National Weather Service Weather Forecast Office

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

000
FXUS63 KMPX 141104
AFDMPX

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

.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 SATRUDAY 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 SIGNFICANT 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 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 547 AM CDT FRI JUN 14 2013

LIGHT SHOWER ACTIVITY FROM NEAR KAXN TO KAEL WILL CONTINUE
TO DECREASE IN INTENSITY AND COVERAGE AS DIVERGENCE ALOFT
BECOMES STRONGER BY LATE THIS MORNING. WARM FRONT EMANATING
FROM SFC CYCLONE OVER CENTRAL GREAT PLAINS WILL BE TRIGGER
FOR SCT MAINLY LIGHT SHOWERS THIS AFTN OVER MUCH OF AVIATION
REGION. VFR CIGS AND VSBYS WILL DEGRADE TO MVFR WITH MUCH
MORE WIDESPREAD CONVECTION COMMENCING BY LATE THIS AFTN
OVER MUCH OF MN AIRPORT REGION...AND THEN INTO WEST CENTRAL
WI BY THE EARLY EVENING HOURS. VSBYS WILL BE DEGRADED BY
SHOWER ACTIVITY BUT CIGS WILL DETIORATE INTO LOW END MVFR
RANGE MOST SITES BY LATE IN THE PERIOD. WEAK SE FLOW WILL
STRENGTHEN BY LATE THIS MORNING...AND WEAKEN WITH DECOUPLING
BY 23Z. COULD BE A PROBLEM THIS EVENING WITH SPEED SHEAR
AS POTENT SOUTHERLY 850MB JET DEVELOPS.

KMSP...

/OUTLOOK FOR KMSP/

VFR CIGS AND VSBYS THROUGH MUCH OF FIRST HALF OF TAF PERIOD.
VFR OR HIGH END MVFR CIGS SHOULD OCCUR OCASIONALLY WITH SHOWERS AND
ISOLATED THUNDERSTORMS AFT 03Z...AND ERODE INTO SOLID MVFR CONDTIONS
AT OR NEAR 09Z TIME FRAME. IF COLD FRONTAL BOUNDARY RELAXES ITS
FORWARD PROGRESSION CONVECTION COULD LAST INTO 12Z TIME PERIOD.
SE WINDS WILL INCREASE INTO THE AFTN BUT RELAX LATE TONIGHT
AS FRONTAL BOUNDARY APPROACHES. VSBYS MAY OCCASIONALY DROP TO
HIGH END MVFR WITH SHOWERS/TSTORMS.

SAT...MVFR POSSIBLE EARLY IN THE MORNING. WINDS BECOMING WEST
5-10 KTS.
SUN...VFR. WSW WINDS 5-10KTS.
MON...VFR. NNW WINDS 10KTS.
TUE...VFR. NW WINDS 5-10KTS.

&&

.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 ACCUMULATINON OF TWO TO
FOUR INCH SWATH OF RAINFALL OVER PORTIONS OF FARIBAULT AND FREEBORN
COUNTIES ON WEDNESDAY NIGHT...AND POTENTIAL FOR TRAINING SHOWERS
AND THUNDESTORMS 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...AJZ
HYDROLOGY...AJZ