Gale Warning 125, NWS Fairbanks, AK

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
247 PM AKDT Thu Nov 2 2017

.SYNOPSIS...
Aloft...
A long wave ridge over the Gulf of Alaska and mainland AK with a
trough over the western Bering and Sea of Okhotsk will persist
through the weekend. This is causing zonal flow with several
strong short waves making their way east across northern AK
through the weekend.

A strong short wave trough along the West Coast of Alaska will
move east into Canada by Fri pm. This supports a cold front and
surface low which is referenced below.

A second and stronger wave over Kamchatka will move along the
West Coast of Alaska Sat and to the Eastern Interior of Alaska
Sun. There will be another round of snow with this feature and it
will be addressed in the surface data below as well.

Surface...
A 1000 mb surface low 300 nm northwest of Barrow will move to 400
nm northeast of Demarcation Point as a 997 mb low by 4am Fri, to
Banks Island as a 997 mb low by 4pm Fri, and then continue moving
east. A cold front stretching south from this low to Prudhoe Bay
to the Bering Strait to St Matthew Island, will move to Inuvik to
Fort Yukon to Bethel to a low in the southern Bering by 4am Fri,
to Beaver Creek to Bethel by 4pm Fri. There will be 2-4 inches of
snow spreading east with the front, with up to 6 inches in higher
terrain of zones 206, 207 217 and 222, and up to 8 inches in zones
225. Will see low visibility in blowing snow zones 203 204 206
and higher terrain 220. Temperatures have warmed above freezing in
zones 201 and 202 so blowing snow unlikely to produce sustained
low visibility, but snow squalls combined with strong winds will
drop visibility low briefly through Fri. West winds 25-35 kt now
occuring along the Arctic Coast with this front. This is causing
High Surf at Barrow that will continue into Fri.

An Arctic cold front extending west from the low will move over
the Arctic Coast Fri and then move east Fri night. Expect west
winds gusting 40-60 mph overs zones 203 204 and 206 near the coast
with this front.

The 1017 mb low moving into the Central Bering at 4pm Fri will
move to 100 nm west of the Bering Strait as a 1008 mb low by 4am
Sat, to 60 nm west of POint Hope as a 1005 mb low by 4pm Sat, to
Buckland as a 1010 mb low by 4am Sun, and to near Denali as a 1018
mb low by 4pm Sun. Expect rain and snow mix along the west coast
with this feature, and then 3-6 inches of snow with it as it moves
east across the Interior, with higher amounts in the Alaska
Range. Expect southeast winds 20-30kt east of the low along the
West Coast Sat, turning northwest 25-35kt on the west side of the
low Sat PM into Sun am. This will cause elevated surf and sea
levels along the West Coast Sat night but at this time looks to be
of 12 hr duration and short fetch so not high surf expected. This
will need to be watched as this is area of strongest model
inconsistency.

&&

.DISCUSSION...
Deterministic models in good agreement through 4am Sat, then
diverge on the location and strength of the low in the Bering
Strait area. At this time prefer the GFS Sat into Sun as it moves
the low back to the southeast and maintains its depth over the
Seward Pen and Norton Sound more than ECMF and NAM. The GFS is
preferred given the strong cold advection supporting this low.

GFS and ECMF similar through Mon, then ECMF builds block while GFS
remains progressive, just like yesterday. We again prefer the
progressive pattern of the GFS over Northern AK as this has been
the trend the past few weeks, and is the norm for this time of
year.

Coastal Hazard Potential Days 3 and 4...
West winds 25-35kt causing high surf at Barrow today through Fri.
East of Point Barrow there appears to be enough ice along the
shore to prevent surf issues along the beach.

Expect southeast winds 20-30kt along the West Coast Sat, turning
northwest 25-35kt Sat PM into Sun am. This will cause elevated
surf and sea levels along the West Coast Sat night into early Sun but
at this time looks to be of 12 hr duration and short fetch so no
high surf expected. This will need to be watched as this is area
of strongest model inconsistency.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
High Surf Advisory for AKZ202.

Winter Storm Warning for AKZ208.

Winter Weather Advisory for AKZ202-AKZ203-AKZ204-AKZ206-AKZ217-
AKZ220-AKZ221-AKZ222-AKZ223-AKZ225.

Small Craft Advisory for PKZ220-PKZ235-PKZ240-PKZ245.

Gale Warning for PKZ225-PKZ230.
&&

JB NOV 17