Small Craft Advisory 201, NWS Fairbanks, AK

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
334 AM AKDT SAT OCT 22 2016

.DISCUSSION...

Models...Good run to run continuity and they all initialized well
against the 22/06Z surface analysis. There are differences as you
go out in time between the models, but they are trending toward
similar solutions concerning the Bering Sea storm midweek. Short
term will go with a blend leaning toward the current forecast and
making only minor adjustments in timing.

Aloft...At 500 hpa...Long wave trough associated with a 500 dam
low 400 nm north of Demarcation Point exited to the east
overnight. A ridge with 540 dam heights that extend north over the
Chukchi Sea is sliding over the west coast, ridging extends to the
northwest into Siberia. A rapidly moving shortwave will swing
around the low over the arctic to be over the northwest coast this
morning, the central arctic plain this afternoon, and exits the
state early Sunday morning. The ridge over the west coast will
move inland over the western interior with a 556 dam center
developing over Bristol Bay and ridging extending northwest over
the Siberian coast. A 514 dam low that moves over the western
Aleutians this afternoon will move to the northern Kamchatka
Peninsula by Sunday afternoon with a shortwave extending southeast
over the Pribilof Islands to the Western Alaska Peninsula. As the
ridge slides east the shortwave will move northeast over the
Bering Strait and lower Yukon Delta late Monday morning, then
works its way over the top over the ridge to lie from Nuiqsut to
Bettles to Tanana by early Tuesday morning. The ridge will slide
over the eastern third of the state by Tuesday morning as the
next, stronger, shortwave moves to the central Aleutians by
Tuesday morning, and over the west coast by Tuesday afternoon. At
850 hpa...A gradual warming trend across the area that will see
temperatures slowly rise to around zero celsius for most areas by
midweek and to around 5 above over the western interior. Winds
over St Lawrence Island Tuesday are in the 75 kt range.

Surface...Ridging has built east between the ranges with a 1024 mb
center near Bettles and a 1027 mb center over Nunivak Island that
is moving east over mainland Alaska. A 995 mb low in the Gulf of
Alaska will weaken and dissipate near the southeast panhandle
coast tonight. Ridging will continue to build over the interior
tonight with 1028 mb centers over Fairbanks and Ruby. A 972 mb low
will move over the western Aleutians this afternoon and into the
eastern Bering Sea tonight. An associated low in the north Pacific
will move to just south of Dutch harbor by Sunday morning at 1003
mb. Ridging over mainland Alaska will continue to slide east in
Canada Sunday as a 1031 mb center develops over the upper yukon
flats. A weather front associated with the low in the western
Bering Sea will move to the central Bering Sea Sunday afternoon
and to the eastern Bering Sea Monday as it decays. Ridging will
persist over the eastern 2/3rds of the state as a series of lows
moves through the Bering Sea through mid week.

Arctic Coast and Brooks Range...A 992 mb low over the arctic
continues to spin waves east over the arctic coast through the
weekend. This will keep the area cloudy with only a few breaks.
Flurries with periods of light snow will prevail. Snowfall
amounts generally less than 3 inches, but the central northwest
coast, the western Brooks Range, and east of the Dalton Highway
in the Eastern Brooks Range could see 4 to 6 inches of snow by
Sunday afternoon. Visibility will be generally good with the
greatest impact being the snowfall. Winds are on a general trend
down. The strongest winds will be on the eastern arctic coast this
morning with gusts around 40 mph and those winds will be coming
down through the day to 15 to 25 mph. Winds for the remainder of
the area will be in the 10 to 20 mph range from the southwest to
west. Temperatures steady today then a slow warming the next
couple days.

West Coast and Western Interior...Some snow showers north of the
Bering Strait, otherwise conditions will be pretty nice. Some
marine stratus over the coastal areas, but inland areas will
remain partly cloudy for the most part. Generally less than an
inch of accumulation north of the Bering Strait. Winds light and
variable turning from the south as the high pressure center moves
inland tonight. Southeast to south winds over the coastal areas
and St Lawrence Island will increase this afternoon and overnight.
Winds on St lawrence Island will increase to around 30 mph gusting
to 45 mph tonight and those stronger winds will make their way to
the coastal areas west of Nome and the Bering Strait by Sunday
afternoon. Temperatures will warm as south flow up the coast
pulls warmer air north. The storm moving into the Bering Sea
Monday and Tuesday has the potential produce significant and
potentially damaging winds similar to a storm that impacted St
Lawrence Island in late December 2010 and Early January 2011, the
exception being that temperatures will be much warmer.

Central and Eastern Interior...The front that brought the first
significant snowfall to most of the interior continues to move
east this morning with snow falling in the eastern Alaska Range,
upper Tanana Valley, Fortymile Country, and upper Yukon Valley
southeast of Fort Yukon. The heaviest snowfall has ended, so will
end the Winter Weather Advisory for zone 226. Still expect up to 3
inches of new snow in the upper Tanana Valley, and locally in the
Fortymile Country south of the Taylor Highway. Snow will taper off
from the west ending this afternoon. Winds light and variable as
high pressure moves over the area. Temperatures steady into Monday
then a slow warming trend into mid week.

&&

Coastal Hazard Potential Days 3 and 4...Models are in better
agreement, but the ECMWF is still showing better run to run
continuity. Models do indicate a trend taking the center of the
storm just a bit further west with the highest winds and seas to
the west of St Lawrence island. This could still produce some
significant winds on St Lawrence island and produce storm surge up
to 5 feet at Gambell and 3 feet at Savoonga Tuesday.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...

Heavy Freezing Spray Warning FOR PKZ235-PKZ240-PKZ245.

Small Craft Advisory FOR PKZ240-PKZ245.

Gale Warning FOR PKZ210.

&&

SDB OCT 16