MESOSCALE PRECIPITATION DISCUSSION 0315
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
504 PM EDT SUN JUN 11 2017

AREAS AFFECTED...CNTRL MN INTO NRN WI

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

VALID 112102Z - 120130Z

SUMMARY...TRAINING RAINFALL IS EXPECTED TO CONTINUE OVER PORTIONS
OF NWRN WI AND PERHAPS FAR ERN MN OVER THE NEXT 3-4 HOURS.
RAINFALL RATES OF 1-2 IN/HR COULD LEAD TO 2-4 INCHES OF RAIN BY
01Z...WITH RATES IN EXCESS OF FLASH FLOOD GUIDANCE.

DISCUSSION...RADAR TRENDS OVER THE PAST HOUR FROM KDLH SHOWED 2-3
NARROW AXES OF TRAINING RAINFALL ORIENTED FROM WSW TO ENE OVER
NWRN WI. RAP ANALYSIS SOUNDINGS SHOW THE ACTIVITY IS
ELEVATED...ROOTED NEAR 700 MB...AND IN AN ENVIRONMENT
CHARACTERIZED BY 1000-2000 J/KG MUCAPE. THE SPC MESOANALYSIS
SHOWED SIMILAR CAPE VALUES AND PRECIPITABLE WATER VALUES OF 1.7 TO
1.8 INCHES...CONFIRMED BY A GPS REPORT FROM NEAR SIOUX FALLS OF
1.7 INCHES AT 19Z. THE THUNDERSTORMS ARE OCCURRING VIA OVERRUNNING
OF A QUASI-STATIONARY FRONT LOCATED IN FAR SRN MN...OUT AHEAD OF A
POSITIVELY TILTED 700 MB SHORTWAVE LOCATED FROM FAR WRN MN INTO
ERN SD AT 20Z...FORECAST TO ADVANCE ENEWD OVER THE NEXT 3-6 HOURS.

THE VAD WIND PLOT FROM KMPX HAS SHOWN 45-55 KT AT 700 MB OVER THE
PAST HOUR FROM THE SW...AHEAD OF THE SHORTWAVE MOVING EAST FROM
SD. WHILE SOME WEAKENING OF 700 MB FLOW IS FORECAST BY THE
RAP...CONTINUED ROBUST MOISTURE TRANSPORT NEAR 700 MB IS EXPECTED
TO PROLONG TRAINING ECHOES OVER NWRN WI WITH ADDITIONAL
THUNDERSTORM DEVELOPMENT NOTED AHEAD OF THE SHORTWAVE OVER CNTRL
MN AS OF 2030Z. COVERAGE AND INTENSITY OF CONVECTION OVER CNTRL MN
IS EXPECTED TO INCREASE OVER THE NEXT HOUR OR TWO WHILE
TRANSLATING EWD INTO NWRN WI. THE COMBINATION OF ONGOING TRAINING
AND ADDITIONAL RAINFALL TO APPROACH FROM THE WEST MAY CAUSE FLASH
FLOODING IN A FEW LOCATIONS GIVEN FLASH FLOOD GUIDANCE OF 2-3
INCHES IN 3 HOURS AND WET ANTECEDENT GROUNDS DUE TO RAINFALL FROM
EARLIER THIS MORNING OF UP TO AN INCH OR SO. BY 01Z...HEAVY
RAINFALL OVER NWRN WI SHOULD BEGIN TO ADVANCE SEWD AS THE TROUGH
AXIS MOVES THROUGH THE REGION...BUT TRENDS WILL CONTINUE TO BE
MONITORED.

OTTO

ATTN...WFO...ARX...DLH...GRB...MPX...MQT...

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

LAT...LON   46569101 46428957 45768920 45298961 44869065
            45049289 45069415 45269455 45709439 46219317
            46509212