Gale Warning 24, NWS Fairbanks, AK

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
450 PM AKST Sat Feb 29 2020

.SYNOPSIS...
A strong low in the southeast Bering Sea will move NE across
Alaska mainland tonight through Mon. This will bring blizzard
conditions to the Yukon Delta tonight and Sun, heavy snow to the
Southwest Interior tonight through Sun night, and 4-6 inches of
snow to the Eastern Interior south of the Yukon River from Sun
through Mon. This will also bring heavy snow to the south slopes
of the Alaska Range tonight through Mon, with strong south winds
and blowing snow through passes tonight through Sun morning.

Temperatures will warm over the Interior tonight through Sun, then
cool slightly Mon, with a stronger cooling on Tue. Expect well
below normal temps over Northern Alaska Tue through next weekend.

Aloft...
A deep long wave trough stretches from the Canadian Archipelago
across northwest Alaska into the Bering Sea will progress east
over Mainland Alaska by Mon and then remain in place through next
weekend.

A strong short wave trough in the SE Bering will move over SW
Mainland of AK on Sun, then over the SE INterior on Mon, and east
of the Alcan Border Mon night. Heavy snow will spread northeast
over SW Alaska tonight and Sun, and then over the SE Interior Sun
through Mon.

A strong short wave north of Eastern Russia will move over NW
Alaska Mon, and over SW Alaska on Tue. This will bring flurries
and much colder temps to he North Slope and Western AK Mon, and
to the Interior on Tue.

850 MB temperatures range from -10C over the YK Delta and Alaska
range to -24C along and north of the Brooks Range.. Temps will
warm a few degrees over the SE Interior through Sun, while temps
will fall a few degrees Sun over the Brooks Range, North Slope and
West Coast on Sun. All areas will see significant cooling on Mon
and Tue. This will result in warm up at surface south of the Yukon
River, with night times lows much less extreme, while day times
highs will see a light rise. Then will see cooling Mon and Tue,
with temps returning to well below normal by Tue night all areas
and remain cold through next weekend.

Surface...

A 1005 mb low near Wainwright will move to Demarcation Point as a
1002 mb low by 3am Sun, then continue east. Light snow and fog
along and east of this low will spread east across the Arctic
Coast tonight. Snow will taper off to flurries west of this low.
Expect SW winds 15-20 kt just south of this low to spread east
across the Arctic Coast tonight.

A strong low in the Southeast Bering Sea will move to near
Sparrevohn as a 981 mb low by 3pm Sun, and then to the Eastern
Alaska Range as a 989 mb low by 3pm Mon. An occluded front that
lies from this low to King Salmon will move to Bethel to the Kenai
Pen by 3am Sun, to Sparrevohn to Eagle by 3pm Sun, to Denali to
Old Crow by 3am Mon, to Delta Junction to Eagle by 3pm Mon, then
east of the Alcan Border Mon night. Heavy snow will spread north
with this front over SW Alaska tonight and then become moderate
snow over the southern Interior on Sun, and spread to the SE
INterior on Mon, then taper off over the SE Interior Mon night.
Also expect north winds 25-35kt over the West Coast tonight,
causing blowing snow in zones 213 212, and blizzard conditions in
zone 214, before winds decrease on Sun PM. This will cause 6-12
inches of snow over the SW Interior tonight through Sun night,
6-12 inches over S Slopes of the Alaska Range tonight through
Mon, and 4-6 inches across the SE Interior south of the Yukon
River Sun into Mon. This will also cause strong south winds
through Alaska Range Passes late tonight through Sun AM, and could
cause strong winds along the Alaska Highway from Tanacross to Dot
Lake from late tonight through Sun Noon.

High pressure building over the INterior west of the front Mon
will cause NW winds 15-25 mph and blowing snow along the Alaska
Highway Mon, and through Alaska Range Passes. Winds and blowing
snow will decrease on Tue.

&&

.DISCUSSION...
Models verify well aloft and show similar solution through Tue.
Model precip fields show similar areal coverage through through
Tue, and fairly similar amounts. Will use a blend of the ECMF,
GFS, and NAM for precip areal coverage and amounts, for clouds,
and for temps. At the surface at 18Z, models all are 4 mb too
weak on the frontal wave low just west of Utqiagvik, and 4 mb too
weak on the low in the southern Bering. We will adjust by
increasing winds and snow, and slowing eastward movement of front
wave near Utqiagvik. We will also bump up winds along the West
Coast and Western Interior, and slow the incoming movement of the
low and its snow over SW Alaska tonight to account for the deeper
Bering low.

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

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
Wind Chill Advisory for AKZ211.

Winter Storm Warning for AKZ214-AKZ215.

Winter Weather Advisory for AKZ212-AKZ213-AKZ216-AKZ221-AKZ222-
AKZ225-AKZ226-AKZ227.

Gale Warning for PKZ210.

Brisk Wind Advisory for PKZ200-PKZ210-PKZ225.
&&

JB FEB 20