MESOSCALE PRECIPITATION DISCUSSION 0304
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1148 AM EDT SAT JUN 16 2018

AREAS AFFECTED...SOUTHERN U.P. OF MI...EXT NORTHEAST WI...

CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE

VALID 161550Z - 162145Z

SUMMARY...SLOW MOVING/UPSTREAM REGENERATIVE COMPLEX POSE FLASH
FLOOD RISK OVER NEXT FEW HOURS.

DISCUSSION...GOES-16 VISIBLE AND 10.3UM IR CHANNELS DEPICT RECENT
UPTICK IN CONVECTIVE VIGOR WITH NUMEROUS OVERSHOOTING TOPS AND
GENERAL COOLING AND EXPANSION OF THE CLOUD SHIELD OVER GREEN
BAY/NORTHERN LAKE MICHIGAN AND ACROSS LOWER MENOMINEE RIVER
VALLEY.  THREE CHANNEL WV SUITE AND VWP AT MQT/DLH DENOTE
SHORTWAVE ENERGY LIFTING NORTHEAST WEST OF THE AREA OF CONCERN. 
YET 850 TO 7H FLOW CONTINUES TO BE SUPPORTIVE OF WAA TO MAINTAIN
CONVECTIVE DEVELOPMENT AND STARTING TO ALIGN WITH THE MEAN CELL
MOTIONS TO SUPPORT BACKBUILDING AND TRAINING OF CELLS. WELL OF
INSTABILITY REMAINS AS RAP ANALYSIS DEPICTS LARGE AREA OF 1000
J/KG MUCAPES AVAILABLE TO BE TAPPED BY THE LOW LEVEL
CONVERGENCE/WAA.  ADDITIONALLY...AMPLE DEEP LAYERED MOISTURE/FLUX
WILL ALLOW FOR HIGH RAINFALL EFFICIENCY AS TPWS IN THE 1.75-2"
RANGE WILL SUPPORT EQUALLY HIGH RAIN FALL RATES.   A LIMITING
QUESTION THOUGH REMAINS ON LENGTH OF DURATION AS THE MAIN FORCING
PASSES TOWARD 16-18Z REDUCING THE LLJ STRENGTH AND REDUCING BEST
ORIENTATION FOR TRAINING.  THIS AS BEEN SEEN RECENTLY BY THE SHIFT
IN FOCUS FROM THE BACKBUILDING THAT WAS OVER LAKE MICHIGAN BACK
WEST TO THE CURRENT AREA OF CONCERN. RAP ANALYSIS 500-1000MB
THICKNESS FIELDS SUGGEST A SMALL SOUTHWARD SHIFT/PROPAGATION IS
POSSIBLE TOWARD SOUTHERN GREEN BAY...WHICH MAY STAVE OFF VERY HIGH
RAINFALL TOTALS HOWEVER THE POTENTIAL FOR 2-3" RAINFALL TOTALS IS
SUFFICIENT TO CONSIDER FLASH FLOODING POSSIBLE IN THE NEXT FEW
HOURS.  CONFIDENCE IS BOLSTERED A BIT BY RECENT OPERATIONAL HRRR
RUNS THAT SUPPORT THIS SCENARIO UNFOLDING. 

GALLINA

ATTN...WFO...GRB...MQT...

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

LAT...LON   46048778 45658677 45348674 44888712 44638734
            44688763 45108816 45538833 45968830