MESOSCALE PRECIPITATION DISCUSSION 0543
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
231 AM EDT THU AUG 11 2016
 
AREAS AFFECTED...FAR SOUTHEASTERN SD/SOUTHERN MN/WESTERN
WI/NORTHWESTERN IA... 
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE 
 
VALID 110631Z - 111101Z
 
SUMMARY...WEAKENING WEST-EAST ORIENTED OUTFLOW ACROSS SOUTHERN MN
HAS FEATURED A DECAYING BAND OF QUASI-STATIONARY THUNDERSTORMS.
WHILE RAINFALL RATES HAVE COME DOWN WITH THIS LINE...AN UPSTREAM
WAVY CONVECTIVE LINE SHOULD LEAD TO AN INCREASE IN CELL MERGERS
AND PERHAPS LOCALIZED TRAINING DURING THE NEXT 3 TO 4 HOURS. AREAS
HIT EARLIER TONIGHT ARE MOST SUSCEPTIBLE TO FLASH FLOODING GIVEN
THE SATURATED SOILS.

DISCUSSION...EARLY THIS MORNING...IR SATELLITE IMAGERY ACROSS THE
UPPER MIDWEST SHOWED THE REMNANTS OF AN OUTFLOW BOUNDARY EXTENDING
OVER SOUTHERN MN. ITS SOUTHWARD PROGRESSION HAS HALTED WHILE
REMAINING QUASI-STATIONARY IN ADVANCE OF A NORTH-SOUTH LINE OF
THUNDERSTORMS CURRENTLY CROSSING THE SD/MN BORDER. THE GOES-14
SUPER RAPID SCAN SATELLITE IMAGERY DEPICTED THE COLDEST CLOUD TOPS
ACROSS EAST-CENTRAL SD WITH TEMPERATURES IN THE -70 TO -75C RANGE.
RECENT LIGHTNING DATA INDICATED THIS SYSTEM STILL CONTAINED STRONG
UPDRAFTS PER THE LARGE AMOUNT OF STRIKES OBSERVED IN THE NLDN. AS
THIS COMPLEX ADVANCES INTO SOUTHWESTERN MN...EXPECT AN ENHANCEMENT
IN THE FLASH FLOOD THREAT GIVEN THE INCREASE IN CELL MERGERS AND
PERHAPS SOME LOCALIZED AREAS OF TRAINING. WHILE THE COMPLEX IS NOT
NEARLY AS ORGANIZED AS EARLIER IN THE NIGHT...STRONG LOW-LEVEL JET
DYNAMICS COUPLED WITH ENOUGH LINGERING ELEVATED INSTABILITY SHOULD
HELP KEEP THE SYSTEM GOING THROUGH AT LEAST 12Z.

AMONG THE RECENT CAMS...FEEL MANY OF THEM ARE TOO FAR NORTH
RELATIVE TO CURRENT RADAR/SATELLITE TRENDS. IT APPEARS THE 05Z
OPERATIONAL HRRR AND 00Z HRW-ARW DEPICT A REASONABLE SCENARIO
FAVORING THE HEAVIEST AMOUNTS ACROSS THE SOUTHERN THIRD OF MN.  


RUBIN-OSTER

ATTN...WFO...ABR...ARX...DLH...DMX...FSD...GRB...MPX...OAX...

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

LAT...LON   46189240 45409061 44199009 43809047 43659167 
            43589316 42709524 42599708 43039767 44569658 
            45999475