Area Forecast Discussion
Issued by NWS Twin Cities, MN

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FXUS63 KMPX 030947
AFDMPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
347 AM CST TUE MAR 3 2015

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 342 AM CST TUE MAR 3 2015

OVERALL...CONFIDENCE HAS IMPROVED SOMEWHAT WITH THE EVOLUTION OF THE
SYSTEM IMPACTING THE REGION TODAY BUT SOME OF THE FINE SCALE DETAILS
HAVE YET TO COME INTO COMPLETE FOCUS DUE TO SOME CONSISTENCY ISSUES
IN THE HOURLY HRRR/RAP GUIDANCE. THE BAND OF SNOW OVER WEST CENTRAL
MN IS INDEED FORMING QUICKLY EARLY THIS MORNING IN RESPONSE TO A
RIBBON OF STRONG FORCING WITH THE MID LEVEL SHEARING
VORTICITY/FRONTOGENESIS. THE BAND IS EXPECTED TO BE ANCHORED THERE
FOR MUCH OF THE MORNING AND WILL BRING 3 TO 5 INCHES OF SNOW FROM
WEST CENTRAL TO NORTHEAST MINNESOTA. A SECOND BAND IS SHOWING SOME
BEGINNING SIGNS OF DEVELOPMENT ACROSS NORTHERN IOWA DUE TO MID/UPPER
LEVEL FORCING ON THE NORTHERN PERIPHERY OF THE UPPER JET. THIS BAND
SHOULD ALSO BRING AN ENHANCED AREA OF SNOWFALL FROM SOUTHEAST MN
INTO CENTRAL WI. THE AREA IN BETWEEN...FROM SOUTHWEST MN TO WEST
CENTRAL WI WILL REMAIN DRY UNTIL DAWN OR SHORTLY THEREAFTER BEFORE A
CONSOLIDATION OF THE TWO AREAS OF FORCING BEGIN AND THE SURFACE LOW
TRACKS TO THE SOUTH. WIDESPREAD SNOW WILL THEN OCCUR FOR A 3-4 HOUR
WINDOW THIS MORNING BEFORE THE FRONT DRIVES THE SNOW EAST BY EARLY
AFTERNOON. DUE TO THE BRIEF PERIOD OF SNOWFALL...NOT EXPECTING TOO
MUCH ACCUMULATION FROM SWRN/SCTRL MN TO WCTRL WI - MAYBE AROUND TWO
INCHES. THIS IS THE AREA PLAGUED MOST WITH UNCERTAINTY.

HOW MUCH FALLS WILL STRONGLY DETERMINE HOW FAR EAST BLIZZARD
CONDITIONS WILL REACH THIS AFTERNOON. THERE ISN/T MUCH SNOW ON THE
GROUND NOW ACROSS THE NORTHEASTERN HALF OF THE BLIZZARD WARNING.
HOWEVER...THE SNOW WILL BE FALLING DURING A PERIOD OF LIGHT WINDS
AHEAD OF THE FRONT WHICH WILL ENHANCE THE SNOW RATIO. THE POWDERY
NATURE OF THE SNOW FOLLOWED BY A VERY RAPID RAMP UP OF THE POST
FRONTAL WINDS COULD STILL LEAD TO WHITEOUT CONDITIONS. WOULD PREFER
TO SEE 3 OR 4 INCHES ON THE GROUND...BUT IT IS NOT UNHEARD OF TO
HAVE BLIZZARD CONDITIONS WITH JUST ONE OR TWO...PARTICULARLY IF IT
HAD JUST FALLEN. ALTHOUGH THERE ARE SOME RESERVATIONS WITH HOW FAR
EAST THE WARNING EXTENDS...WILL NOT CANCEL YET AND AWAIT THE
DEVELOPMENT OF THE SNOW. THE COUNTIES MOST LIKELY TO BE DROPPED
WOULD BE MEEKER...MCLEOD...SIBLEY...AND LE SUEUR.

