High Surf Advisory 9, NWS Fairbanks, AK

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
154 PM AKST Sun Nov 4 2018

.DISCUSSION...
As advertised for early this week it will be active and stormy
across the Bering Sea and West Coast as multiple systems are
expected. Elsewhere it will be relatively quiet with typical
seasonal weather expected across the central and eastern Interior
portions of Alaska. Although models solutions have become more
aligned in forecast track for in the first in series of low
pressure systems that will move up from Bering Strait, there are
still differences in location of this low pressure that will have
impacts on winds and exact locations for snow. At this time the
NAM appears to be further away from west coast moving north across
Bering Strait whereas the GFS has slightly closer moving into
Norton Sound and north across the Seward Peninsula. The ECMWF was
lagging behind. The GFS winds this morning appeared to be best
initialized, especially with stronger winds. Looking beyond
Tuesday the second stronger low pressure system moving into the
Bering Sea there is still considerable spread remains on Wednesday
and Thursday.

Aloft, at 500 mb, an upper level ridge currently situated over
Northern Alaska will gradually shift east into western Canada
through Wednesday. A strong low over the Gulf of Anadyr will move
into into the western Bering Sea this evening and then will shift
east to be over St Lawrence Island by Tuesday morning. A strong
shortwave out ahead of this main upper low center will move over
the Chukotsk Peninsula tonight into Monday morning. The main low
center will move north over the Bering Strait Tuesday and into the
Chukchi Sea by Tuesday evening.

At the surface, a 1002 mb low over the Bering Strait will move
north and will be over Wrangel Island by Monday morning. A 970 mb
low will move into the western Bering Sea by Monday morning and
will move east to be over St Lawrence Island Tuesday morning as
990 mb, and then will move north over the Bering Strait through
Tuesday night as 1000 mb, reaching the Chukchi Sea by Wednesday
morning as 1007 mb. A second strong low will move into the
western Bering Sea Wednesday morning. A 1025 mb ridge of high
pressure will remain over the Arctic, but will gradually shift
east over the next couple of days to be located northwest of Banks
Island as 1035 mb.

West Coast and Western Interior...The main forecast focus will
be a strong low that is expected to move across the Bering Sea
through early this week and will bring bring a combination of
coastal and winter hazards to the area. Although still some slight
differences in timing, the forecast track for models are coming
more aligned. Although specific details and locations still not
exact can expected south winds up to 30 mph will develop over St
Lawrence Island and Norton Sound ahead of a front tonight into
Monday morning with a lull expected Monday night. A second round
of south to southeast winds 25 to 35 mph will develop early
Tuesday morning as the main low moves closer to St Lawrence
Island. These winds will shift to the southwest as the low moves
into the Chukchi Sea late Tuesday night. Latest model guidance
indicates that an initial round of elevated water levels Norton
Sound is expected Monday with the peak in forecast total water
levels expected by late Tuesday afternoon of 4 to 6 feet. The
combination of higher water levels and winds may result in high
surf over Norton Sound. In additions to high surf concerns there
will be also winter related hazards inland away from coastal
areas as potential for heavy snow and some blowing snow depending
on temperatures. Along the coastal areas south of Bering Strait
will have a wintry mix or rain and snow then as with warmer
southerly moisture pushes northward, temperatures will rise for
rain along the coastal areas. Then inland Seward Peninsula and
areas north of the Bering Strait will see snow. Snowfall amounts
of 3 to 10 inches are possible over Interior Seward Peninsula and
3 to 10 inches over the Kobuk Vally and Lower Noatak Valley
through late Tuesday afternoon. For the Chukchi Sea Coast and
Kotzebue Sound 2 to 4 inches is possible. Have issued Winter Storm
warnings for zones 208, 210, and 217 as snowfall amounts could
exceed warning thresholds in 24 hours, but will just be on the
borderline criteria. There is concern for blowing snow but may not
reduce visibility due to the warmer temperatures.

North Slope and Brooks Range...East to southeast winds 20 to 30
mph will continue across the Arctic Coast through Monday with
strongest winds west of Utqiagvik. Areas of fog have developed in
areas Deadhorse and Nuiqsut that will continue through the
morning. The winds along and east of Utqiagvik will begin to
diminish slightly as the pressure gradient weakens with the
surface low moves northward and Arctic high pressure moves east.
However, along the Chukchi Sea coast will see another round on
increased southerly winds from Point Lay southward starting
Monday night into Tuesday. Could potentially have some light snow
develop for areas west of Utqiagvik that is associated with the
strong Bering Sea low Monday night into Tuesday.

Eastern and Central Interior...Clear with relatively quiet
weather-wise with seasonal temperatures  across the area through
Tuesday. Will see increasing clouds Wednesday as well chance of
showers increasing across central portions of Interior extending
from Bettles to Tanana and over the Alaska Range by Thursday.
Biggest impact for majority of area will be how much cloud cover
impact temperatures and timing.

Coastal Hazard Potential Days 3 and 4...As discussed and
advertised in Western Coast section, the track of this Bering Sea
storm will produce strong south to southwest winds as the storm
approaches and will produce strong westerly winds on the back side
of the storm as the low pressure departs to the north and east.
This could bring elevated water levels, particularly along south
and west facing shorelines south of the Bering Strait including
the Bering Strait, Norton Sound and St Lawrence as well as the
lower Yukon Delta coast on Monday and Tuesday. The timing of the
highest elevated surf appears to be on Tuesday. Residents in
these areas should continue to monitor the developing situation
for the latest forecasts and possible statements. Please see
www.weather.gov/fairbanks for updates and additional details.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
Winter Storm Warning for AKZ208-AKZ210-AKZ217.

Heavy Freezing Spray Warning for PKZ215-PKZ220-PKZ230-PKZ235.

Gale Warning for PKZ230.

Small Craft Advisory for PKZ210-PKZ220-PKZ225-PKZ235.
&&

Nov 18