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fxak69 pafg 171409 
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Northern Alaska forecast discussion
National Weather Service Fairbanks Alaska
509 am akst Tue Jan 17 2017

Synopsis...
aloft...
deep and cold long wave trough over Mainland Alaska and the
eastern Bering Sea will weaken slowly through the weekend as
several short waves eject their cold air and energy northeast out
of the trough. This means that northern Alaska will remain very
cold this week with periods of slightly less cold as short waves
and the clouds and snow associated with them move north over the
state.

At 850 mb all of northern Alaska has temperatures of -23c to -33c
and will remain that cold through Thu. Clear inland valleys have
now cooled into the 40s below under this airmass with temperatures
in the teens and 20s below along the coasts.

Surface...
a 995 mb low over the Seward Peninsula will weaken slowly through
Thu. This is causing north winds along the West Coast and Brooks
range of Alaska which will weaken slowly through Thu. The north
winds pushing very cold air over the ice will pick up heat and
moisture from open leads in the ice and cause isolated snow
showers along north facing coasts through Thu. North winds through
Brooks range passes are causing very cold wind chills that will
become less severe after midnight tonight as winds decrease.

An occluded front stretching from the low east to Fort Yukon to
Whitehorse will move to Kotzebue to Arctic Village by 3pm
Tue...and to Kotzebue to Nuiqsut then northeast by 3am Wed...then
stationary and weakening. There is light snow along this front
from Bettles east that will taper off from the southwest today.
West winds and cold winds chills blowing over the far eastern
interior behind this front over zones 220 and 224 will decrease
this afternoon.

A low pressure trough stretching from the low to McGrath will move
to Kotzebue to Delta Junction by 3pm Tue...to kotezbue to Arctic
Village by 3am Wed and then dissipating. Will see clouds clearing
with temperatures dropping rapidly along this trough today and
tonight. Surface temperatures will drop into the 40s below with
ice fog developing near rivers and towns.

A low moving north over the Gulf of Alaska Wed will move over the
southern Yukon territory Wed night and Thu. This will bring a
chance of snow Wed night and Thu to the interior east of Fairbanks
along with a slight rise in temperatures.

A low pressure trough over the Gulf of Alaska coast will persist
through Wed causing gusting north winds through Alaska Range
passes along with cold wind chills.

&&

Discussion...
models initialize well and show similar solutions through 3pm
Wed...then start to see differences in location and timing of
features. The biggest difference is on the low moving from the
southeast Bering Sea on Thu into SW Alaska Fri. At this point
favor the ecmf solution from Wed night on which takes the Bering
Sea low on a much more southerly track than the GFS does.

&&

Afg watches/warnings/advisories...
Wind Chill Advisory for akz205-akz206-akz207-akz208-akz217-
akz218-akz225-akz226.

Winter Weather Advisory for akz220-akz224.

Heavy freezing spray warning for pkz210.

Brisk Wind Advisory for pkz220-pkz225.

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