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Northern Alaska forecast discussion...updated 
National Weather Service Fairbanks Alaska
335 PM akdt sun Aug 30 2015

Synopsis...
aloft...
long wave trough over Mainland Alaska will move east over the next
several days as a long wave ridge now over the eastern Bering Sea
builds east to a position over Mainland Alaska Wednesday. The ridge will
slowly weaken through next weekend as a series of short wave
troughs moves into this ridge from the west. This means the
current showery and cold pattern over all of northern Alaska will
short east over the next several days with the West Coast warming
Monday and Tuesday while the interior and Arctic warms Tuesday and Wednesday. Will
see normal to above normal temperatures from Thursday through next
weekend.

A vertically stacked low near Huslia will move south to near
Anchorage by 4am Monday. Scattered snow and rain showers around this
feature will become isolated north of the low tonight. Expect
numerous showers in northwest facing slopes with up to 2 inches snow
accumulation above 1000 feet tonight. There are northwest winds gusting to
30kt west of the low that will decrease north of the low.

A short wave trough over the southern Yukon territory will move to
Mayo NE by 4am Monday...to Northway north by 4pm Monday...to Tok to Old
Crow by 4am Tuesday and then weakening. Expect widespread rain and
snow with this trough that will become scattered rain and snow
showers Monday night and Tuesday. Expect snow level 2000-3000 feet with 1-2
inches of snow.

850 mb temperatures range from -3c to -6c over northern Alaska
with freezing levels 1000-2000 feet. Monday will see little change
over the interior or North Slope while the West Coast of Alaska
will see warming of 2-4c Monday. Tuesday will see little change on the
West Coast but a 2-4c warming over the interior and North Slope.

Surface...
a low near yellowknife will move to 200 nm east of inuvik as a
985 mb low by 4am Monday with an occluded front from the low north
over the Beaufort Sea. These features will then weaken slowly
through Tuesday. Will see rain and snow spreading over the NE corner
of Alaska late tonight through Tuesday. 1-2 inches of snow possible
above 1000 feet.

A ridge of high pressure lies over the northern Bering Sea and
western Chukchi Sea. The ridge will build east over the Arctic
coast and interior of Alaska through Tuesday. This will cause west
winds to develop over the eastern Arctic coast with the strongest
winds near gale force developing Monday over the Barter Island area.
This will cause decreasing clouds over the West Coast of Alaska
tonight and over the western and central interior Monday. Frost will
be likely in the western and central interior low lying areas
early Monday.

A weather front moving in the central Bering Sea Tuesday will move to
the northern Bering Sea Wednesday. This will bring easterly winds 30 knots
and widespread rain to the eastern Bering Sea Tue-Wed.

&&

Discussion...
models initialize well and similar through Tuesday aloft...and show
similar pattern Wednesday through next weekend with sight differences
in timing of short waves. At the surface the NAM develops a
stronger low in MacKenzie Bay on Tuesday than the GFS or ecmf. Prefer
the weaker GFS solution as the main low remains south of the area
and the warm air pushing north at low levels over the cold water
is not inducive to deepening of the surface low. Still expect
westerly gale force west winds near Barter Island Monday night and
Tuesday even using GFS solution...but need to be aware of potential
for more winds.



Coastal hazard potential days 3 and 4...
high surf near Shishmaref ending this afternoon.
High surf possible near Barter Island Monday into Tuesday.
None Wednesday through Friday.

&&

Fire weather...
gradual decreasing relative humidity in the western and central interior Monday and
eastern interior Tuesday and Wednesday.

&&

Hydrology...
Moose Creek dam is expected to continue backing up flow through
Monday or Tuesday. This will keep the chena high from the Moose Creek dam
downstream to its mouth at the Tanana river through Monday or Tuesday.
This will cause areas that now have minor flooding on the lower
chena to continue through Monday or Tuesday.

&&

Afg watches/warnings/advisories...
high surf advisory for akz204-akz207.

Flood Advisory for akz222

Frost advisory for akz222.

Small Craft Advisory for pkz200-pkz210-pkz240-pkz245.

Gale Warning for pkz245.
&&

$$

Aug 15

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