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Northern Alaska forecast discussion 
National Weather Service Fairbanks Alaska
103 PM akdt Thursday Sep 18 2014

Discussion... pretty good agreement in the short term...Canadian is
a little slower in pushing the trough into the interior on Sunday.
Pretty good agreement on the precipitation developing over the
middle Yukon valley Friday and the interior on Saturday...not
much agreement on precipitation as we get further out into Monday
and Tuesday. 500 hpa...527 dam closed low over the Nushagak Delta
will move south over the shumagin island by Saturday morning
continuing south into the North Pacific by Sunday morning as it
absorbs a 540 dam low over the northern Gulf. The low spins back
into the northern Gulf by Monday afternoon. A 530 dam low will
move over wrangel island Friday evening moving east over Barrow by
Saturday evening then move northeast over the high Arctic. The
associated shortwave will move over the northwest coast early
Saturday morning...then extend from Barrow south to Nikolai
Saturday evening...and from deadhorse south to Delta Junction
Sunday afternoon...exiting out of the state early Monday. Ridge
builds over central Bering Sea and moves over the eastern Bering
Sea by Saturday evening...moving over the West Coast Sunday. At
850 isotherm has moved to the northern slopes of the
Brooks range and along the West Coast today...and will move to lie
from Old Crow to Bettles to Ruby to Marshall then back to the
northwest over St Lawrence Island by Saturday morning. By Sunday
morning it will lie from Old Crow to Delta Junction to Sleetmute
then northwest to St Lawrence Island.

Surface...a 973mb low in in the central Bering Sea will spin north
to Prince William Sound...then into the interior overnight. The
frontal system will lie southwest to northeast across the area
extending from around Sleetmute to Old Crow. Good moisture feed
from the south combining with shortwave will produce up to one
half inch of rain between the Yukon river and alcan border. The
exception will be the southeast corner which will be chinooked
out. The front will drag out to the northeast with precipitation
ending Sunday morning. As second wave will swing around from the
southeast into the interior spreading rain over the southeast
corner of the state and possibly some flurries into the Fairbanks
area by Monday afternoon.

Arctic coast and plain...stratus and fog rule the day again. Not
expecting the stratus to go away. The GOES MVFR probability 4km
shows high probability of MVFR over most of the Arctic and
offshore areas. The npp viirs day night band from 18/1736z
confirms solid cloud deck over the area with multiple decks of
clouds. Easterly flow will continue over the area through Sunday
before turning northeast. Fog will be around but not expecting
any dense fog tonight. Winds increasing as the gradient over the
Arctic tightens between the low inland and the high in the
Arctic. Winds generally 10 to 20 miles per hour increasing to 15 to 25 miles per hour
with gusts around 40 miles per hour overnight...then winds decreasing to 10
to 25 miles per hour gusting to 35 miles per hour for Saturday. Strongest winds will be
from Barrow east. Drizzle or light rain will change over to
freezing drizzle as the cold air moves east...then change to snow
by noon Saturday. No significant snowfall expected this time

West Coast and western interior...increasing clouds little tricky
out west as stationary front develops over the middle Yukon valley
with rain spreading over the area from Anvik to Ambler and the
Nulato Hills east to well as the upper Kuskokwim
valley. Rain will taper off through the morning Saturday. Rainfall
amounts will be in the one tenth to one half inch range...highest
over the lower Yukon Delta. Winds generally 5 to 15 miles per hour from the
north. Cold air moves in along the coast beginning early Saturday
spreading southeast through Sunday. Not expecting much in the way
of snow...but a few flurries over the northern areas would not be

Interior...increasing clouds tonight with rain spreading south to
north Friday night into Saturday morning. Rainfall amounts will be
in the one tenth to one half inch range...tapering off late
Saturday. Front moving in from the southeast Sunday will bring
another bout of rainfall to areas from Manley Hot Springs
southeast. Heaviest amounts with the second system will be over
the fortymile country. Would not be surprised to see a flurry
around Fairbanks on Sunday night with the upper trough and cold
air moving into the area. Temperatures continue the slow spiral
down with highs only in the 50s and lows in the 40s through
Sunday...then highs around 50 and lows in the lower 30s next week.
Winds generally light across the area.


Coastal hazard potential days 3 and 4...none.


Hydrology...rivers all on the way down.


Fire weather...none.


Afg watches/warnings/advisories...

Small Craft Advisory for pkz200-pkz220-pkz225-pkz235-pkz240-

Gale Warning for pkz210-pkz240-pkz245.

Heavy freezing spray for pkz510.



Sdb Sep 14

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