Brisk Wind Advisory 12, NWS Fairbanks, AK

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
324 AM AKST Sun Jan 7 2018

.DISCUSSION...

Models...Pretty good agreement all the way around with 07/00Z
solutions, evening into the extended periods over the Arctic.
Surface solutions initialized well against the 07/12Z surface
analysis. With limited precipitation will use the SREF for the
short term. Temperatures have been a real battle the last few
days, but models are in much better agreement, so will use a blend
and make some minor adjustments based on current conditions.

Aloft...At 500 hpa...537 dam high has moved to just north of Point
Lay this morning with the ridge axis extending northwest across
the Arctic and southeast over Yakutat. By Monday morning the
center will be over Point Barrow at 540 dam with the axis
extending north over the high Arctic, and south over Kodiak City.
A 495 dam low that was over the central Bering Sea yesterday has
filled but a trough lies from west of the Gulf of Anadyr southeast
over Sand Point this morning, and there is a 528 dam low over
Kodiak City. The low over Kodiak City will move over the Central
Gulf of Alaska at 528 dam by Monday morning, then merge with a
trough that is moving south over the Yukon Territory and starts
digging southwest over Yakutat Monday evening. The trough over the
Bering Sea will move north up the western flank of the ridge to
lie over the Siberian Coast and Western Chukchi Sea Coast by
Monday morning. Monday the high over Point Barrow will slide
south, then move northwest over the Chukchi Sea while the trough
over the Yukon Territory digs over the Western Gulf of Alaska with
a 516 dam low developing over Yakutat, and over the North Pacific
a 495 dam low will move Over Amchitka then move east over the
Aleutians to Atka by Tuesday afternoon. As the high moves south
then northwest the trough that was over the Siberian Coast will
move up over the top of the ridge to be over MacKenzie Bay by
Wednesday morning with a 520 dam low developing and continuing to
dig south and west as the high persists over the Chukchi Sea. At
850 hpa...Temperatures below zero with the -10 isotherm lying from
Point Lay to Beaver Creek YT this morning and the -20 isotherm
over Demarcation Point. The cold air continues to be pulled
south over the Yukon Territory and the -10 isotherm will move to
lie from Wainwright to Anaktuvuk Pass to Ambler to Galena to
Yakutat, while the -20 isotherm will lie from Kaktovik to Atigun
Pass to Dawson YT Monday morning. The cold air will nudge just a
bit further west through Tuesday morning before it gets pushed
back into Canada Tuesday night.

Surface...Broad area of cyclonic flow around a 980 mb low near
the Gulf of Anadyr persists over the Bering Sea and West Coast
today while high pressure associated with a 1039 mb high 500 nm
north of Point Barrow builds south over mainland Alaska to the
Copper River Basin with a 1027 mb center developing in the
Northern Yukon Territory. High pressure continues to build over
the state as the low in the Bering Sea moves into Siberia and
dissipates. The high in the Arctic will move to 400 nm north of
Prudhoe Bay by Monday morning with a high over the Yukon Territory
building to 1037 mb. A 949 mb low will move to Amchitka by Monday
morning and moves slowly east to Atka by Tuesday afternoon as it
weakens to 973 mb. High pressure will build in south of the
Eastern Brooks Range tonight and tighten the pressure gradient
across the Ray and White Mountains, the Upper Chena and Salcha
Basins, and eventually the Upper Tanana Valley with the Tanana
Valley Jet kicking in. Leeside troughing north of the Brooks Range
will develop Monday as trough builds east across the Plains and
Arctic Coast while high pressure builds west over the south
slopes over the Eastern Brooks Range creating a tight pressure
gradient across the Eastern Brooks Range. The pressure gradient
will also tighten up over the Nulato Hills tonight and persist
through the week.

Arctic Coast and Brooks Range...Ground Blizzard conditions
continue around Point Lay and expect them to continue so no
changes to the Warning and the Winter Weather Advisory for the
Western Brooks Range. GOES MVFR/IFR Probability product at
07/1015Z not showing much low stratus over the Arctic Coast this
morning, and observations confirm that. NPP VIIRS SPoRT 24 hour
Microphysics RGB at 07/1016Z shows a nice patch of stratus over
the Beaufort Sea that is moving southwest toward the Eastern
Arctic Coast and will need to be watched. Most of the area will
be partly cloudy. Northeast to East winds continue across the area
at 10 to 25 mph with winds around 30 to 40 mph around Point Lay.
Blowing snow will continue around the area and visibility may be
impacted more as winds pick up a bit this afternoon. Very poor
visibility will continue around Point Lay into the late afternoon.
Pressure gradient tightens up over the Eastern Brooks Range
Monday with gusty gap winds to 40 mph developing. Temperatures
slightly warmer on the northwest coast, and cooler on the Eastern
Arctic Coast.

West Coast and Western Interior...Decaying front will move north
over parts of the coast today with some light snow or flurries. A
slight chance of freezing drizzle or rain this morning on the
Seward Peninsula. As high pressure builds over the interior it
will push the front off the coast this evening with clearing over
the area. Pressure gradient tightens up over the Nulato Hills
Monday as high pressure builds west and the low moves to the
Aleutians with winds gusting to around 50 mph locally. The low
over the Aleutians Monday will swing a front north over the Lower
Yukon Delta and St Lawrence Island Tuesday with a slight chance of
snow. No significant changes in the coastal temperatures through
Monday, but trending cooler as the offshore flow pulls cooler air
out of the interior.

Central and Eastern Interior...High pressure continue to build
over the area. Mostly clear conditions will continue, but there is
some patchy stratus in the Upper Yukon Flats and Valley, and
Upper Tanana Valley. NPP VIIRS SPoRT 24 hour Microphysics RGB at
07/1016Z shows the stratus appears to be expanding to the west out
of the Yukon Territory and will need to be watched as the flow
around the high may continue to spread it into the Eastern
Interior. The pressure gradient tightens over the Ray and White
Mountains, and Upper Chena and Salcha Basins with gusting winds
increasing later today and continuing into Tuesday at higher
elevations. As the low moves to the Aleutians the leeside trough
enhances north of the Alaska Range and the Tanana Valley Jet will
kick back in with gusty winds starting Monday night and continuing
into Wednesday. Temperatures will continue to fall as cold air
filters in from the east with the coldest temperatures Wednesday
and Thursday morning falling to the 30s below to around 40 below.

&&

Coastal Hazards for days 3 and 4...None.

&&

Extended Forecast for days 4 to 7...Temperature forecast remains
difficult, but models are in better agreement on continued cooling
in the Interior. A upper level low will move over the Upper Yukon
Flats Wednesday night that may spread some clouds into the area,
otherwise mostly clear conditions through the week. Models are in
fairly good agreement so a blend of the current solutions with the
ensemble mean should provide a good start.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...

Blizzard Warning for AKZ201.

Winter Weather Advisory for AKZ205-AKZ211.

Small Craft Advisory for PKZ210.

Gale Warning for PKZ225-PKZ230.

Brisk Wind Advisory for PKZ215-PKZ220-PKZ235-PKZ240-PKZ245.

&&

SDB JAN 18