000
FXUS63 KMPX 141821
AFDMPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
121 PM CDT FRI JUN 14 2013

.UPDATE...

18Z AVIATION DISCUSSION ADDED BELOW.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 403 AM CDT FRI JUN 14 2013

LARGE 50H RIDGE WILL FLATTEN OUT AS A COLD FRONTAL BOUNDARY
MAKES ITS WAY INTO THE EASTERN DAKOTAS BY THIS AFTERNOON.
CURRENTLY 0.5 DEGREE REFLECTIVITY INDICATING SHOWERS AND
ISOLATED THUNDERSTORMS STRETCHING FROM REDWOOD FALLS SOUTHEAST
INTO NORTH CENTRAL IA. USED GFS40 310K ISENTROPIC SURF ANALY
TO PROG PROGRESSION AND INTENSITY OF CONVECTION THROUGH
SATURDAY NIGHT. WARM FRONTAL BOUNDARY ACTIVITY SHOULD REMAIN
MAINLY SHOWERS WITH EMBEDDED T-STORMS INTO AT LEAST THE
EARLY AFTN. ALTHOUGH 850MB LI`S DECREASE MARKEDLY BY 15/06Z
...PRETTY FORMIDABLE 700MB CAP BUILDS OVER MUCH OF SW AND
SOUTH CENTRAL MN DURING THE EVENING HOURS. ANTICIPATE CAP
TO BE PUNCTURED OVER SOUTH CENTRAL MN BY EARLY THIS EVENING.
MOISTURE TRANSPORT OVER MUCH OF MN CWA BEGINS TO RAMP UP
BY MID AFTERNOON AND CONTINUES INTO 15/03Z OVER MUCH OF
THIS REGION...THEN SHIFTS TO SOUTH CENTRAL MN INTO WEST
CENTRAL WI INTO 15/09Z TIME PERIOD. VERY STRONG 35 TO 40KT
850MB LOW LEVEL JET NOTED OVER MUCH OF SOUTHERN THIRD
OF MN FROM 15/00-03Z. SATURATED TO SOMEWHAT SATURATED
GROUND OVER FARIBAULT AND FREEBORN COUNTIES ORIGINATING FROM
2 TO 4 INCHES OF RAINFALL ON WEDNESDAY NIGHT HAS PROMPTED THE
ISSUANCE OF A FLASH FLOOD WATCH FOR THESE COUNTIES LATE THIS
AFTERNOON INTO EARLY SATURDAY EVENING. ALTHOUGH CONFIDENCE IN
SIGNIFICANT FLOODING IS NOT HIGH...PRESENCE OF SLOW MOVING COLD
FRIDAY NIGHT INTO SATURDAY AFTERNOON...COULD GENERATE A PERIOD OF
TRAINING SHOWERS AND THUNDERSTORMS OVER PORTIONS OF THESE COUNTIES.
HOWEVER ...STILL EXPECT BRUNT OF ANY SIGNIFICANT MOISTURE TO FALL
OVER NORTHERN AND CENTRAL IOWA...AND PORTIONS OF SE MN. WITH
THAT SAID...AREA OF MN FLOOD POTENTIAL COULD OBSERVE BETWEEN
ONE AND TWO INCHES OF RAINFALL UNDER HEAVIEST T-STORM ACTIVITY.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 403 AM CDT FRI JUN 14 2013

NOCTURNAL COMPLEX OF SHOWERS AND THUNDERSTORMS SHOULD WANE A BIT
ON SATURDAY MORNING AS MOISTURE TRANSPORT VEERS OFF IN TYPICAL
WARM SEASON FASHION...BUT EXPECT STORM REIGNITION BY SATURDAY
AFTERNOON AS A SURFACE COLD FRONT PASSES ACROSS THE FORECAST AREA.
BOTH NAM AND GFS MODELS DEPICT DECENT DESTABILIZATION BY 18Z FROM
SOUTH CENTRAL MN INTO CENTRAL WI ALONG/AHEAD OF THE FRONT. WHILE
THE FRONT SHOULD EXIT THE FORECAST AREA PRIOR TO
STALLING...THUNDERSTORMS COULD QUICKLY PRODUCE A QUICK 1 TO 2 INCH
BURST OF HEAVY RAINFALL...GIVEN FORECAST PWATS OF 1.5 TO 2 INCHES
STRADDLING THE MN/IA BORDER. HAVE THEREFORE MAINTAINED THE FLASH
FLOOD WATCH UNTIL 00Z SUNDAY.

PRECIPITATION SHOULD MOVE OFF STEADILY ON SATURDAY EVENING WITH
THE DEPARTURE OF THE FRONT AND ACCOMPANYING SHORTWAVE. SUNDAY
SHOULD BE A FAIRLY BENIGN AND SEASONAL DAY...IN BETWEEN THE
DEPARTING SYSTEM AND AN ADVANCING STACKED CANADIAN LOW PRESSURE
SYSTEM. THIS FEATURE ARRIVES SUNDAY NIGHT AND MONDAY...AND BRINGS
ANOTHER WINDOW OF SHOWERS AND THUNDERSTORMS.

