Area Forecast Discussion
Issued by NWS Twin Cities, MN

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000
FXUS63 KMPX 241021
AFDMPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
421 AM CST MON NOV 24 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 421 AM CST MON NOV 24 2014

THE BROAD UPPER TROUGH PIVOTING ACROSS THE CENTRAL CONUS TODAY AND
TONIGHT WILL FACILITATE PROLONGED LIFT LOCALLY...A BIT STRONGER
OVER WEST CENTRAL WI. EXPECT SNOWFALL ACCUMULATIONS IN THE 2 TO 4
INCH RANGE FROM DURAND...TO EAU CLAIRE TO LADYSMITH. THE HOPWRF
SUPPORTS THIS THEORY...WITH ALL FOUR MEMBERS INDICATING ADVISORY
CRITERIA SNOWFALL BEING MET BY SUNSET THERE. ALTHOUGH THE
LANDSCAPE TYPICALLY DOES NOT SUPPORT WIDESPREAD BLOWING SNOW AND
THERE WAS SIGNIFICANT FOG/SNOWMELT YESTERDAY..STILL COULD SEE
REDUCED VISIBILITIES IN THE FALLING/BLOWING SNOW OVER WEST CENTRAL
WI. THE WESTERN GRADIENT OF THE ACCUMULATING
SNOW WILL LIKELY BACK UP TO THE EASTERN EDGE OF THE TWIN
CITIES....WITH UP TO AN INCH POSSIBLE FROM THE TWIN CITIES SOUTH
TO MANKATO AND FAIRMONT.

MEANWHILE...TO THE WEST OVER WEST CENTRAL AND SOUTH CENTRAL
MINNESOTA...WINDS WILL BE CONTINUE HOWLING AT 30 MPH WITH GUSTS
TO 45 MPH UNDER THE INFLUENCE OF THE TIGHT SFC PRESSURE
GRADIENT. THE WIND ADVISORY THEREFORE LOOKS TO BE IN GOOD SHAPE. A NEARLY
STEADY TO FALLING TEMP TREND WILL ENSUE TODAY IN THE WAKE OF THE
FRONT...WITH LOWS TONIGHTTEMPERED SOMEWHAT BY LINGERING CLOUDS.
LOWS WILL GENERALLY RANGE FROM 8 TO 16 DEGREES.


.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 421 AM CST MON NOV 24 2014

THERE WILL BE TWO CHC/S OF PRECIPITATION IN THE EXTENDED PERIOD.
ONE WILL OCCUR LATE TUE/EARLY WED...WHILE ANOTHER AFFECTS THE
REGION LATE IN THE WEEK.

MODELS HAVE TRENDED FURTHER SW WITH TUE/WED SYSTEM...WITH THE SFC
LOW NOW MOVING ACROSS FAR SW MN...AND INTO CENTRAL IA BY WED
MORNING. THE 50H VORT MAX IS ALSO FURTHER SW CREATING A DILEMMA ON
HOW FAR EAST/NE DOES THE MEASURABLE PRECIPITATION OCCUR BEFORE DRIER
AIR ERODES THE DEEPER MOISTURE. THIS AIR MASS REMAINS LIMITED ON THE
AMT OF MOISTURE IT CAN RING OUT BASED ON PRECIPITABLE WATER VALUES
AND MIXING RATIOS. THE ONLY PROBLEM WOULD BE ENHANCED FORCING WHICH
MAY AID IN A SMALL AREA OF HIGHER QPF AMTS. WOULD LIKE TO STAY CLOSE
TO A BLEND OF THE EC/WPC QPF AMTS WHICH CREATE AN AREA OF 0.08 TO
0.13 THRU MOST OF THE EVENT. THIS TRANSLATES TO 1-3 INCHES OF
SNOW...WITH LOCALLY HIGHER AMTS NE OF THE SFC LOW TRACK. THE CIPS
ANALOG GUIDANCE FOR THIS EVENT HAS A NARROW BAND OF 2-4 INCHES FROM
WC MN SE TO NEAR KAEL. CURRENT HIGH CHC/LOW LIKELY POPS SEEM
REASONABLE BASED ON THE CURRENT TREND OF THE SW SHIFT.

