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Northern Alaska forecast discussion 
National Weather Service Fairbanks Alaska
614 am akdt Sat Aug 29 2015

Discussion...
the recent active weather across northern Alaska will continue to
become more tranquil as we progress through the weekend. Forecast
models initialized well with the large scale features over the
state and are in good agreement through at least Monday. A cold
low aloft centered near Barrow with a longwave trough extending
southeast toward the alaskan Panhandle will begin to dive
southward out of the Arctic today. By Monday the main upper low
will be over the northeast Gulf of Alaska with a remnant longwave
trough extending back across the interior and to the Arctic. This
shift in the current synoptic scale pattern is the result of
ridging building across the Bering Sea as former typhoon atsani
enters the western Bering between Kamchatka and the Aleutians on
Monday. The ridge axis will progress east to Mainland Alaska by
the middle of next week...bringing a gradual rebound in
temperatures and pleasant Fall weather for viewing the changing
colors.

In the short term...there is still some active weather to contend
with over the next 12 to 24 hours. The tight pressure gradient on
the back side of a 992 mb surface low north of Barrow continues
to produce maximum small craft northwest winds across much of the
Chukchi Sea. This low will weaken as it moves south into the
Brooks range tonight and the region of strongest winds shifts
southward to the Seward Peninsula and Bering Strait today. The
extensive ice free water in the chukchi is building seas from 6
to 10 feet and elevating storm surge levels along the coastline.
Northwest facing shores are the most vulnerable and a high surf
advisory has been issued for the Shishmaref area. Surge values
are approaching 1 foot and will not result in flooding...but some
beach erosion is possible from the wind driven waves. Winds and
seas diminish on Sunday as the surface low continues to move into
the interior and weaken.

Winter weather is still an issue over higher elevations of the
Brooks range and in Denali National Park. The most significant
snow accumulation is above 3000 feet. Snow will continue over the
Brooks range today as the surface low near near Barrow moves
southward but will taper off this evening to scattered snow
showers. The primary impact will be Atigun Pass on the Dalton
Highway. In Denali...on and off snow showers will bring a few
additional inches of snow to higher locations along the park Road
into Sunday.

Otherwise around the forecast area...scattered to isolated rain
showers...mixed with snow at higher elevations will linger
through Sunday but diminish in most areas by Monday as ridging
builds over the state.

Coastal hazard potential days 3 and 4...none

&&

Fire weather...
no issues. Minimum relative humidity values will remain high as cooler and cloudier
weather continues this weekend. A gradually warming and drying
will begin next week.

&&

Hydrology...
heavy rain in the interior ended 36 hours ago and the flood crest
moving down the chena river is approaching the Moose Creek dam.
As of 4am the US Army corps of engineers have still not activated
the flood control but the flow is nudging at the 8000 cfs
threshold...it appears the flow will barely meet criteria for
activation. Otherwise water levels on rivers in the western Alaska
Range continue to fall.

&&

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

Winter Storm Warning for akz206.

Winter Weather Advisory for akz225.

Small Craft Advisory for pkz210-pkz215-pkz220-pkz225-pkz230-
pkz245.
&&

$$

Ewp Aug 15

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