BROAD HIGH PRESSURE EXPANDS ACROSS THE NORTH CENTRAL CONUS ON MONDAY
NIGHT THROUGH THE MIDDLE OF NEXT WEEK...AS WESTERN TROUGHING
FOSTERS MID LEVEL RIDGING DOWNSTREAM OVER THE NORTH CENTRAL CONUS.
THIS SHOULD FACILITATE DRY AND WARM WEATHER FOR THE AREA.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 121 PM CDT FRI JUN 14 2013

LOW CONFIDENCE TAF PACKAGE HERE...AS MANY OF THE HI-RES MODELS SHOW
STORMS LACKING ACROSS THE MPX AREA FOR MUCH OF THE EVENING. LINE
OF STORMS CURRENTLY NEAR KSUX HAS DEVELOPED ON LEADING EDGE OF
700MB CAP...AND EXPECT THIS ACTIVITY TO FOLLOW THICKNESS LINES AND
MUCAPE GRADIENT AND HEAD SE THROUGH IA...AS THE 12Z NCAR ARW WRF
SHOWS. FOR THE MPX AREA...CURRENT THINKING IS WE WILL HAVE TO WAIT
FOR CONVECTION ON THE COLD FRONT TO GET HERE. EXPECT STORMS TO
INITIATE IN THE ERN DAKOTAS ALONG THE FRONT AROUND 21Z...THEN PUSH
INTO WRN MN AROUND 00Z. AS A RESULT...DELAYED TSRA TIMING BY AN
HOUR OR TWO IN TAFS. EXPECT HIGHEST COVERAGE OF STORMS TO BE FROM
MKT/STC ON EAST...AS BETTER LLJ SUPPORT ARRIVES AFTER 06Z...PER
THE RAP. THIS SHOULD RESULT IN A BKN LINE OF STORMS THAT MOVES
ACROSS ERN MN/WRN WI LATE TONIGHT. ALSO SEEING INDICATIONS OF
INCREASED LOW LEVEL MOISTURE IN THE WAKE OF THE FRONT...WITH THE
NAM/GFS/RAP ALL WANTING TO DEVELOP MVFR OR LOWER CIGS TONIGHT AS
WELL. CONFIDENCE NOT VERY HIGH AT THE MOMENT ON THE CIG FORECAST
AS IT WILL BE DEPENDENT ON HOW CONVECTION EVOLVES TONIGHT.

KMSP...MAIN CHANGES WITH THE TAF WERE TO SLIGHTLY DELAY ARRIVAL OF
TS AND HOLD ON TO THE SE WINDS A BIT LONGER BEFORE RAPIDLY VEERING
THEM TOWARD THE NW AFTER 9Z. THOUGH CCFP HAS HIGH CONFIDENCE/LOW
COVERAGE AREA OF THUNDER WEST OF MSP BY 01Z...CURRENTLY THINK THAT
IS OVERDONE...THIS IS DUE TO THE PRESENCE OF WARMING TEMPERATURES
AT 700 AND THE RESULTANT INCREASE IN CAPPING EXPECTED. AT THE
MOMENT...IF A PREFERRED MODEL WERE TO BE PICKED...THE ARW EAST
WOULD GET MY VOTE...WHICH SHOWS A BKN LINE OF STORMS MOVING ACROSS
ERN MN BETWEEN 5 AND 9Z. THIS SCENARIO IS ALSO PLAYED OUT BY
MEMBERS 1/3/4 OF THE HOPWRF.

/OUTLOOK FOR KMSP/
SUN...VFR. WSW WINDS 5-10KTS.
MON...CHANCE OF MVFR CONDS AND TSRA. NW WINDS 10KTS.
TUE...VFR. WINDS LGT AND VRB.

&&

.HYDROLOGY...
ISSUED AT 403 AM CDT FRI JUN 14 2013

ISSUED FLOOD WATCH OVER SMALL PORTION OF SOUTH CENTRAL MN FROM LATE
THIS AFTN INTO EARLY SATURDAY EVENING DUE ACCUMULATION OF TWO TO
FOUR INCH SWATH OF RAINFALL OVER PORTIONS OF FARIBAULT AND FREEBORN
COUNTIES ON WEDNESDAY NIGHT...AND POTENTIAL FOR TRAINING SHOWERS
AND THUNDERSTORMS LATE THIS AFTERNOON AND INTO SATURDAY. THE
POTENTIAL EXISTS FOR ANOTHER ONE TO TWO INCHES OF RAINFALL OVER
THESE COUNTIES...WITH SOMEWHAT HIGHER LOCAL AMOUNTS ALSO POSSIBLE.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...FLASH FLOOD WATCH FROM 4 PM CDT THIS AFTERNOON THROUGH SATURDAY
     EVENING FOR MNZ092-093.

WI...NONE.
&&

$$

SHORT TERM...AJZ
LONG TERM...LS
AVIATION...MPG
HYDROLOGY...AJZ