THE WIND GRIDS STILL LOOK GOOD WITH A SWATH OF SUSTAINED 25-30 KT
AND 40+ KT GUSTS ALONG AND SOUTH OF THE MN RIVER EARLY THIS
AFTERNOON.

WINDS WILL EASE THIS EVENING AS MORE ARCTIC AIR SPILLS SOUTH. LOWS
IN THE SINGLE DIGITS BELOW ZERO LOOK LIKE A SLAM DUNK WITH SOME
TEENS BELOW POSSIBLE IN WCTRL MN. SOME WIND CHILLS WILL DROP COLDER
THAN 25 BELOW OVER CENTRAL AND WRN MN...BUT WILL WAIT FOR CURRENT
HEADLINES TO BE CANCELLED BEFORE ISSUING ANY WIND CHILL
ADVISORIES.

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 342 AM CST TUE MAR 3 2015

THE LONG TERM CONCERNS ARE THE DEVELOPMENT OF WARMING TREND LATE
IN THE WEEK AND THROUGH THE WEEKEND.

INITIAL COLD SHOT FOLLOWING TUESDAYS SYSTEM WILL LEAVE BELOW NORMAL
READINGS TO THE AREA THROUGH THURSDAY.  WILL HAVE WIND CHILL
CONCERNS OVER THE WEST PORTION OF THE CWA LATE TONIGHT INTO
WEDNESDAY MORNING...WITH WIND CHILL VALUES DROPPING TO 25 TO 30
BELOW. WINDS ARE EXPECTED TO REMAIN BREEZY THROUGH WEDNESDAY AS
THE ARCTIC AIR SETTLES INTO THE REGION. TROUGH EXTENSION OVER
NORTHEAST MN WILL DROP COLD POOL OF AIR OVER THE EASTERN AREA
DURING THE DAY WEDNESDAY. CLOUDS ARE EXPECTED TO DEVELOP INTO
WEDNESDAY AFTERNOON AS THE TROUGH MOVES ACROSS MAINLY WEST CENTRAL
WISCONSIN. WE COULD SEE A FEW FLURRIES WITH THIS FEATURE AS
WELL...BUT LIMITED THAT TO THE FAR NORTHEAST PERIPHERY OF THE AREA
FOR NOW.

THE LARGE HIGH PRESSURE AREA DROPS SOUTH OVER THE CENTRAL CONUS FOR
WEDNESDAY NIGHT/THURSDAY MORNING.  THIS WILL LEAVE LIGHTER WINDS BUT
COLDER TEMPERATURES FOR THE AREA.  READINGS MAY NOT BE COLD ENOUGH
OVER THE FRESH SNOW COVERED AREAS. WILL HAVE TO MONITOR WHAT
VERIFIES FOR TUESDAY.  WIND CHILLS WILL HAVE TO MONITORED
AGAIN...BUT DO EXPECT WINDS TO BE MUCH LIGHTER.

THE DETERMINISTIC MODELS THEN TREND TOWARD BUILDING HEIGHTS AND LESS
AMPLIFIED FLOW PATTERN OVER THE CONUS WITH LARGE UPPER RIDGE
BECOMING ESTABLISHED OVER THE WESTERN CONUS INTO THE WEEKEND.  THIS
WILL LEAVE THE AREA VULNERABLE TO BRIEF COLD FRONT INTRUSIONS BUT
TIMING OF ANY IMPULSES THAT RIDE ACROSS THE NORTHEAST PORTION OF THE
AREA IS DIFFICULT. CARRIED THE SLIGHT CHANCE POPS IN THE GUIDANCE
FOR SUNDAY AS THIS APPEARS TO GREATEST THREAT OF A MORE SIGNIFICANT
COLD FRONTAL PASSAGE.

