Area Forecast Discussion
Issued by NWS Twin Cities, MN

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933
FXUS63 KMPX 020506
AFDMPX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1106 PM CST MON FEB 1 2016

.UPDATE...
ISSUED AT 1100 PM CST MON FEB 1 2016

UPDATED TO INCLUDE 06Z AVIATION DISCUSSION BELOW.

&&

.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 315 PM CST MON FEB 1 2016

MODELS HAVE COME IN LINE TODAY FOR THE MOST PART REGARDING THE
STORM SYSTEM SET TO STRIKE TUESDAY...WITH THE NORTHWARD SHIFT
NOW EMBRACED. THE INCREASED CONFIDENCE MEANT PULLING THE TRIGGER
ON THE WARNINGS...AND DRAGGING THEM FARTHER NORTH TO INCLUDE THE
TWIN CITIES AND MOST OF WEST CENTRAL WISCONSIN.

THE SURFACE LOW IS FORECAST TO TRACK FROM THE TX/OK PANHANDLE TO
REACH NORTHEASTERN KS BY 18Z TUESDAY...THEN LIFT TO LAKE MI
TUESDAY NIGHT. THIS PLACES THE SOUTHEASTERN THIRD OF MINNESOTA AND
WEST CENTRAL WISCONSIN IN THE FAVORABLE AREA FOR SNOW ACCUMULATIONS
AND STRONG NORTHERLY WINDS. SNOW ONSET TIME LOOKS TO BE BY SUNRISE
ACROSS SOUTHERN MN /I-90 CORRIDOR/...AND BETWEEN 9 AM AND 11 AM
FOR THE TWIN CITIES/EAU CLAIRE. WINDS WILL ALSO INCREASE TO AROUND
25-30 MPH SUSTAINED ACROSS SOUTHERN MN BY EARLY AFTERNOON...THUS
SETTING THE STAGE FOR BLIZZARD CONDITIONS ACROSS MUCH OF SOUTHERN
MN...ESPECIALLY WHILE THE SNOW IS FALLING. SLIGHTLY LOWER WIND
SPEEDS EXIST TO THE NORTH OVER CENTRAL MN/WI...BUT THEY WILL STILL
BE STRONG ENOUGH TO YIELD AREAS OF BLOWING SNOW.

THE SREF PROBABILITIES ILLUSTRATE RARE /AND IMPRESSIVE/ 70-90
PERCENT PROBABILITIES OF SNOWFALL RATES EXCEEDING ONE INCH PER
HOUR ACROSS THE WARNING AREAS DURING THE DAY TUESDAY...AS WELL
AS A 70 PERCENT PROBABILITY OF A DENDRITIC GROWTH ZONE DEPTH OF
100MB. THIS GIVES INCREASING CONFIDENCE IN THE WARNINGS.

.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 315 PM CST MON FEB 1 2016

THE LONGER TERM CONCERN REMAINS TIMING OF THE WINTER STORMS EXIT
AND TRANSITION TO A MORE AMPLIFIED NORTHWEST FLOW PATTER LATE IN
THE WEEK AND INTO EARLY NEXT WEEK.

THE WINTER STORM WILL BE HIGHLY OCCLUDED BY EARLY TUESDAY
EVENING. THIS LEAVES THE CLOSED UPPER CIRCULATION TO TRANSLATE
EAST OVER THE CWA. WILL CONTINUE THE CATEGORICAL SNOW THROUGH
ABOUT MIDNIGHT...WITH TRAILING POPS OFF TO THE EAST THEREAFTER.
WINDS ARE EXPECTED TO REMAIN STRONG DEVELOPING FROM WEST TO EAST
OVER SOUTH CENTRAL MN DURING THE EVENING...WITH THE AREA ALONG AND
SOUTH OF THE MN RIVER VALLEY...AND ALONG I90 SEEING BLIZZARD
CONDITIONS.

THE SYSTEM EXITS EARLY WEDNESDAY MORNING WITH PERHAPS SOME
LINGERING LIGHT SNOW AND BLOWING SNOW EARLY. EXPECTING OVERALL
IMPROVEMENT IN CONDITIONS THROUGH WEDNESDAY AFTERNOON.

