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000
FXUS63 KMPX 031046
AFDMPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
446 AM CST TUE DEC 3 2013

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 348 AM CST TUE DEC 3 2013

AFTER SEVERAL DAYS OF HORRIBLE NCEP MODEL CONSISTENCY...CONFIDENCE
IN THIS WINTER STORM HAS INCREASED NOW THAT THE DEFIANT NAM AND GFS
FINALLY JUMPED ON BOARD WITH THE UKMET...GEM...AND ECMWF IN THEIR
06Z RUN. A WINTER STORM WARNING HAS BEEN POSTED FOR MUCH OF CENTRAL
AND WESTERN MINNESOTA WITH THIS FORECAST PACKAGE BEGINNING TONIGHT
AND RUNNING THROUGH WEDNESDAY NIGHT. MORE DETAILS SHORTLY.

EARLY THIS MORNING...WIDESPREAD DENSE FOG HAS FORMED ACROSS WESTERN
MINNESOTA...AND IT HAS BEEN SHOWING SIGNS OF THICKENING UP FURTHER
EAST TOWARD THE TWIN CITIES AND ALONG THE I-35 AND I-90 CORRIDORS.
WE MAY NEED TO EXPAND THE DENSE FOG ADVISORY EASTWARD SHORTLY. THE
FOG WILL BE SLOW TO IMPROVE WITH THE LOW SUN ANGLE AND WIDESPREAD
CLOUDS TODAY. IN FACT...THE LAMP GUIDANCE IS KEEPING IT AROUND
THROUGH THE DAY. ONE THING THAT MAY HELP THE FOG TO IMPROVE WILL BE
OCCASIONAL LIGHT RAIN/SNOW DEVELOPING LATER THIS MORNING. THE
ADVISORY CURRENTLY GOES THROUGH 9 AM...BUT IT WILL PROBABLY NEED TO
BE EXTENDED AT LEAST INTO THE EARLY AFTERNOON.

WEAK ISENTROPIC LIFT IN A VERY MOIST ATMOSPHERE WILL BRING
OCCASIONAL LIGHT RAIN AND SNOW ACROSS THE ENTIRE AREA TODAY AND THIS
EVENING. INCREASED POPS TO CATEGORICAL TODAY AND THIS EVENING...BUT
AMOUNTS WILL BE LIGHT. ONLY EXPECTING AN INCH OR TWO OF SNOW TODAY
AND THIS EVENING BEFORE THE MAIN ROUND BEGINS LATER TONIGHT.

BY TONIGHT...THE TROUGH DIGGING INTO THE FOUR CORNERS REGION WILL
BRING A DEVELOPING SURFACE LOW FROM OKLAHOMA TONIGHT INTO EASTERN
IOWA WEDNESDAY. THE SYSTEM WILL BE UNDERGOING A NEGATIVE TILT
TRANSITION AND WIDESPREAD SNOW WILL DEVELOP ON THE BACKSIDE OF THE
LOW...ENVELOPING THE AREA FROM SOUTHWEST TO NORTHEAST LATE TONIGHT. THE
SNOW COULD BECOME HEAVY AT TIMES BY WEDNESDAY MORNING. ACCUMULATIONS
LATE TONIGHT WILL RANGE FROM 1 TO 3 INCHES...EXCEPT ACROSS FAR
SOUTHERN MN AND WESTERN WI WHERE THERMAL PROFILES WILL PROMOTE MORE
OF A MIX. HERE...A HALF INCH CAN BE EXPECTED. AS MENTIONED
BEFORE...NCEP MODELS HAVE FINALLY SNAPPED IN LINE AND CONFIDENCE HAS
INCREASED SUCH THAT A WARNING WAS PRUDENT.

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 348 AM CST TUE DEC 3 2013

LONG TERM BEGINS WITH THE BRUNT OF THE WINTER STORM OVER THE AREA
WEDNESDAY...INTO WEDNESDAY NIGHT. FOLLOWING BEHIND THE STORM WILL BE
STRONG NORTHWEST WINDS...WHICH WILL CAUSE SIGNIFICANT BLOWING AND
DRIFTING SNOW IN THOSE AREAS RECEIVING THE SNOW. TEMPERATURES
WILL DROP OFF SHARPLY WEDNESDAY NIGHT AND THE COLDEST AIR OF THE
SEASON WILL AFFECT THE AREA FOR THE REMAINDER OF THE WEEK.

MODELS ARE FINALLY COMING INTO SOME FORM OF CONSENSUS. IT TOOK THE
GFS UNTIL THE 06Z.03 RUN TO DO IT. THE SURFACE CYCLONE DEVELOPS TO
THE LEE OF THE ROCKIES/OKLAHOMA PANHANDLE TONIGHT AND WILL LIFT
NORTHEAST AND DEEPEN OVER CENTRAL WISCONSIN WEDNESDAY. THERE WAS A
WOBBLE IN THE 00Z ECMWF...WHICH DID LIFT THE SURFACE LOW EVER SO
SLIGHTLY TO THE WEST. IT LIFTED ITS QPF A BIT FARTHER TO THE WEST
AS WELL. THE OTHER MODELS HAVE TRENDED TO MORE SOUTHWEST TO EAST
CENTRAL MN...INTO NORTHWEST WISCONSIN. AS THE LOW LIFTS NORTHEAST
INTO WISCONSIN ...THERE MAY BE A WINTRY MIX AFFECTING A PORTION OF
WEST CENTRAL WISCONSIN IN THE MORNING...BUT WILL SWITCH OVER TO
JUST SNOW IN THE AFTERNOON...AS DYNAMICS TAKE OVER AND COOLS THE
COLUMN. THE STRONG NORTHWEST WINDS FOLLOWING THE LOW WILL GENERATE
BLOWING AND DRIFTING SNOW AND NEAR BLIZZARD CONDITIONS IN OUT
STATE MINNESOTA WEDNESDAY AFTERNOON AND WEDNESDAY NIGHT. THE
HEAVIER SNOW WILL AFFECT THE MINNESOTA PORTION OF THE CWA
WEDNESDAY AND LIFT NORTHEAST OVER THE NORTHEAST CWA LATE
AFTERNOON...AND WEDNESDAY EVENING. LOOKS LIKE A GOOD 6-9 INCH SNOW
IN THE HEAVIER SNOW BAND.