THE LATEST CFS ENSEMBLE PLUMES WERE SHOWING A WARMING TREND LASTING
UNTIL AT LEAST THE MIDDLE OF THE MONTH.  THIS VERIFIES THE
DETERMINISTIC LONG TERM MODELS WITH THE ECMWF MOST BULLISH WITH THE
HIGHER HEIGHTS/WARMER TEMPERATURES. THE CIPS EXTENDED ANALOG THREAT
GUIDANCE TAKES US ALL THE WAY THROUGH MID MONTH...AND IS SHOWING
HIGH PROBABILITY OF ABOVE NORMAL TEMPERATURES AND RELATIVELY DRY
CONDITIONS. FOR THE MOMENT...WE DID WARM TEMPERATURES FROM EXTENDED
GUIDANCE QUITE A BIT. IF THE ECMWF VERIFIES...WE COULD BE SEEING
TEMPERATURES WARMING THROUGH THE 40S AND INTO SOME LOWER 50S FOR
PARTS OF THE AREA...EARLY NEXT WEEK.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1115 PM CST MON MAR 2 2015

WE`RE SLOWLY BUT SURELY STARTING TO SEE THE SNOW EXPAND AND EVEN
GETTING SOME GROUND TRUTH SNOW REPORTS...ESPECIALLY IN WEST
CENTRAL MN. HEAVIER SNOW MOVES IN LATE TONIGHT WITH IFR/LIFR
CONDITIONS EXPECTED FOR SEVERAL HOURS IN THE MORNING INTO THE
EARLY AFTERNOON. THE SNOW IS EXPECTED TO CLEAR FAIRLY QUICKLY
DURING THE AFTERNOON. WE SLOWED THE TIMING FOR THE ONSET OF SNOW
BY AN HOUR OR TWO AT KMSP/KRNH/KEAU.

KMSP...

WE EXPECT MINOR ACCUMULATIONS BEFORE THE MORNING RUSH /DUSTING/...BUT
THE SNOW SHOULD INCREASE IN INTENSITY AS THE MORNING PROGRESSES.
SNOW RATES SHOULD BE ROUGHLY 0.5 INCH/PER AT THEIR HEAVIEST...SO
WE DON`T EXPECT MUCH MORE THAN A COUPLE INCHES WITH THIS EVENT
BEFORE THE SNOW DIMINISHES IN THE EARLY AFTERNOON AS THE WIND
RAMPS UP. OVERALL...WE THINK THE SNOW TOTALS WILL BE A LITTLE LESS
THAN WHAT WE THAT AT THE TIME THE 18Z AND 00Z TAFS WERE ISSUES. WE
SLOWED THE ONSET OF THE SNOW THIS MORNING AND LOWERED SNOW TOTALS
SLIGHTLY.

/OUTLOOK FOR KMSP/
WED...VFR. WINDS NW 15G20 KTS.
THU...VFR. WINDS SW 5-10 KTS.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...BLIZZARD WARNING FROM 11 AM THIS MORNING TO 9 PM CST THIS
     EVENING FOR MNZ058-066-067-074>076-082>085-091>093.

     WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR
     MNZ041>045-049>053-059>063-068>070-077-078.

     WINTER WEATHER ADVISORY UNTIL 7 AM CST THIS MORNING FOR MNZ047-
     048-054>056-064.

     BLIZZARD WARNING FROM 7 AM THIS MORNING TO 9 PM CST THIS EVENING
     FOR MNZ047-048-054>056-064.

     BLIZZARD WARNING FROM 9 AM THIS MORNING TO 9 PM CST THIS EVENING
     FOR MNZ057-065-073.

     WINTER WEATHER ADVISORY UNTIL 9 AM CST THIS MORNING FOR MNZ057.

WI...WINTER WEATHER ADVISORY UNTIL 9 PM CST THIS EVENING FOR
     WIZ014>016-023>028.

&&

$$

SHORT TERM...BORGHOFF
LONG TERM...DWE
AVIATION...CLF



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