High Wind in Alaska, January 1 to 2, 2018

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
122 PM AKST Sun Dec 31 2017

.DISCUSSION...

Models...Not much change from yesterday in the solutions for the
short term. Good run to run continuity continues. Solutions
continue to make rather significant changes around 60 hours each
cycle. 31/12Z solutions initialized well against the 31/18Z
surface analysis with good positions, and feature strength.
SREF/NAM precipitation solution favored for the short term as it
handles the downslope drying of the Alaska Range and redevelops
the precipitation north of the Yukon River.

Aloft...At 500 hpa...Ridging continues to rotate northeast across
the area today and will be over the Eastern Brooks Range and
Eastern Arctic Coast tonight. A second ridge will rotate up and
merge into it with ridging pushing west over the Northwest Arctic
Coast Monday morning. A 504 dam low in the Central Bering Sea will
remain quasi stationary into Monday evening, then start moving
west as a 505 dam low moves east over the Aleutians to be over
Nikolski by Tuesday morning. A 505 dam low will move from over the
North Pacific to 200 nm south of Sand Point by Monday morning,
then over Bristol Bay Monday evening, then over the Lower Yukon
Delta by Tuesday afternoon as it weakens to 513 dam. A shortwave
currently over the Lower Yukon Delta will move northwest tonight
over St Lawrence Island and the Bering Strait and west of the Gulf
of Anadyr by Monday morning. A second shortwave that lies from
the low in the Central Bering Sea southeast over Sand Point this
afternoon will move north to lie over Nunivak Island and the Gulf
of Alaska Coast by Monday morning, moving north to the Brooks
Range by late Monday night, and over the Arctic by Tuesday
morning. At 850 hpa...Warmer air pushing with some patches of
above zero temperatures moving into the southern interior Monday
night through Tuesday night before cooling back down. Over the
remainder of the area temperatures will rise to -10 or warmer
before starting to cool on Wednesday.

Surface...High pressure continues over the Yukon Territory and
the Upper Tanana Valley with a 1046 mb center near Watson Lake
YT. A broad area of low pressure has moved over most of mainland
Alaska with a 973 mb low near the Pribilof Islands. Over the
Arctic High pressure is building east with a 1034 mb center moving
over the Central Arctic tonight. Leeside troughing north of the
Alaska Range will weaken this evening. A weather front will move
west over the Bering Strait and St Lawrence Island tonight and
tight pressure gradient will persist over the Eastern Bering Sea,
Bering Strait, and Chukchi Sea tonight, but weaken. A weather
front south of the Gulf of Alaska will move north to the Gulf
Coast Monday morning, and move into the interior Tuesday. A very
tight pressure gradient will develop across the Alaska Range as a
strong leeside trough develops to the north. Leeside trough
develops north of the Brooks Range Monday with a 1014 mb low
developing and moving over the Prudhoe Bay by Tuesday afternoon at
1000 mb. As the leeside troughing develops north of the Brooks
Range a ridge of high pressure will build in to the south and a
tight pressure gradient will develop across the Eastern Brooks
Range Tuesday through Wednesday morning.

Arctic Coast and Brooks Range...Mostly cloudy to Cloudy, patchy
fog, flurries, and winds turning onshore for most areas at 5 to 15
mph. For the Northwest Coast winds will be offshore and
increasing as the pressure gradient across the Chukchi Sea and
Western Arctic is squeezed, this will create some issues with
blowing snow so will maintain the current Winter Weather Advisory.
Wind picking up on the Eastern Arctic Coast Monday night will
create some issues around Kaktovik with Strong gusty winds and
blowing snow. Temperatures a bit warmer tonight and tomorrow then
cooling the remainder of the week.

West Coast and Western Interior...Continues to be the most active
area with Blizzard and near Blizzard conditions across the area.
Winds will be diminishing overnight, as will the snow, so look for
improving conditions tonight. Will maintain the current set of
Warnings and Advisories as timing looks good. The next system
moving north into the area Monday night will bring a new set of
issues as the warmer air being pulled north brings to potential
for freezing precipitation in the lower Yukon Delta and southern
Norton Sound Regions. Tight pressure gradient across the western
Alaska Range will produce strong southeast winds gusting to around
55 mph Tuesday near passes.

Central and Eastern Interior...Mostly cloudy conditions will
continue, but there will be some breaks. Temperatures warming.
Strong gap winds and Tanana Valley Jet winds diminishing this
evening, but they return Tuesday morning and will be even stronger
with gusts near 80 mph as a weather front moves across the area.
No significant precipitation expected with the front south of the
Yukon River, with snow developing north of the Yukon Tuesday.

&&

Coastal Hazards for days 3 and 4...None.

&&

Extended Forecast for days 4 to 7...Models are in a bit better
agreement building ridging aloft north of the Alaska Range with a
broad trough over the Western Bering Sea. At the surface a deep
low will move into the Central Bering Sea with a front moving to
the West Coast Friday. A blend of the Ensembles means and the
ECMWF deterministic solution will be used for this forecast cycle.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...

Blizzard Warning for AKZ213.

Winter Weather Advisory for AKZ201-AKZ207-AKZ211.

Heavy Freezing Spray Warning for PKZ210-PKZ220-PKZ225.

Gale Warning for PKZ200-PKZ210-PKZ225-PKZ230.

Small Craft Advisory for PKZ220.

Brisk Wind Advisory for PKZ215-PKZ240-PKZ245.

&&

SDB DEC 17