Small Craft Advisory 166, NWS Fairbanks, AK

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
504 AM AKDT Sun Oct 14 2018

.DISCUSSION...
The main forecast challenges will be winter weather related
including the potential for accumulating snow over the Interior
and eastern Brooks Range as well as precipitation type. Another
round of strong south gap winds in the Alaska Range will come into
play as well as the strength may facilitate downslope/chinook
conditions over the southern Interior. The 14/00Z model solutions
are in good agreement through the middle to late this week.

Aloft, at 500 mb, a 526 dam currently near St. Matthew Island will
drift northwest and dissipate today. A 516 dam low 200 miles south
of Unalaska will rotate north into Bristol Bay by Monday
afternoon with the upper level ridge over the northwest Pacific
Ocean builds north over the the far Eastern Interior and western
Canada. The upper level ridge will continue to build north as it
shifts east Monday and Tuesday while another round of strong
southerly flow increases over the Alaska Range and Interior. The
low over Bristol Bay will remain quasi-stationary and weaken
through Wednesday and as it weakens flow will become southwest
over the Interior.

At the surface, a 990 mb low over St. Matthew Island will weaken
today. A 969 mb low 300 miles southwest of Unalaska will move to
be over Cold Bay Monday afternoon as a 973 mb, then into Bristol
Bay as a 976 mb low by Tuesday morning, and finally will remain
quasi-stationary in the Bristol Bay region through Wednesday. A
1029 mb surface high pressure centered over eastern Siberian
Russia extends east roughly 200 miles offshore of the Arctic Coast
and will gradually build across the Arctic with a 1027 mb center
forming over the Beaufort Sea by Monday afternoon.

Eastern and Central Interior...Light snow continues over the
southeastern Brooks Range in zone 218 and foothills in zone 220
with gusty winds generating blowing snow and poor visibility over
Eagle Summit along the Steese Highway this morning where winter
Weather Advisories are ongiong through noon. Snow will taper off
later this morning and early this afternoon. Over the Central
Interior where skies are clearing, areas of fog are possible with
locally dense fog possible. South gap winds will ramp up Monday
afternoon with gusts flirting with advisory criteria (50 mph) in
Isabel Pass along the Richardson Highway by Monday evening with
gap winds continuing through Tuesday. The next round of
precipitation will come with a front lifting north over the Alaska
Range Monday evening. The chinook winds will limit the chances
for precipitation with this front immediately north of the Alaska
Range from Fairbanks south. To the north, there is the potential
to see 3 to 5 inches of snow north of the Yukon River including
the foothills and southern slopes of the Eastern Brooks Range. In
the area between Fairbanks and the Yukon River, there is the
potential to see a wintry mix of snow and freezing rain.
Precipitation will continue into Tuesday evening before tapering
off.

North Slope and Brooks Range...Periods of light snow will continue
over the northeastern Brooks Range and North Slope east of the
Dalton Highway through the afternoon and taper off tonight with
an additional inch or two expected. The next round of
precipitation will come Tuesday and Tuesday night as a front lifts
north and will bring 2 to 5 inches of snow to the eastern North
Slope and Brooks Range. Gusty northeast to east winds will develop
along and offshore of the Beaufort Sea coast Tuesday morning
possibly sustained around 30 mph with gusts around 40 mph. These
strong winds will continue into Tuesday night and combined with
fresh falling snow could result in blowing snow and reduced
visibility.

West Coast and Western Interior...A break in the unsettled,
showery pattern will continue through Monday morning before the
low currently south of Unalaska moves into Bristol Bay. An
associated front will move north over the area spreading
precipitation over the area. Precipitation type will remain rain
over the south, while snow will be the primary precip type over
the southern slopes of the western Brooks Range. Unsettled and
showery pattern will persist into the middle of the week as the
low remains in the area. East to northeast winds will ramp up over
the Bering Sea and Norton Sound tonight and will continue through
Wednesday. Winds will be the strongest in the vicinity of St.
Lawrence Island and the Bering Strait.

Coastal Hazard Potential Days 3 and 4...None.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory for AKZ218-AKZ220.

Small Craft Advisory for PKZ210-PKZ225-PKZ230.
&&

LTH OCT 18