY TO POTENTIALLY EXCESSIVE RAINS FROM ERN IA NEWD INTO
SWRN WI. GIVEN THE RAINFALL RATES...FLASH FLOODING WILL BE
POSSIBLE. WILL CONTINUE TO MONITOR.
ORRISON
ATTN...WFO...GRB...LOT...ILX...MKX...DVN...ARX...DMX...
ATTN...RFC...NCRFC...OHRFC...
LAT...LON 40639103 40899190 41519238 42139224 43089088 44078947
44588825 44148793 43578825 42278898 41018998 40639103
Last Updated: 632 PM EDT SAT JUN 07 2014