High Wind in Alaska, December 4 to 5, 2017

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
341 PM AKST Sun Dec 3 2017

.DISCUSSION...
An active pattern is expected for the next few days across
northern Alaska. Strong wind are expected on the north side of the
Alaska Range tonight continuing into Monday. Gusty winds are
expected to develop tonight over the summits north and west of
Fairbanks. This combined with falling snow will result in blowing
snow causing poor visibility at times along the Steese, Dalton an
Elliot Highways. Blowing snow is also expected for the areas
south of the Bering Strait on the west coast as winds increase
this evening. Overall the models are in good agreement out through
Monday. Thereafter, the begin to differ on the timing of the main
features.

Aloft, at 500 mb, a ridge along the Canadian border will be
pushed to the east tonight by a 508 dam low that will move from
the Gulf of Alaska into Bristol Bay overnight. As the low move
into Bristol Bay the winds aloft will increase over the Alaska
Range and the Interior. The aforementioned low will move into the
Bering Sea Monday night. For much of the remainder of the week
the pattern aloft will feature the ridge along the Canadian
border with a low in the Bering Sea. Through the course of the
week there will be periods where the southerly flow over the
Alaska Range will increase in strength; however, at this time the
timing of this varies between the models.

At the surface, a 962 mb low south of Port Heiden will move into
Bristol Bay by tonight and by tomorrow afternoon will lie over
the Yukon Delta at 984 mb. This low will move northwest through
the Bering Sea Monday night and Tuesday and by Tuesday afternoon
will be over St. Lawrence Island and by Wednesday morning will be
over the Chukotsk Peninsula. A weak trough just north of the
Brooks range will weaken tonight. A 1035 mb high will persist 79N
149E through Monday before starting to move to the west. A ridge
of high pressure stretches from the high to the Beaufort Sea
Coast of Alaska. This ridge will slide to the west along with the
main high on Monday. This combined with the northwestward moving
low will cause the pressure gradient to tighten up over the
northwest Arctic coast of Alaska Monday night.

Interior: Winds on the north side of the Alaska Range are
expected to increase this evening. This is later than model
guidance was suggesting at this time yesterday. I adjusted the
start time on the ongoing high wind warnings out for zones 223,
225, 226 and 227 back by about 6 hours based on current guidance.
The strongest winds are still expected late tonight/early
tomorrow morning. Winds are also expected to pick up over the
summits in the Interior tonight. A front moving north over
Interior tonight and Monday will bing snow to areas north and west
of Fairbanks. Fairbanks and point south will see little to no
precipitation with this due to strong downslope winds off of the
Alaska Range. With the afternoon package I am issuing Winter
Weather Advisories for zones 219, 220 and 221. In these zones the
combination of falling snow and gusty winds will result in blowing
snow that will make travel difficult at times along the Dalton,
Elliott and Steese Highways (primarily over the summits where
winds will be the strongest). Monday night and Tuesday relatively
dry conditions are expected over the Interior. The southerly flow
will result in a warming trend for Monday. Fairbanks, for
example, will see highs in the upper 20s while points closer to
the Alaska Range could see highs in the low to mid 30s.

West Coast and Western Interior: I made minor adjustments to the
timing of ongoing winter weather advisories that are out for
zones 211, 212, 214 and 215. I also issued an additional winter
weather advisory for zone 216. Winds will northwesterly winds will
increase this evening from the Yukon Delta north to the bering
Strait. This combined with snow that is expected fall tonight will
produce blowing snow that will limit the visibility at times. The
ongoing winter weather advisory for zone 213 looks in good shape.
Winds will pick up there tonight. As the low moves westward over
the Bering Sea winds will turn more southerly on Tuesday This may
produce some high surf for Nome and elsewhere along the southern
Seward Peninsula Coast.

North Slope and Brooks Range: Blowing snow will be the main issue
tonight across the north slope. I issued winter weather advisories
for blowing snow for zones 203 and 204 to go along with the
inherited advisory in zone 201. Winds and blowing snow will slack
off some late monday east of Wainwright. As the low moves
northward in the Bering Sea the pressure gradient will tighten up
on the northwest Arctic Coast Monday evening resulting in
increased winds.

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

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
High Wind Warning for AKZ223-AKZ225-AKZ226-AKZ227.

Winter Weather Advisory for AKZ201-AKZ203-AKZ204-AKZ211-AKZ212-
AKZ213-AKZ214-AKZ215-AKZ216-AKZ219-AKZ220-AKZ221.

Heavy Freezing Spray Warning for PKZ210-PKZ220-PKZ225-PKZ230.

