FXAK69 PAFG 200041
Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
441 PM AKDT Mon Mar 19 2018
A progressive southwest flow with several strong short waves
moving through it is now over northern Alaska. This flow will turn
northwest as a ridge builds over Western Alaska Tue and Wed, with
a blocking ridge developing by Thu and then remaining into the
weekend. This means that warmer and wetter than normal conditions
now over most of Northern AK will become drier and cooler than
normal by Wed under the ridge aloft, then remain cooler than
normal through the weekend.
Short waves have surface fronts/low pressure systems associated
with them and the weather with each will be addressed under the
surface sections below.
A 1010 mb low near Point Lay will move to near Wainwright as a
1031 mb low by 4pm Tue, to 300 nm Northeast of Barter Island as a
1033 mb low by 4am Wed, then continue east. An occluded front from
this low to Deadhorse to Northway will move to Barrow to Inuvik to
Mayo by 4am Tue. Snow with 1-2 inches accumulation accompany this
front. Blowing snow, and west winds gusting 30-40 mph are
occuring with this front over the southeast Interior. Winds, snow
and blowing snow will tapering off by midnight tonight.
A surface trough extending from the Point Lay low to the Bering
Strait will move to Barrow to Nome by 4pm Tue, and to Barter
Island to Denali by 4am Wed, and to Inuvik to Tok by 4pm Wed.
Expect light snow showers or flurries with the trough, and
clearing west of the trough.
A 1010 mb low near St Lawrence Island will move to Kaltag as a
1019 mb low by 4am Tue and to near Talkeetna as a 1026 mb low by
4pm Tue. Several bands of snow showers extend southeast from this
low and can expect 2-4 inches of snow in the area near the track
of the low. Southwest winds 25 kt are occuring in the southeast
quadrant of this low with Gale force winds near the Yukon Delta.
Winds will turn NW 15-25 kt west of the low. Winds will decrease
as the low moves inland early Tue.
A strong low developing in western Bering Sea Wed will move to
the northern Bering Sea Thu. A warm front associated with this
will move into the Central Bering Sea by 4am Wed, to the Chukotsk
Peninsula to the Yukon Delta by 4pm Wed, then spreading north Wed
night. This will bring snow, blowing snow, and a chance of rain
with the front to the West Coast Wed into Thu. At this time still
much uncertainty as to precipitation amounts, type, and
An associated cold front will move into the Eastern Bering Thu
bringing SE gales to the eastern Bering.
Models similar solutions through 4pm Wed at h500, h700, h850,
pcpn. On Wed night and Thu the ECMF keeps the precip further west
of Nome than the GFS and NAM. At this point, Wed night and Thu is
worth a chance of precip at Nome, but great uncertainty about
amounts so keeping amounts lower than GFS/NAM at Nome Wed night
and Thu. At the surface, the ECMF verifies much better than the
NAM/GFS at 18Z today on the low just southwest of Gambell. On
other features the models initialize similarly. The ECMF solution
which keeps this feature deeper than other models through tonight
is best. This means that winds along the west coast will be a bit
stronger than NAM/GFS would indicate, and precip may be stronger
All models agree on block setting up Thu, but then diverge from
each other. I would lean closer to the ECMF solution of a REX
type block with the high over the Arctic and Low moving east
across northern AK over the weekend, then the ridge rebuilding
over N AK next week. This means generally clear and cold
conditions over the Interior and Arctic Coast will develop late
this week and continue into next week.
Coastal Hazard Potential Days 3 and 4...SE Gales Thu but expect no
issues in zone 213 due to ice cover extending south of St Lawrence
Winter Weather Advisory for AKZ212-AKZ213-AKZ214-AKZ219-AKZ220-
Gale Warning for PKZ210.
Brisk Wind Advisory for PKZ200.
JB MAR 18