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Northern Alaska forecast discussion 
National Weather Service Fairbanks Alaska
339 am akdt Friday Oct 21 2016

Discussion... major differences in the solutions out in to the mid
range again today. Still quite a bit of timing and strength issues
in the extended forecast for the potential storm next week. Good
run to run continuity in the short term. For the storm in the
extended the European model (ecmwf) has had good run to run continuity, but the GFS
is still jumping around looking for a solution to settle on. Will
go with a blend of the latest solutions and the current database
for the short term. 500 hpa...long wave trough lies over the state with a
494 dam low 78n 170w. The trough extends south over kuparuk to
Beaver to Lake Minchumina this morning. The low will move to 77n
145w by Saturday morning with the trough lying over the Beaufort
Sea to MacKenzie Bay to Glennallen. The low and trough continue
to move east Saturday. As the trough moves east, ridging builds
over the central Bering Sea today and moves to the eastern Bering
Sea by Saturday morning with ridging extending northwest over the
Gulf of Anadyr. A rapidly moving shortwave will move out of
northern Siberia to wrangel island tonight, over the northwest
coast early Saturday morning, and over the Yukon territory by
Sunday morning. The ridge will move over the West Coast Saturday
night, and the western interior Sunday morning with ridging
extending northwest over the Chukchi Sea and wrangel Island. A 512
dam low will move north into the western Bering Sea Saturday and
continue to the northwest Bering Sea by Sunday morning with a
shortwave extending southeast over Dutch Harbor. The low will move
north into Siberia and the shortwave will move north over the
Bering Strait and Chukchi Sea brushing over the coastal areas
through Monday morning. At 850 hpa...temperatures around 13 below
over Fairbanks this morning. A slow warming trend through the
weekend across the area south of the Brooks range will push
temperatures to around zero celsius by Monday evening.

Surface...troughing over the eastern third of the state continues
to move east and will be over the Yukon territory by Friday
afternoon. A 1003 mb low over the Northwest Arctic will move
southeast to 300 nm northeast of Barrow late Friday at 993 mb. The
associated cold front will move over the northwest coast this
morning, staying primarily north of the Brooks range, and exit
the state late tonight. A 1026 mb high just south of the Gulf of
Anadyr will continue to move southeast to be over Nunivak Island
late Friday night with ridging extending northwest over Old Crow
yt. Ridging will continue to build between the ranges with
multiple 1027 mb centers over the area Saturday. The high center
will continue to build through Saturday night as it is pushed east
a bit and a 1032 mb high center will settle in over the upper
Yukon Flats by Sunday morning, the center then drifts southeast
into the Yukon territory. The remnants of Typhoon Haima will move
into the western Bering Sea Sunday night and impact the West Coast
Monday and Tuesday.

Arctic coast and Brooks range...cloudy conditions will persist. A
period of snow as the cold front moves west to east across the
area today. Winds coming up a bit as the front moves through and
that will produce some poor visibility in blowing snow as the
winds increase from the west to 25 to 35 mph east of Barrow. From
Barrow west winds will generally be west at 10 to 20 mph. Winds
will diminish across the area on Saturday to 5 to 15 mph. Heaviest
snowfall will be in the Brooks range with up to 4 inches possible
east of the Dalton Highway. Along the coast snow will persist, but
accumulation will be limited to 1 to 2 inches.

West Coast and western interior...some snow showers over the
Chukchi Sea and adjacent coastal areas today as well as the
northern Seward Peninsula. Accumulations generally light through
Saturday morning. Widns along the coast west to northwest at 5 to
15 mph. Lighter winds inland. Generally a clearing pattern for the
middle Yukon and lower Yukon Delta today. No significant change in
temperatures through Saturday, then a slow warming trend.

Central and eastern interior...snow continues to fall to the
southeast of Fairbanks this morning and it will taper off and
move east through the morning. Snowfall continues in the eastern
Alaska Range and it will slow down through the morning as well.
The heaviest snowfall has been west of the Richardson Highway
overnight. Expect another inch or 2 of snow along the Richardson
Highway south of Delta Junction through the evening. Also, in the
upper Tanana Valley, along the Taylor Highway, and in the
fortymile country up to 2 inches of snow will fall through
Saturday morning. Winds generally southwest to west to 10 mph
becoming light and variable late Saturday. Will continue the
advisory for zone 226 as snow continues to fall.


Coastal hazard potential days 3 and 4...models still indicating a
significant storm moving into the Bering Sea Monday night through
Tuesday evening. European model (ecmwf) has had much better run to run continuity
with the system, so will stick with it until the GFS settles on a
similar solution, or they trend to the same solution. Biggest
impact being indicated at this time is significants winds and wind
driven seas.


Afg watches/warnings/advisories...

Winter Weather Advisory for akz226.

Heavy freezing spray warning for pkz235-pkz240-pkz245.

Small Craft Advisory for pkz235-pkz240-pkz245.



Sdb Oct 16

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