Gale Warning for PKZ225-PKZ230.

Small Craft Advisory for PKZ210-PKZ220.

Brisk Wind Advisory for PKZ200-PKZ235-PKZ240-PKZ245.
&&

DEC 17

Special Weather Statement
National Weather Service Fairbanks AK
901 PM AKST Sun Dec 3 2017

AKZ219>226-041615-
Upper Koyukuk Valley-Yukon Flats and Surrounding Uplands-
Central Interior-Middle Tanana Valley-Deltana and Tanana Flats-
Upper Tanana Valley and the Fortymile Country-Denali-
Eastern Alaska Range-
Including Allakaket, Hughes, Bettles, Caribou Mountain,
Gobblers Knob, Fort Yukon, Venetie, Central, Circle,
Stevens Village, Beaver, Chalkyitsik, Birch Creek,
Circle Hot Springs, Eagle Summit, Twelvemile Summit, Nenana,
Anderson, Tanana, Minto, Manley Hot Springs, Rampart,
Lake Minchumina, Livengood, Fairbanks, Fort Wainwright,
Eielson AFB, Ester, North Pole, Moose Creek, Two Rivers, Fox,
Chatanika, Chena Hot Springs, Sourdough Camp, Salcha,
Delta Junction, Fort Greely, Harding/Birch Lake, Dry Creek,
Dot Lake, Healy Lake, Tok, Tanacross, Eagle, Tetlin, Northway,
Alcan, Chicken, Boundary, Healy, Denali National Park,
Carlo Creek, Kantishna, Mentasta Lake, Black Rapids,
Donnelly Dome, Trims DOT Camp, Eagle Trail, and Mineral Lake
901 PM AKST Sun Dec 3 2017

...Slippery Roads Over The Eastern Interior This Week...

Strong southerly chinook winds blowing over the Alaska Range have
have brought temperatures above freezing to much of the Alaska
Range this evening, along with areas of freezing rain. This will
cause packed snow and ice on roads to become very slippery.

The chinook winds and warm temperatures will spread north to
Fairbanks late tonight and continue into Monday. This will cause
roads in Fairbanks and across the Interior to become more slippery
tonight and Monday. Additionally, the summits of the Elliot,
Steese and Dalton Highways will have blowing snow and low
visibility from tonight through at least Monday.

The southerly flow, warm conditions, and slippery roads are
expected to continue through the week.

JB

Special Weather Statement...CORRECTED
National Weather Service Fairbanks AK
906 PM AKST Sun Dec 3 2017

AKZ219>226-041615-
Upper Koyukuk Valley-Yukon Flats and Surrounding Uplands-
Central Interior-Middle Tanana Valley-Deltana and Tanana Flats-
Upper Tanana Valley and the Fortymile Country-Denali-
Eastern Alaska Range-
Including Allakaket, Hughes, Bettles, Caribou Mountain,
Gobblers Knob, Fort Yukon, Venetie, Central, Circle,
Stevens Village, Beaver, Chalkyitsik, Birch Creek,
Circle Hot Springs, Eagle Summit, Twelvemile Summit, Nenana,
Anderson, Tanana, Minto, Manley Hot Springs, Rampart,
Lake Minchumina, Livengood, Fairbanks, Fort Wainwright,
Eielson AFB, Ester, North Pole, Moose Creek, Two Rivers, Fox,
Chatanika, Chena Hot Springs, Sourdough Camp, Salcha,
Delta Junction, Fort Greely, Harding/Birch Lake, Dry Creek,
Dot Lake, Healy Lake, Tok, Tanacross, Eagle, Tetlin, Northway,
Alcan, Chicken, Boundary, Healy, Denali National Park,
Carlo Creek, Kantishna, Mentasta Lake, Black Rapids,
Donnelly Dome, Trims DOT Camp, Eagle Trail, and Mineral Lake
906 PM AKST Sun Dec 3 2017

...Slippery Roads Over The Eastern Interior This Week...

Strong southerly chinook winds blowing over the Alaska Range have
brought temperatures above freezing to much of the Alaska Range
this evening, along with areas of freezing rain. This will cause
packed snow and ice on roads to become very slippery.

The chinook winds and warm temperatures will spread north to
Fairbanks late tonight and continue into Monday. This will cause
roads in Fairbanks and across the Interior to become more slippery
tonight and Monday. Additionally, the summits of the Elliot,
Steese, and Dalton Highways will have blowing snow and low
visibility from tonight through at least Monday.

The southerly flow, warm conditions, and slippery roads are
expected to continue through the week.

JB