000
FXUS63 KMPX 040938
AFDMPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
338 AM CST WED DEC 4 2013

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 339 AM CST WED DEC 4 2013

ONLY MINOR ADJUSTMENTS TO ONGOING HEADLINES FOR THIS EVENT.  WILL
HOLD ONTO THE DENSE FOG ADVISORY IN THE FAR SOUTHEAST CORNER OF THE
AREA...ALTHOUGH THIS MAY BE CANCELLED EARLY. THE WINTER WEATHER
HEADLINES STILL LOOK GOOD FOR THE SNOW EXPECTED ACROSS THE REGION.
MAY BE A TIGHT GRADIENT ACROSS THE SOUTHEAST CWA.

LOCAL RADAR MOSAIC SHOWING A NICE BAND OF MODERATE SNOW LIFTING
NORTHEAST OVER THE CENTRAL PORTION OF THE AREA NOW.  THIS WILL IMPACT
THE MORNING COMMUTE WITH A COUPLE OF INCHES POSSIBLE BY MID MORNING
OVER THE EAST CENTRAL MINNESOTA INTO WEST CENTRAL WISCONSIN.

FOLLOWED A GFS/ECMWF BLEND OVERALL...ALTHOUGH ALL DETERMINISTIC
MODELS ARE IN FAIR AGREEMENT OVERALL.  THE 00Z ECMWF AND GEM ARE
VERY SIMILAR WHICH HAS BEEN THE CASE THROUGHOUT MOST OF THE MODEL
RUNS UN TO NOW.  THEY REMAIN THE SLOWEST OF THE MODELS...SO WILL
LINGER SOME HIGH POPS INTO THE EVENING ACROSS THE NORTHERN PORTION
OF THE AREA AS THE SYSTEM LIFTS NORTHEAST AND DEEPENS.  THERE WILL
LIKELY BE A MIX OF PRECIPITATION/RAIN/SLEET AND SNOW OVER A PORTION
OF WEST CENTRAL WISCONSIN THROUGH THE DAY.  THE SNOW WILL
TRANSITION TO THE MIX BY NOON AS THE SURFACE LOW DEEPENS OFF TO THE
EAST OF THE AREA.  THE HEAVIER SNOW/HIGHER QPF IS DISPLACED
A BIT BETWEEN MODELS...BUT STILL LOOKS LIKE THE BEST PLACEMENT WILL
REMAIN OVER CENTRAL MINNESOTA...SHIFTING NORTHEAST INTO NORTHWEST
WISCONSIN BY AFTERNOON.

LINGERING LIGHT SNOW AND INCREASING GUSTY WINDS WILL DEVELOP BEHIND THE
SYSTEM THIS AFTERNOON AND INTO THURSDAY.  AS THE ARCTIC AIR FILTERS
IN IN THE WAKE OF THE SURFACE LOW...WE SHOULD SEE SOME GUSTS
APPROACH AT LEAST 30 KTS OVER THE SOUTHWEST PORTION OF THE CWA.
THIS WILL DEVELOP CONSIDERABLE BLOWING AND DRIFTING SNOW INTO
TONIGHT. WILL HAVE TO MONITOR THE POSSIBILITY OF NEAR BLIZZARD
CONDITIONS IF THE WINDS COINCIDE WITH ANY SIGNIFICANT FALLING SNOW.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 339 AM CST WED DEC 4 2013

THE WINTER STORM WILL HAVE WINDED DOWN BY DAYBREAK
THURSDAY...AND WITH THE EXCEPTION OF SCATTERED LINGERING
FLURRIES...THE SNOWFALL SHOULD BE OVER. A VERY TIGHT SURFACE
PRESSURE GRADIENT IN THE WAKE OF THE TROUGH WILL YIELD BLUSTERY
WEST/NORTHWEST WINDS AND RESULTANT AREAS OF BLOWING SNOW.
TEMPERATURES WILL STRUGGLE TO WARM UNDER THE INFLUENCE OF LLVL
COLD AIR ADVECTION...AND HIGHS ARE EXPECTED TO TOP OUT FROM AROUND
5 ABOVE /WEST CENTRAL MN/...TO 10 ABOVE /EAST AND SOUTH CENTRAL
MN/...TO BETWEEN 10 AND 15 /WEST CENTRAL WI/. THE BRISK WINDS AND
VERY COLD TEMPERATURES WILL COMBINE TO YIELD DAYTIME WIND CHILL
VALUES BETWEEN 10 BELOW AND 20 BELOW ON THURSDAY. FURTHERMORE...LOWS ON
THURSDAY NIGHT WILL DROP TO BETWEEN ZERO AND 10 BELOW...AND WHILE
WINDS WILL BE WEAKER...OVERNIGHT WIND CHILLS WILL LIKELY PLUMMET
TO BETWEEN 15 BELOW AND 30 BELOW BY DAYBREAK FRIDAY.

