High Surf Advisory 20, NWS Fairbanks, AK

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
604 AM AKST Thu Nov 9 2017

.DISCUSSION...
Very active weather pattern over northern Alaska continues.

The 00z model suite initialized well against the 00z surface
analysis and verified well against the 06z surface analysis.
There was minimal spread between model families and from the
previous model run in the short and well as the mid range. The
models exhibit reasonable spread in the long range and are
indicating an Omega block developing over the Western Bering Sea
next week which would bring a significantly colder airmass over
northern Alaska.

Aloft at 500 HPA, a 498 DM low 250 nm northwest of Wrangel Island
anchors a longwave trough which continues to spin shortwaves east
and northeast over the northern Bering Sea, through the Bering
Strait, over Kotzebue Sound and into the western Interior. A
strong shortwave currently along a Point Hope to Kotzebue to
Galena line continues to move east and northeast through the day
today. Moist southwest flow ahead of the trough and moist westerly
flow behind the trough will produce ample snowfall in the western
and central Brooks Range as well as the Nulato Hills. Winter
Storm warnings for snow and blowing snow remain in effect for
these areas. Behind the trough 850 mb temperatures drop to 10
below and with brisk westerly winds over the relatively warm
waters of Norton Sound are producing Sea Effect snow showers some
of which will produce locally heavy snow and low visibility as
they move inland today. Nome Radar continues to indicate the
showers moving east south east over Norton Sound. A Winter
Weather Advisories remain in effect for zone 218 with favored
upslope flow from the southwest piling up 4 to 8 inches of snow
along and west of the Dalton Highway. Snowfall ahead of the
surface low over Kotzebue Sound will produce 4 to 7 inches of snow
in zone 219 today mainly north of Indian Mountain. Lighter snow
generally in the 1 to 3 inch range is expected today over much of
the interior.

Ongoing coastal flood event continues along the west coast
especially in Norton Sound where water levels are currently over 7
feet above Mean Low Low Water Levels in Unalakleet. Persistent
and prolonged westerly gale force winds will continue to pile
water up in Norton Sound, the Bering Strait as well as the Yukon
River Delta and adjacent Coast lines. Ongoing Coastal Flood
Warnings and Advisories are valid through this afternoon and
evening. Winds remain strong over the area and will likely extend
how long elevated water levels remain especially in eastern Norton
Sound.

High Surf Advisories remain for zone 207 through noon north of
Kivalina where tide levels remain over 3 feet above normal at Red
Dog Mine Dock and onshore winds continue to push breaking waves
on shore through early this afternoon. High Surf Advisories also
remain in effect for the Northwest Coast where water levels are
around 2 feet above normal tide levels in Barrow. Winds are
expected to go from offshore to along shore later this morning and
onshore tonight. Will need to monitor closely as elevated water
levels and onshore winds may produce high wave run up along the
coast into Friday.

Focus quickly turns to a significant storm system progged to
develop over the southern Chukchi sea Saturday and Sunday and into
northwest Alaska. The track and strength of this storm has the
potential to produce coastal flooding in Kotzebue Sound as well as
along the northern Seward Peninsula especially near Shishmaref.
The storm also has the potential to bring significant snow, and
blowing snow over much of the interior. Continue to monitor.

Coastal Hazard Potential Days 3 and 4... Models continue to show
a strong low moving across the southern Chukchi Sea Saturday and
Sunday and into northwest Alaska. This will low will bring strong
west to northwest winds of 25 to 40 mph gusting to 55 mph to the
Chukchi Sea Coast, and Kotzebue Sound. The strong winds will
produce waves to 20 ft in the Chuckchi Sea and 12 ft in outer
Kotzebue Sound. There is some ice in Kotzebue Sound, but it will
not be enough to provide any protection during this event.
Confidence is increasing that there will be Coastal Flooding in
Kotzebue Sound and around Shishmaref.

&&

Extended forecast for days 4 to 8...
Models continue to indicate a significant winter storm will move
into the state from the northwest spreading heavy snow, gusty
winds, blowing snow to much of the forecast area Saturday and
Sunday. Latest models however now track the storm southeast over
the western interior instead of tracking the low east over the
Brooks Range. This track would reduce the amount of wind
experienced over the central interior however the track would
still produce significant snowfall over the interior. The latest
models continue to indicate a much cooler airmass will move in over
the state next week.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
High Surf Advisory for AKZ201-AKZ202-AKZ207.

Coastal Flood Watch for AKZ202-AKZ207-AKZ209.

Coastal Flood Advisory for AKZ212-AKZ213-AKZ214.

Winter Weather Advisory for AKZ205-AKZ206-AKZ211-AKZ218-AKZ219.

Coastal Flood Warning for AKZ211.

Winter Storm Warning for AKZ212-AKZ217.

Small Craft Advisory for PKZ200-PKZ210-PKZ215-PKZ225-PKZ230-
PKZ235.

Heavy Freezing Spray Warning for PKZ210-PKZ215-PKZ220-PKZ225-
PKZ230-PKZ235-PKZ240.

Brisk Wind Advisory for PKZ245.
&&

CCC NOV 17