Winter Storm Warning 9, NWS Fairbanks, AK

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
502 AM AKST SUN NOV 21 2010

.DISCUSSION...
BIG NORTH PACIFIC HIGH ALOFT AND FAIRLY SHARP RIDGE EXTENDING NWD
ACROSS ALASKA AND THE BEAUFORT SEA WILL REMAIN THE DOMINANT
WEATHER FEATURE FOR A FEW MORE DAYS...BUT BIG CHANGES IN THE
WORKS. BEFORE THAT THOUGH...EXTENDED PERIOD OF RAIN OVER MUCH OF
THE CENTRAL AND SRN INTERIOR IS IN STORE.

ALTHOUGH MODELS IN BASIC AGREEMENT IN THE SHORT TERM ON LARGE
SCALE FEATURES...THERE ARE SUBSTANTIAL DIFFERENCES BETWEEN THE
NAM AND GFS/ECMWF WITH TEMPS OVER THE INTERIOR...WITH NAM BEING
MUCH COOLER. IN THE INTERIOR...MODELS AND MOS APPEAR TO HAVE
SFC/BOUNDARY LAYER MUCH TOO COLD...AND THIS IS HAVING AN IMPACT ON
PCPN TYPE FORECAST. IN ANY CASE...MOS IS HAVING REAL PROBLEMS.

STARTING WED THE PATTERN BECOMES MORE PROGRESSIVE WITH THE RIDGE
BEING PUSHED AND HEIGHTS CRASH ACROSS MAINLAND ALASKA AND THE GULF
OF ALASKA. THIS WILL BRING A RAPID RETURN TO MORE SEASONABLE TEMPS BY
THE WEEKEND.

NORTH SLOPE...FOR TODAY...BRISK EAST WIND ALONG THE FAR EAST COAST
AS COLD HIGH HANGS ON NEAR BANKS ISLAND. WINDS SHOULD DIMINISH A
BIT TONIGHT. OTHER AREAS RECORD OR NEAR RECORD WARMTH. COOLER
AIRMASS WILL BEGIN TO MOVE ACROSS THE SLOPE FROM WEST TO EAST
STARTING MONDAY.

WEST COAST...INCOMING SLUG OF PRECIP SHOULD BE PRETTY MUCH ALL
RAIN EXCEPT ALONG THE SOUTH SLOPES OF THE BROOKS RANGE...AND EVEN
THERE SOME RAIN POSSIBLE. CHUKOTKA LOW WILL MUCH COOLER AIR INTO
WESTERN ZONES TONIGHT BUT EASTWARD ADVANCE WILL BE STALLED BY
NEXT NWD MOVING N PACIFIC LOW.

INTERIOR...PROLONGED RAIN EVENT LOOKS TO BE IN THE WORKS FROM SW
ZONES AROUND THE ALASKA RANGE AND INTO THE CENTRAL INTERIOR. THE
PRIMARY QUESTIONS ARE HOW FAR NORTH AND EAST THE RAIN REGIME GETS.
AT THIS TIME THE MODELS ALL SEEM TO SUGGEST THAT NORTH OF 66N
PRECIP SHOULD REMAIN LARGELY SNOW. SOUTH OF THERE PRECIP SHOULD BE
ALL RAIN AT LEAST THRU TUE.

COASTAL HAZARD POTENTIAL DAYS 3 AND 4...NONE

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WATCH FOR AKZ216-AKZ219-AKZ220-AKZ221-AKZ222-AKZ223-
AKZ225-AKZ227.

SMALL CRAFT ADVISORY FOR PKZ200.

GALE WARNING FOR PKZ220-PKZ225-PKZ245.

BRISK WIND ADVISORY FOR PKZ215-PKZ230-PKZ235-PKZ240.
&&

RT NOV 10