Area Forecast Discussion
Issued by NWS Fairbanks, AK
FXAK69 PAFG 270002
Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
402 PM AKDT WED OCT 26 2016
Main focus is ongoing active weather pattern in the Bering Strait
for the latter half of this week.
Morning 12Z analysis continues to show large scale
troughing/cyclonic flow over eastern Siberia and the western
Bering Sea, with short wave ridging and a closed high at 553 dm
over eastern mainland Alaska. At the surface, 970 mb low was seen
over eastern Siberia, or around 450 miles west of Wrangel Island.
A 988 mb low was seen near Attu Island. Broad high pressure was
seen over the Canadian Archipelago extending southward into
western Canada and eastern Alaska.
Models are in fair to good agreement on the overall synoptic
situation through the weekend, with fair agreement over the larger
scale features this into early next week. Large scale cyclonic
flow will remain anchored over eastern Siberia and western Bering
Sea through the remainder of the week, with high amplitude ridging
downstream over far western Canada and eastern Alaska. A 502 dm
upper low over the Kamchatka Peninsula will shift over the western
Bering Sea by early Friday at 495 dm, before spinning north into
eastern Siberia Friday night. A 965 mb low over northern Siberia
will drift further west and gradually weaken tonight. Low pressure
will develop over the western Bering Strait to around 970 mb 150
miles northwest of Attu Island by 4 am Thursday, and around 964 mb
420 miles west of St Lawrence Island by 12Z Saturday, drifting
northward into eastern Siberia by Saturday evening. A strong
weather front will move northward through the Bering Sea Thursday
night into Friday.
West coast and west interior:
Winds: Issued a High Wind Warning for Zone 213 in effect until
late Friday night. A shortwave trough moving northward through the
Bering Strait has helped tighten up the gradient over the Bering
Sea, resulting in warning level winds over the Bering Strait coast
this afternoon. These are expected to subside this evening as the
disturbance lifts northward. Strong storm force winds will then
accompany the next front that will lift through the area late
Thursday night into early Friday, likely sustained between 45 to
55 mph with gusts as high as 70 mph over St Lawrence Island and
the Bering Strait coast. A High Wind Watch has been issued over
the portion of zone 207 for the Point Hope area for similar
strength winds, to occur from late Friday afternoon through
Saturday morning. Elsewhere along the west coast southeast winds
are expected to be around 30 to 50 mph with the frontal passage.
The ECMWF and Canadian guidance has been suggesting a wave of low
pressure at around 960 mb developing along the front and swinging
northward through the Bering Strait Friday night. While this would
suggest stronger winds for more of the west coast, opted to go
with the GFS/NAM deterministic solutions which depict the
pressure pattern with the front as an open trough rather than a
stronger closed low; which is more consistent with the ensemble
means of the GEFS and NAEFS. Winds will gradually subside on
Surge: A storm surge of 3 to 5 feet above tidal levels is expected
over St Lawrence island, the Bering Strait coast, the southern
Seward Peninsula and Yukon Delta late Thursday night into Friday.
Given the fast moving nature of this front and associated winds,
expecting another round of high surf and possible beach
erosion/minor coastal flooding for these areas as opposed more
major coastal flooding.
Precipitation: Another round of moderate to at times heavy rain
will swing over the west coast with the weather front Friday
evening, with the precipitation weakening as the front pushes
inland. In addition, several inches of snow is expected to fall
in the upper Kobuk and Noatak Valleys, as well as the western
Brooks Range Friday night into Saturday.
North Slope: Relatively quiet weather expected for this area for
the next several days with the next chance of any snow coming
Saturday as the weather front pushes east. Winds look to remain
relatively light until the east winds increase as the weather front
pushes north of Bering Strait.
Interior: High pressure will continue to bring fair weather to
much of the central and eastern Interior through Friday. Expecting
some stratus to continue to develop and move into the Fortymile
and upper Tanana Valley tonight into early Thursday. The decaying
weather front will bring a chance of snow to the central Interior
by Saturday. Temperatures look to remain near or slightly above
seasonal averages due to deep mid and upper level southerly flow.
Will have to watch the potential for gap flow through Alaska Range
passes late Friday night into Saturday.
High Wind Watch for AKZ207.
High Wind Warning for AKZ213.
Gale Warning for PKZ210-PKZ220-PKZ225.
NTS OCT 16