Winter Weather Advisory 90, NWS Fairbanks, AK

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
318 PM AKDT Wed Sep 22 2021

.SYNOPSIS...
Snowfall with the fist winter storm of the season is tapering off
across the Southeastern Interior. There will be a brief respite
before another system moves into the southeast Interior Thursday
night into Friday bringing additional snowfall. A weather system
has the potential to bring precipitation to the Seward Peninsula
Friday night into Saturday

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.DISCUSSION...
The 22/00 UTC models generally initialized well when compared to
observational data. While the models generally have the same idea
with the synoptic scale pattern there are some differences in the
placement of the precipitation over in the short term. For the
system that will move into the southeastern Interior Thursday
night and Friday, the NAM really keeps the precipitation out of
the Fairbanks area while the GFS and the ECMWF bring some snow
into Fairbanks. The models also differ on the potential for a
system that will affect the Seward Peninsula Friday night into
the Saturday. The GFS and NAM both bring in precipitation while
the ECMWF is different, keeping precipitation out over the ocean.
We really did not change much with the precipitation forecast
today as we thought the inherited grids did a good job
representing things.

Aloft, at 500 mb, a 531 dam low is currently situated over the
lower Yukon Valley, with a trough extending from the low north
into the Beaufort Sea. The trough will dig south tonight merging
with another low moving north through the north Pacific. The
combined low will move into the northern Gulf of Alaska on
Thursday, with the trough pushing inland on Friday. A trough looks
to push into the northwest Arctic Friday night into Saturday.

Central and Eastern Interior...
Snowfall is tapering off across the southeastern Interior this
afternoon after a decent early season snowfall. A handful of
stations reported over 7 inches of total snowfall for this event.
There will be a brief respite before the next system moves into
the southeastern Interior Thursday afternoon into Friday. This
system has the potential to bring 2 to 4 inches of snow to the
parts of the Eastern Interior, with the potential for up to 7
inches in Alaska Range. There is still a lot of model variability
with this system at the moment, resulting in lower confidence in
our overall snowfall forecast to include amounts and timing.
Chances for snow will diminish on early Saturday as the low moves
away. There is also the potential for breezy northerly winds with
this system as well.

North Slope and Brooks Range...
High pressure will continue to build over the area tonight
resulting in winds diminishing and any lingering snow showers
tapering off. With cooler arctic air in place expect increasing
fog and stratus to develop heading toward the weekend. Chances for
snow will increase Friday night and early Saturday as a system
approaches from the south, especially over the eastern half of the
area.

West Coast and Western Interior...
Snow showers will persist over the northern Bering Sea and
Eastern Norton Sound/Yukon Delta into Thursday, mainly along the
coast. Dry northeast winds will kick in over the area which will
promote a dry period for most of the region. The next low of
interest will only impact Saint Lawrence Island with rain or
possibly a rain/snow mix Friday. There is some potential for this
system to bring precipitation to the Seward Peninsula Friday night
into Saturday; however, at the moment there is still model
disagreement.

Extended Forecast Days 4-7...
The models look to show a cooler trend that will persist through
much of the extended period.

Coastal Hazard Potential Days 3 and 4...None.

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.HYDROLOGY...
No concerns at the moment.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...

Small Craft Advisory for PKZ210-PKZ220-PKZ245.
&&

SEP 21