Gale Warning 58, NWS Fairbanks, AK

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
430 AM AKDT Tue Jul 17 2018

.SYNOPSIS...
Aloft...
A progressive westerly flow pattern will persist through Fri with
a ridge building over mainland Alaska on the weekend. Westerly
flow will keep the Northern Interior, North Slope, and Northwest
Alaska wet through late this week, with a warming and drying trend
over the weekend.

A strong short wave trough from Deadhorse to Denali will move to
Demarcation Point to Delta Junction by 4pm Tue, and east of the
Alcan Border tonight. Widespread showers east of this trough will
diminish to isolated showers along and west of the trough.

A second strong short wave over the New Siberian Islands will move
to the western Chukchi Sea by 4am Wed, over the eastern Chukchi
Sea by 4pm Wed, and over the Beaufort Sea and North Slope by 4am
Thu. This will bring rain and gale force winds to NW Alaska and
the North Slope. More in this in the surface section below.

Surface...
A cold front from Old Crow to Northway will move east of the Alcan
Border by noon Tue. Will see west winds and rain along the front
that will taper off west of the front.

A ridge of high pressure over the West Coast of Alaska and Western
North Slope will build east over the Interior and eastern North
Slope by 4pm Tue and then move over the Interior and Beaufort Sea
tonight. Will see showers and widns diminishing under this ridge.

A 992 mb low 500NM southwest of Wrangel Island will move near
Wrangel Island as a 990 mb low by 4PM Tue, to 300 NM northwest of
Barrow as a 988 mb low by 4am Wed, to 450 NM north of Nuiqsut as
a 984 mb low by 4pm Wed, and to 500 NM north of Deadhorse as a 980
mb low by 4am Thu, and to 600 NM north of Demarcation Point by 4pm
Thu. A warm front stretching southeast of the low will move over
NW Alaska by 4pm Tue, to Umiat north by 4am Wed, and from Old Crow
north by 4pm Wed. Rain and fog will spread east along the warm
front. Also expect south-southwest winds 20-30 kt along the warm
front.

A cold front trailing the low will move to the central Chukchi
Sea by 4am Wed, to Deadhorse to Point Hope by 4pm Wed, to
Demarcation Point to Point Hope by 4am Thu, and to lie along the
Brooks Range by 4pm Thu. Expect southwest winds 25-35kt along the
cold front turning west 20 kt west of the front. Rain and fog east
of the cold front to the warm front will taper off west of the
cold front. Expect 0.25 to 0.75 inch of rain over the North Slope
and NW Alaska, heaviest in upslope areas.

&&

.DISCUSSION...
Model initialization has significant uncertainty over western
Alaska and Northeast Russia due to lack of any RAOBs in those
areas. Models start to see differences in speed of incoming short
wave energy over the Arctic Coast Tue PM, with the ECMF bringing
short wave energy in faster than the GFS and NAM, and the ECMF
also moving the surface low on a track further north than the GFS
and NAM Tue night and Wed. At this time favor the faster ECMF
solution due to the strong dynamics involved causing the low to
move northeast at a high speed. The ECMF is not as strong with the
winds over NW Alaska Tue night and Wed as a result of the low
being further north. As a nod to the uncertainty, we will bump
winds up slightly from what the EMCF displays to account for the
uncertainty and potential hazard of the winds.

Coastal Hazard Potential...
High surf expected between Point Lay and Wainwright Tue night
through Wed, and from Kivalina and Point Hope tonight and Wed.
Due to short fetch length and duration, and the peak winds
occuring in the warm sector, expect surge heights of 2-3 feet.
This should cause high surf but no flooding.
The area north of Wainwright is mainly ice covered which will
inhibit and high surf from occuring.

&&

.FIRE WEATHER...
Warmer and drier Wed and Thu across the Interior, with
temperatures warming further through the weekend. RH remaining
above 30% through Fri.

&&

.HYDROLOGY...
No issues.

&&

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

Small Craft Advisory for PKZ210-PKZ220-PKZ225.

Gale Warning for PKZ220-PKZ225-PKZ230.

Brisk Wind Advisory for PKZ235.
&&

JB JUL 18