COLD AND DRY HIGH PRESSURE DOMINATES THE REGION THROUGH THE
WEEKEND...ALTHOUGH 850MB FLOW SHIFTS TO MORE OF A
SOUTH/SOUTHWESTERLY DIRECTION ON SUNDAY. THIS SHOULD ALLOW FOR A
MODERATION FROM SATURDAY HIGHS IN THE 5 BELOW TO 5 ABOVE RANGE TO
SUNDAY HIGHS IN THE 5 ABOVE TO 15 ABOVE RANGE. THE LLVL FLOW
TRANSITION WILL BE ACCOMPANIED BY THE ARRIVAL OF WEAK SHORTWAVE
ENERGY...AND THEREFORE SNOWFALL CHANCES FROM SATURDAY NIGHT INTO
MONDAY. THERE ARE STILL SOME NOTABLE TIMING/STRENGTH/PLACEMENT DIFFERENCES
BETWEEN THE GFS AND ECMWF...BUT IT LOOKS LIKE A DECENT POTENTIAL
FOR A QUICK SHOT OF ACCUMULATING SNOWFALL.

NEXT WEEK CONTINUES TO FEATURE REINFORCING SHOTS OF ARCTIC AIR
INTO THE UPPER MIDWEST...WITH TEMPERATURES RUNNING AROUND 15 TO
30 DEGREES BELOW NORMAL FOR EARLY DECEMBER.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1129 PM CST TUE DEC 3 2013

IFR-OR-WORSE CONDS EXPECTED TO PREVAIL THROUGH THE REST OF THE
OVERNIGHT HOURS AND MOST OF THE DAY TDA A POTENT LOW PRES CENTER
SLOWLY TRUDGES ITS WAY ACRS THE REGION THRU WED EVE. P-TYPE
ISSUES WILL BE MITIGATED DUE TO COLDER AIR INTRUSION FROM THE
W...MAKING THE PREVAILING P-TYPE AS SNOW OF VARYING INTENSITIES.
IN ADDITION...MODEL GUIDANCE HAS REDUCED ANY SEMBLANCE OF A WARM
LAYER ALOFT TO NOTHING /EXCEPT FOR KEAU WHICH WILL BE CAUGHT IN
SOME WARMER AIR SO THERE MAY BE A VARIETY OF P-TYPES IN THE FIRST
HALF OF THE TAF PERIOD/. USING SHORT-TERM MODEL GUIDANCE...PRECIP
ONSET WILL OCCUR IN THE PRE-DAWN HOURS...GENERALLY IN THE 08Z-11Z
TIMEFRAME...THEN THE HEAVIEST BANDS OF PRECIP WILL OCCUR IN THE
LATE MRNG TO EARLY AFTN HOURS...ESP FOR CENTRAL MN EASTWARD IN
THE 12Z-16Z TIMEFRAME FOR ONSET. MOST DEGRADED CONDS WILL OCCUR
DURING THAT MIDDAY PERIOD TMRW THEN CONDS WILL GRADUALLY IMPROVE
LATE TMRW INTO TMRW EVE. THE IMPROVEMENT WILL ROUGHLY COINCIDE
WITH A SWING IN WIND DIRECTIONS AS WINDS SHIFT FROM NE TO N AND
NW...AND THE PRES GRADIENT INCRS OVER WRN MN WHICH WILL INCRS WIND
SPEEDS. CONDS IMPROVE SLIGHTLY TMRW EVE TO THE LOWER RANGES OF
MVFR.

KMSP...PREVAILING IFR-OR-WORSE CONDS ARE EXPECTED AT THE TERMINAL
THRU MUCH IF NOT ALL OF WED...WITH SOME SLIGHT IMPROVEMENT WED EVE.
THE MAIN ISSUES ARE THE TIMING OF THE ONSET OF SNOW AND THE TIMING
OF ANY HEAVY BANDS OF SNOW. ATTM...ONSET OF SUSTAINED -SN LOOKS
TO BE IN THE 09Z-11Z AREA WITH HEAVIER BANDS STARTING TO AFFECT
THE TERMINAL IN THE 13Z-15Z TIMEFRAME. THE HEAVIER BANDS LOOK TO
LAST UNTIL 18Z-20Z THEN CONDS SLOWLY IMPROVE AS THE PRECIP BACKS
OFF. THERE IS ALSO THE TIMING OF THE DIMINISHING SNOWFALL WITH THE
INCRS IN WINDS...SO VSBY MAY BE STRONGLY AFFECTED BY BLOWING SNOW.
WINDS REMAIN NE THRU TNGT THEN GRADUALLY BACK TO N AND NW...INCRG
IN SPEED TMRW AFTN TO THE 15G22KT AREA.

/OUTLOOK FOR KMSP/
THU...MVFR CIGS PSBL. NW WIND 10-20 KT.
THU NIGHT...VFR. W WIND 5-15 KT.
FRI...MVFR CIGS PSBL. W WIND 5-15 KT.
FRI NIGHT...VFR. W WIND LESS THAN 10 KT.
SAT...VFR. VARIABLE WIND 5 KT OR LESS.


&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY UNTIL 6 AM CST THURSDAY FOR MNZ069-070-
     076>078-082>085-091.

     WINTER STORM WARNING UNTIL 6 AM CST THURSDAY FOR MNZ041>045-
     047>068-073>075.

     DENSE FOG ADVISORY UNTIL NOON CST TODAY FOR MNZ092-093.

WI...WINTER WEATHER ADVISORY UNTIL 6 AM CST THURSDAY FOR WIZ024>028.

     WINTER STORM WARNING UNTIL 6 AM CST THURSDAY FOR WIZ014>016-023.

&&

$$

SHORT TERM...DWE
LONG TERM...LS
AVIATION...JPC