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fxak69 pafg 142112 
afdafg

Northern Alaska forecast discussion
National Weather Service Fairbanks Alaska
1212 PM akst Fri Dec 14 2018

Synopsis...
aloft...
the long wave pattern consisting of of a trough over Mainland AK,
the eastern Bering and the Gulf of Alaska with a ridge over
western Canada will persist for most of the next week. A series
of weak short wave troughs will move north over the interior and
North Slope of Alaska bringing periods of light snow and clouds.
His pattern will keep western Alaska colder than normal into next
week, while the interior and North Slope will be near to just
below normal in temperatures, vacillating between zero when
cloudy and snowy, to 20-30 below when clear. Expect snow fall
amounts to be 1 inch or less per 12 hours period over the next
several days.

A 4940m h500 low near Buckland will move to Wainwright by 3pm
Sat, persist into sun, then drift north on Mon. This feature is
vertically stacked and a surface feature will drift north with
this. A short wave trough stretching east from this low to Barter
Island will move to Kotzebue to Umiat to Barter Island by 3am Sat,
to Wainwright to Barrow east by 3pm Sat. A second short wave
trough stretching from the low to the Bering Strait will move to
Kotzebue to the Yukon Delta by 3am Sat, then weakening. A broad
area of mid-level stratus and light snow under the low aloft and
troughs aloft will persist under these features, with clouds and
snow clearing south of the troughs on Sat.

Surface...
an Arctic warm front that lies from Isabell pass to Chicken will
move to Fairbanks to Circle by 3am Sat with a cold front from
Fairbanks to Denali. This front will move by 3pm Sat to Old Crow
to a wave near Tanana, with a cold front from Tanana to McGrath.
By 3am sun the warm front will move just north of Barter Island
with a 1004 mb low near Barter Island with a cold front from
Barter Island to McGrath. Expect light snow along with front with
2 inches near the western Alaska Range through sun while the
interior will be about 1 inch total today through Sat night.

A polar warm front in the Gulf of Alaska will move to Valdez to
Northway by 3am sun, and to Denali to Tanana to Old Crow by 3pm
sun, then with a surface low forming along the front near Tanana
Sun night, with the low moving to Bettles Mon. Expect light snow
with less than one inch accumulation along the warm front Sat
night through sun, then expect several inches of snow Sun night
and Mon with the low in the central and western interior.

&&

Discussion...
models initialize well at the surface at 12z, with the exception
of the high pressure over NE Russia being about 8mb stronger than
any models initialize. Models appear to initialize well aloft,
but with many unknowns due to no Alaska raobs north of Anchorage
at 12z.

Model solutions similar through 3pm sun, with just slight
differences showing up by Mon. Will generally go with the GFS into
Mon, but boost winds 3-5 kt over the northern Bering through
tonight to account for the models initializing too week over NE
Russia.

Beyond that, models agree on long wave trough persisting into
next week over Mainland AK, then either weakening or retrograding
next weekend. Upshot is that near or slightly below normal
temperatures and dry conditions are expected through the next
week.

Coastal hazard potential days 3 and 4...
north winds 25g35 kt Bering Strait and St Lawrence Island
much of the time now through Tue will keep surf elevated and
could cause freezing spray at to blow onshore at Savoonga and
Little Diomede. Do not expect high surf as fetch length has
decreased with Chukchi Sea beginning to freeze.

&&

Afg watches/warnings/advisories...
heavy freezing spray warning for pkz210.

Small Craft Advisory for pkz210.

Brisk Wind Advisory for pkz220.
&&

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