Blizzard and High Wind in Alaska, December 29 to 31, 2012

NORTHERN ALASKA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE FAIRBANKS AK
628 AM AKST SAT DEC 29 2012

.DISCUSSION...
967 MB LOW OVER BRISTOL BAY AT 3 AM SAT WILL CURVE NORTHWESTWARD
DURING THE NEXT 24 HOURS...FILLING TO ABOUT 983 MB 100 NM S OF ST
LAWRENCE ISLAND BY 3 AM SUN. WILL CONTINUE THE WINTER STORM
WARNINGS FOR ZONES 211-212-213-214-215-216. CURRENT MODEL SNOW
AMOUNTS LOOK MARGINAL EXCEPT IN THE NULATO HILLS...BUT SNOW AND
BLOWING SNOW SHOULD REDUCE VISIBILITY. ADDITIONALLY...SOME LIGHT
FREEZING RAIN POSSIBLE IN ZONE 214 TODAY.

THE NEXT SYSTEM MOVING NWD OUT OF THE PACIFIC IS PROGGED
BY CURRENT GFS/ECMWF TO BE NEAR OR W OF KODIAK IS BY 9 AM SUN
WITH CENTRAL PRES AROUND 960 MB...THEN MOVE NWWD AS IT FILLS. MEAN
OF GFS AND ECMWF PROG POSITIONS FOR 3 AM WED WOULD PUT THE CENTER
NEAR DALL POINT...CENTRAL PRES WKNG TO AROUND 978 MB. THIS SYSTEM
WILL LIKELY PRODUCE ANOTHER EPISODE OF SIGNIFICANT SNOW OVER
THE WEST COAST AND WESTERN INTERIOR.

GUSTY CHINOOK WINDS HAVE DEVELOPED IN ALASKA RANGE PASSES...WIND
ADVISORY HAS BEEN POSTED FOR ZONE 223. WIND ADVISORIES FOR
ZONES 225-226 HAVE BEEN UPGRADED TO HIGH WIND WARNINGS.
A PROGRESSIVE SOUTHERLY FLOW PATTERN ALOFT WILL CONTINUE OVER THE
INTERIOR AS SEVERAL SHORT WAVE TROUGHS MOVE NWD THROUGH A MEAN
RIDGE POSITION. THE FIRST SHORT WAVE WILL MOVE NWD ACROSS THE AK
RANGE TODAY...NAM MAXES OUT LOW LEVEL WINDS ALOFT BELOW 700 MB AT
60-85 KT ACROSS THE AK RANGE. A SECOND BURST OF SHORT WAVE ENERGY
WILL MOVE NWD ACROSS THE AK RANGE SUN...LOW LEVEL WINDS ALOFT
ACROSS THE AK RANGE MAXING OUT AT 60-90 KT. THIS TO BE FOLLOWED BY
A THIRD SHORT WAVE TRANSITING THE AK RANGE TUE. CHINOOK WINDS IN
AK RANGE PASSES WILL LIKELY PERSIST FOR MOST OF THE TIME THROUGH
TUE.

NAM12 CROSS SECTION ALONG THE LEE OF THE ALASKA RANGE INDICATES
THE STRONG SOUTH WINDS ALOFT OVER THE EASTERN PART OF THE RANGE
SHIFTING TO SOUTHWEST SUN NIGHT. THIS INCREASES THE POTENTIAL FOR
LOCALLY STRONG WINDS OUT OF CHANNELED AREAS ALONG THE ALASKA FROM
NORTHWEST OF TOK TO THE DOT LAKE AREA. NAM12 TIME SECTION FOR THE
ROBERTSON RIVER AREA ON THE AK HIGHWAY INDICATES SOUTH WINDS AS HIGH
AS 70 KT ALOFT BELOW 700 MB SHIFTING TO SOUTHWEST BY MIDNIGHT.
HAVE INDICATED LOCAL 50 MPH WIND GUSTS POSSIBLE ALONG THAT STRETCH
OF THE AK HIGHWAY IN ZONE 224 FOR SUN NIGHT. FUTURE MODEL RUNS
WILL NEED TO BE EVALUATED CLOSELY...A WIND ADVISORY OR HIGH WIND
WATCH MAY BE NEEDED FOR THIS AREA IF SUBSEQUENT MODEL RUNS LOOK
SIMILAR.

COASTAL HAZARD POTENTIAL DAYS 3 AND 4...NONE

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FOR AKZ223.

WINTER STORM WARNING FOR AKZ211-AKZ212-AKZ213-AKZ214-AKZ215-
AKZ216.

HIGH WIND WARNING FOR AKZ225-AKZ226.

GALE WARNING FOR PKZ210-PKZ225.

BRISK WIND ADVISORY FOR PKZ200-PKZ215-PKZ220-PKZ230.
&&

DEC 12