Heavy Freezing Spray Warning 36, NWS Fairbanks, AK

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
414 PM AKDT Fri Oct 29 2021

.SYNOPSIS...
An Arctic Cold front along the West Coast of Alaska with several
lows along it is causing snow showers and gusty winds along the
West Coast today that will taper off this evening as the lows move
north and weaken.

Significant weather changes are coming to all of Northern Alaska
this weekend as a strong storm in the Western Gulf of Alaska moves
north over Western Alaska Sat and Sun, and then over the Western
North Slope on Mon.

This storm will bring south winds to 80 mph to the Alaska Range
area this weekend, temperatures in the 30s and 40s to the Eastern
Interior, and south winds 40-50 mph to the Brooks Range Sat PM
along with temperatures in the 20s and 30s. This will bring heavy
snow to the Western Interior this weekend, with the 6-12 inches of
snow north and west of Kobuk to Galena to Anvik, while the area
southeast of Kobuk to Galena to Anvik will see 3-6 inches of snow
along with periods of rain and possible freezing rain. The West
Coast will see 3-8 inches east of Kivalina to Golovin.

This storm will bring high surf to the Chukchi Sea Coast from
Shishmaref to Point Hope Sun afternoon through Mon AM with
northwest winds of 20 to 30 mph. This storm will also bring high
surf to the Arctic Coast from Cape Lisburne to Utqiagvik from late
Sun night until late Mon night with southwest winds 25 to 35 mph.
There is the possibility of blizzard conditions with this storm
Sun night and Mon over the Coast from Kivalina to Point Barrow due
to these winds, but there is much uncertainty as to if snow and
if low visibility in blowing snow will occur.

&&

.DISCUSSION...
At 12Z, models verify well aloft. Models show just slight
differences aloft with strength and timing of short wave through
Sun night, but larger differences show up Sun night and Mon. The
NAM and ECMF show faster solutions Sun night and Mon, and are
preferred do the the strong south flow aloft, and strong dynamics
involved. 850 MB temps rise above freezing SE of Kobuk to Galena
to Anvik on Sat, and over the North Slope East of Utqiagvik Sun.
This will bring the chance of rain and freezing rain southeast SE
of Kobuk to Galena to Anvik on Sat into Sun, and E of Utqiagvik
Sun.

With precipitation, models show similar solutions through 12Z
Sat, then the NAM and ECMF are slightly faster than the GFS moving
precip north. By Sat night the GFS pushes the precip further NW
than the NAM and ECMF, and then on Sun the GFS linger the precip
over the West Coast while the NAM and ECMF starting moving the
precip back east. Favor a blend of the NAM and ECMF precip
locations and amounts to reflect the faster movement shown aloft
and at the surface by the NAM and ECMF. This will also affect the
change from snow to rain or freezing rain, and prefer the NAM and
ECMF with the occurrence of than as well.

At the surface as 15Z, models all verify 3-4 mb too weak on the
low north of Point Hope and the low near the Bering Strait. Expect
that to add a few kt to winds along the Chukchi Sea coast and from
Nome West this afternoon/evening. Will likely increase chance of
snow showers in those area this afternoon/early evening as well
until the lows move north and offshore. The strong low developing
in the Western Gulf of Alaska is now having very cold Arctic Air
fed into the west side of it and expect this will cause it to
deepen rapidly today and into tonight. Also, the track of the low
as it moves north Sat and Sun is along the Arctic front and
should continue to feed cold air into the system. For this reason
expect the feature moving north on Sat and Sun may be deeper than
models indicate. The NAM and ECMF move a deeper low north over
Western Alaska than the GFS on Sat night and Sun. The NAM has the
deepest low on Sun into Mon, and for this reason it is preferred
at this time as we expect the feature to be deeper than any models
show. Expect that winds over NW AK will be 3-5 kt stronger Sun
PM into Mon over NW Alaska as that low will likely be deeper than
even the NAM indicates.

Bottom line for models is that we will use a blend of the NAM and
ECMF for temps, precip location and amounts, and clouds, and use
the NAM for winds but increase winds above the NAM over NW AK this
evening and again Sun PM into Mon.

Coastal Hazard Potential Days 3 and 4...
High surf along the Chukchi Sea Coast from Shishmaref to Point
Hope Sun afternoon through Mon AM with northwest winds of 20 to 30
mph.

High surf to the Arctic Coast from Cape Lisburne to Utqiagvik
from late Sun night until late Mon night with southwest winds 30
to 40 mph.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
High Surf Advisory for AKZ201-AKZ202-AKZ207-AKZ209.

Winter Weather Advisory for AKZ206-AKZ216-AKZ219-AKZ220-AKZ227.

Winter Storm Warning for AKZ208-AKZ212-AKZ215-AKZ217.

High Wind Warning for AKZ223-AKZ225-AKZ226-AKZ227.

Heavy Freezing Spray Warning for PKZ210-PKZ220-PKZ230-PKZ235.

Small Craft Advisory for PKZ200-PKZ210-PKZ220.
&&

JB OCT 21