FOLLOWING THE STORM...ARCTIC AIR WILL BE DRAWN EAST OVER THE AREA
THROUGH THE REMAINDER OF THE WEEK.. WIND CHILLS MAY BECOME AN
ISSUE THURSDAY NIGHT AND FRIDAY. THE LONGER TERM MODELS WERE IN
FAIR AGREEMENT WITH ANOTHER TROUGH AFFECTING THE REGION OVER THE
WEEKEND. THIS WILL HAVE TO MONITORED AS WELL...WITH VERY HIGH
SNOW/LIQUID RATIOS. VERY COLD AIR DRAINS SOUTH AFTER THIS SYSTEM
AS WELL.  IT APPEARS WINTER IS HERE.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1104 PM CST MON DEC 2 2013

MAIN PRECIP SWATH HAS SHIFTED NE OF ALL TAF SITES BUT PLENTY OF
LOW LEVEL MOISTURE WITHIN AN ELY FLOW IS LEADING TO LOW STRATUS
AND FOG DEVELOPMENT. IN ADDITION...MOST OF THE PRECIP HAS BECOME
-DZ/-SHRA...AND MAY EVEN BE A FINE LINE BETWEEN -DZ AND BR/FG BUT
REGARDLESS IT IS CAUSING SIGNIFICANT VSBY REDUCTION. AM NOT
EXPECTING FZDZ...BUT SLIGHT LIFT AND A SLIGHT DRY LAYER MAY WELL
DEVELOP THE FINE PRECIP IN WRN WI THAT COULD CAUSE DZ TO FREEZE ON
SOME SURFACES SO FZDZ CANNOT BE COMPLETELY RULED OUT FOR KRNH-
KEAU. OTHERWISE...PRECIP WILL RETURN BY LATE MRNG TMRW AND DEVELOP
ACRS ALL TAF SITES DURG THE DAY...ESP AS -RA. -RA WOULD LIKELY
HELP SCOUR OUT SOME OF THE LOWER CLOUDS AND IMPROVE VSBY SO HAVE
ADVERTISED MVFR CONDS MIDDAY...THEN FOLLOWED BY A CHANGEOVER TO
-SN WHICH WILL REDUCE CONDS TO IFR-OR-WORSE TMRW EVE INTO TMRW
NIGHT. MAINLY E WINDS PREVAIL...INCRG TO ARND 10 KT BY MIDDAY
TMRW...THEN WINDS LOOK TO SWING AROUND TO WNW OVERNIGHT TUE NIGHT.

KMSP...TRICKY START TO THE 03/06Z TAF DUE TO CEILING VARIABILITY
BETWEEN UPPER-END IFR AND LOW-END MVFR...ESP WHEN COMPARED TO
SURROUNDING TERMINALS AND SEEING KMSP AS HAVING THE HIGHEST
CEILING. THAT SAID...AM STILL LOOKING FOR IFR CONDS TO PREVAIL
BEFORE DAYBREAK AND THRU THE FIRST HALF OF TUE AS PLENTY OF LLVL
MOISTURE REMAINS IN PLACE. AS PRECIP DEVELOPS FROM THE S...MAINLY
IN THE FORM OF -RA...BOTH CEILINGS AND VISIBILITY WILL IMPROVE TO
THE MVFR RANGE. THIS WILL ONLY BE SHORT-LIVED THRU LATE AFTN AS
THE P-TYPE CHANGES TO -SN AND IFR CONDS RETURN TMRW EVE THRU TMRW
NIGHT. WINDS WILL BE MAINLY E THRU MUCH OF TUE...THEN DROP TO
LGT/VRBL AS THE CENTER OF LOW PRES SHIFTS NEAR THE AREA...
FOLLOWED BY NW WINDS AT ARND 10 KT.

/OUTLOOK FOR KMSP/
WED...MVFR CIGS. CHC SN. WINDS NW 15-25 KTS.
THU...MAINLY VFR. MVFR CIGS POSSIBLE. WINDS WNW 10-15 KTS.
FRI...VFR. WINDS WNW 5-10 KTS.


&&

.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO 6 AM CST
     THURSDAY FOR MNZ069-070-076>078-082>085.

     DENSE FOG ADVISORY UNTIL 9 AM CST THIS MORNING FOR MNZ041-042-
     047>049-054>058-064>067-073>075-082-083-091-092.

     WINTER STORM WARNING FROM 9 PM THIS EVENING TO 6 AM CST THURSDAY
     FOR MNZ041>045-047>068-073>075.

WI...WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO 6 AM CST
     THURSDAY FOR WIZ024>028.

     WINTER STORM WARNING FROM 9 PM THIS EVENING TO 6 AM CST THURSDAY
     FOR WIZ014>016-023.

&&

$$

SHORT TERM...BORGHOFF
LONG TERM...DWE
AVIATION...JPC