Area Forecast Discussion
Issued by NWS Fairbanks, AK
FXAK69 PAFG 271431
Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
631 AM AKDT THU OCT 27 2016
A strong blocking high centered over the northern Yukon Territory
and northwestern Northwest Territories will rapidly break down
Friday through Friday night as a short wave trough moves eastward
across northern Alaska then weakens over the Yukon Territory
Friday night. Another ridge will begin to build over the western
interior Thursday, becoming a very high amplitude ridge over the
eastern Alaska mainland and southward by noon Friday. The
ridge will gradually narrow while persisting through Sunday.
Strong southwest flow will develop over the Bering Sea tonight
and across the west coast Friday, with a very strong impulse
moving northward up the west coast Friday night through Saturday
The current runs of the GFS/NAM/ECMWF/Canadian models are
coming more into line with the development of a new low
on a strong front moving northward and eastward across the
Bering Sea. At 6 am this morning, models place the front from a
970 mb low near 56N/165E to 56N/173E to 50 nm east of Shemya then
southward and southwestward into the Pacific. By 10 pm this
evening, models are developing a new 970-975 mb low on the front
about 175 nm southwest of St Matthew Island, then deepening the
low to 955-960 mb just west of the Gulf of Anadyr by mid day
Friday. The front is progged to move northward and eastward to St
Lawrence Island-Dall Point and southeastward by early Friday
evening. By late Friday afternoon, the ECMWF/Canadian models are
indicating a second and stronger low, around 965 mb, developing on
the front with the GFS/NAM developing a very sharp trough. GFS
develops an elongated low over the northern Bering Sea Friday
evening which deepens to 962 mb near Wrangel Island by Saturday
afternoon.. All models indicate that the northern and eastern
Bering Sea, the west coast and Chukchi Sea will experience a
period of very strong south to southeast winds as the low moves
northward producing a very strong pressure gradient.
Significant weather expected...
St Lawrence Island...Southeast winds gusting to as high
as 75 mph beginning around midnight tonight and continuing
through mid day Friday. High surf expected on the south
and southeast facing shorelines developing around midnight
tonight and continuing through mid day Friday. Maximum
storm surge of 2 to 3.5 feet expected on the south and
southeast facing shores.
Bering Strait Coast...Southeast winds gusting to as high as 75
mph developing Friday morning and continuing through late Friday
night. High surf conditions expected to develop late Friday
morning and continue through late Friday night. A maximum storm
surge of 4 to 4.5 feet is expected. The greatest risk of high surf
is expected to be along the coast west of Brevig Lagoon which has
exposure to strong southeast winds blowing across a long stretch
of water. Elevated sea levels could cause local minor inundation
anywhere along the coast.
Southern Seward Peninsula Coast...Strong southeast winds
developing late tonight or early Friday morning continuing through
late Friday night before shifting to southwest Saturday morning.
High surf conditions expected west of Topkok from late Friday
morning to midnight Friday night. Maximum storm surge of 3.5 to
4.5 feet is expected. A temporary lull in the storm surge is
expected Saturday morning as the winds shift to southwest and
decrease to around 30 mph. Sea levels are then expected to rise
back to 3 to 5 feet above normal by Sunday evening as the brisk
south to southwest winds persist. This may produce a second period
of high surf conditions. Southeast winds could gust to as high as
60 mph at the peak of the event Friday evening through late Friday
night. A high wind watch or warning may be needed for this area.
Yukon Delta coast...Elevated sea levels are expected along this
stretch of the coast. Sea levels could rise to around 4 feet
above normal at times in the Scammon Bay area which could lead
the possibility of some minor coastal flooding. Subsequent model
runs should be monitored for elevated sea levels along this
stretch of the winds. With the strong winds blowing offshore,
significant wave action is not expected.
Baldwin Peninsula and Selawik Valley...Southeast winds to 55 mph
gusting to 65 mph expected from 6 pm Friday evening to 6 am
Chukchi Sea Coast...Southeast winds increasing Friday morning with
strong winds expected Friday afternoon through Saturday morning.
The strongest winds, 45 to 60 mph with gusts to 75 mph, are
expected to be along the coast north of Cape Krusenstern Friday
night through early Saturday morning.
Precipitation...Rain developing over St Lawrence Island late this
evening, spreading to the Yukon Delta, Norton Sound and the
western Seward Peninsula Friday, and to the remaining west
coast areas Friday night. Rain spreading to the southwest interior
Coastal Hazard Potential...See main discussion.
High Wind Watch for AKZ207-AKZ209.
High Surf Advisory for AKZ211-AKZ213.
High Wind Warning for AKZ213.
Small Craft Advisory for PKZ225.
Storm Warning for PKZ210.
RF OCT 16