THE UPPER FLOW PATTERN BEGINS TO TRANSITION TO MORE AMPLIFIED
PATTERN. TWO WAVES WORKING SOUTHEAST THROUGH CANADA THROUGH THE
END OF THE WEEK...BUT WOULD PRODUCE VERY LIGHT AMOUNTS OF
SNOW...AND MAINLY OVER THE EASTERN PORTION OF THE CWA. THE
ECMWF...GFS AND CFSV2 ARE ALL SHOWING A MUCH COLDER ARCTIC AIR
INTRUSION OVER THE EASTERN CONUS BEGINNING INTO EARLY NEXT WEEK
AND LINGERING THROUGH MUCH OF THE WEEK.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1100 PM CST MON FEB 1 2016

FOG AND LOW CEILINGS WILL MAKE FOR IFR-OR-WORSE CONDITIONS
OVERNIGHT INTO TOMORROW MORNING...IN ADVANCE OF THE SN/BLSN
EXPECTED FOR MUCH OF THE AREA TMRW INTO TMRW NIGHT. ONLY KAXN
LOOKS TO ESCAPE THE -SN...BEING TOO FAR DISPLACED FROM THE CURRENT
LOW PRES TRACK. HOWEVER...DID INCLUDE A PROB30 MENTION TO ACCOUNT
FOR A SMALL CHANCE OF -SN SHIFTING THAT FAR N LATE AFTN INTO THE
EVE...ALONG THE LINES OF THE WAY THE MODELS HAVE BEEN TRENDING
SINCE YESTERDAY. CEILINGS WILL LIKELY BE BOUNCING BETWEEN IFR AND
LOWER-END MVFR BEFORE THE -SN BEGINS. ONCE THE SNOW MOVES IN FROM
THE S...VSBYS WILL LIKELY DROP TO 1SM OR LESS IN SN/BLSN WHILE
CEILINGS DROP TO IFR LEVELS. WINDS FROM THE NE AND N WILL INCREASE
TO THE 15G25KT AREA BY MIDDAY TMRW...AND POTENTIALLY TO 20G30KT BY
TMRW EVE.

KMSP...SMALL VFR POCKETS HAVE EVOLVED AROUND KMSP LATE THIS
EVE...BUT THIS IS EXPECTED TO BE SHORT-LIVED AFTER 02/06Z
INITIALIZATION. LOWER-END MVFR CEILINGS /MAINLY BETWEEN 010-015
HEIGHTS/ WILL PREVAIL OVERNIGHT THEN SLIGHTLY RISE ABOVE 1700 FT
BY LATE TMRW MRNG AS THE -SN COMMENCES. CONDITIONS ARE EXPECTED TO
DETERIORATE RAPIDLY BY MIDDAY...WITH SOLID IFR CONDS LIKELY AND
POTENTIALLY INTO LIFR OR VLIFR SHOULD HEAVIER BANDS OF SNOW
DEVELOP AND/OR CEILINGS DROP FURTHER THAN CURRENTLY ADVERTISED.
SNOWFALL RATES OF 1 IN/HR CANNOT BE RULED OUT...ESPECIALLY DURG
THE AFTN HOURS AND POTENTIALLY HAVING SIGNIFICANT IMPACTS TO THE
AFTN/EVE PUSH.

/OUTLOOK FOR KMSP/
WED...VFR. WIND NW 10-15 KTS.
THU...VFR. WIND SW 5-10 KTS.
FRI...MAINLY VFR. SLGT CHC MVFR/-SN. WIND S 5-10 KTS.

&&

.MPX WATCHES/WARNINGS/ADVISORIES...
WI...WINTER STORM WARNING FROM 9 AM TUESDAY TO 6 AM CST WEDNESDAY FOR
     WIZ015-016-023>028.

     WINTER WEATHER ADVISORY FROM 9 AM TUESDAY TO 6 AM CST WEDNESDAY
     FOR WIZ014.

MN...WINTER STORM WARNING FROM 9 AM TUESDAY TO 6 AM CST WEDNESDAY FOR
     MNZ060-062-063-067>070-075>078.

     WINTER WEATHER ADVISORY FROM 9 AM TUESDAY TO 6 AM CST WEDNESDAY
     FOR MNZ051>053-058-059-061-064>066.

     BLIZZARD WARNING FROM 6 AM TUESDAY TO 6 AM CST WEDNESDAY FOR
     MNZ073-074-082>085-091>093.

&&

$$

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



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