AFTER THIS EVENT...THE COLDEST AIR FOR THE NEXT 7-10 DAYS WILL
SETTLE ACROSS THE UPPER MIDWEST. A STRONG THERMAL BOUNDARY WILL
LIKELY SET UP ACROSS THE PLAINS LATE IN THE WEEK AS WINDS SHIFT TO
THE SW/S. THIS WILL SET THE STAGE FOR ANOTHER LIGHT SNOWFALL EVENT
SOMETIME LATE THU/FRIDAY. HOWEVER...ANY DEVIATION TO THE RETURN FLOW
AND THERMAL BOUNDARY WILL LEAD TO PROBLEMS WITH QPF. CHC POPS AT
THIS TIME SEEMS REASONABLE.

AS SAID BEFORE...THE COLDEST AIR IN THE NEXT 7-10 DAYS WILL OCCUR
LATE THIS WEEK AS THE UPPER RIDGE BEGINS TO BREAK DOWN IN THE
WESTERN CONUS. THIS WILL LEAD TO A MODIFIED PACIFIC/CANADIAN AIR
MASS TO FILTER ACROSS OUR REGION AS THE UPPER FLOW BECOMES MORE
ZONAL NEXT WEEK. TEMPS WILL LIKELY RISE TO NEAR OR ABV FREEZING FOR
THE FIRST WEEK OF DECEMBER BASED ON THIS TYPE OF PATTERN CHG.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1149 PM CST SUN NOV 23 2014

A RATHER COMPLEX 12 TO 18 HOURS AHEAD IN TERMS OF PRECIP
TYPE...INTENSITY...AND DURATION. PRECIPITATION OVER WI REMAINS
MAINLY RAIN AT TAF ISSUANCE TIME...BUT IT IS CHANGING TO SNOW OVER
FAR EASTERN MN AND WILL CONTINUE TO TRANSITION FURTHER EAST
OVERNIGHT. BEHIND THE MAIN PRECIP...FREEZING DRIZZLE IS PUSHING
INTO WESTERN MN AS DRIER AIR ALOFT MOVES IN. THIS DRY AIR SHOULD
CONTINUE PROGRESSING EASTWARD UNTIL IT INTERSECTS THE MOISTURE
WITH THE MAIN SYSTEM TO THE EAST. THUS...ALL MN TAF SITES HAVE A
THREAT FOR ICING OVERNIGHT INTO MONDAY MORNING. AS THE COLUMN
CONTINUES TO COOL INTO THE FAVORED SNOW GROWTH RANGE...PRECIP SHOULD
TURN BACK TO ALL SNOW BY LATE MONDAY MORNING. WINDS WILL REMAIN
STRONG...WITH GUSTS BETWEEN 25-35 KT THROUGH MUCH OF THE PERIOD.

KMSP...LIGHT SNOW TO START THE PERIOD WILL TAPER OFF AFTER
08 OR 09Z...THEN TRANSITION TO POTENTIALLY FREEZING DRIZZLE
MONDAY MORNING AS DRIER AIR MOVES IN ALOFT. SNOW SHOWERS OR
FLURRIES WILL RETURN FROM LATE MORNING INTO EVENING.

/OUTLOOK FOR KMSP/
TUE...VFR. WINDS W 5-10 KT BECOMING SE.
WED...MVFR/IFR CHC -SN EARLY. WINDS NW 10-15KTS.
THU...VFR. WINDS LIGHT/VARIABLE.


&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR MNZ054>056-064-065-
     073>075-082>084-091>093.

WI...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR WIZ016-
     026>028.

&&

$$

SHORT TERM...LS
LONG TERM...JLT
AVIATION...BORGHOFF








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