Winter Storm Warning 29, NWS Fairbanks, AK

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
319 PM AKDT Mon Apr 15 2024

.SYNOPSIS...
Active weather pattern continues across Northern Alaska as a
series of storms move east northeast. A low pressure system
causing strong southerly winds, snow, and blowing snow from the
Bering Strait north to Point Hope this afternoon with conditions
improving tonight. A second system is approaching the Y-K Delta
and will move north along the West Coast through Tuesday. Strong
southerly winds, heavy snow, and blowing snow are expected to
develop over the West Coast as the low moves north.

&&

.DISCUSSION...
Synoptic Analysis and Forecast...
Aloft, at 500 mb, a 482 dam (decameter) low sits near the North
Pole. Broad upper level troughing extends southwest from this
low and across eastern Russia and into the Bering Sea with a
shortwave stretching across Wrangel Island and Chukotka. This
shortwave absorbs the energy from the wave moving north of St
Matthew this evening and tonight. The shortwave slowly pushes east
through Tuesday with the trough axis stretching from the low to
Wrangel Island across the Gulf of Anadyr to east of Atka and south
into the far North Pacific. A closed upper level low develops
over the Gulf of Anadyr Tuesday afternoon, dropping south in to
the Bering Wednesday. A 558 dam ridge is over the central Gulf of
Alaska with the ridge axis stretching north to Glenallen to Circle
to Mackenzie Bay. The ridge axis pushes east Tuesday to stretch
from near Yakutat and into the Yukon and Northwest Territories. By
Wednesday a 567 dam ridge center sets up over the southern Yukon
with the ridge becoming negatively tilted by Thursday.

At the surface, a 996 mb low is near the North Pole. A 1003 mb low
is 125 NM north of Utqiagvik with a front extending east over the
offshore Arctic waters a front stretching southwest to the
northeast Chukotsk Peninsula. This low and front quickly lifts
northeast through tonight as the low moves to be 350 NM north of
Kaktovik by Tuesday morning and then continuing northeast,with a
front extending southwest to the northwest Arctic Coast. A 992 mb
low 75 NM southeast of St Matthew Island moves northeast to be
centered over the Bering Strait Tuesday morning weakening to 996
mb further weakening as it cross the northwest Arctic coast and
then moves offshore north of Utqiagvik by Tuesday afternoon,
resulting in an elongated trough/front that stretches from near
the western Canadian Archipelago southwest to Point Hope and then
south along the West Coast. By Wednesday, this front/trough
stretches across the eastern Arctic waters to the Seward Peninsula
and then south to the Aleutians. High pressure builds east across
the Arctic Waters Wednesday and Thursday.

Models...
The 15/12Z models initialized well against the 12Z RAOBS and
surface obs and are in good agreement with the overall synoptic
pattern. Differences really don’t emerge until Tuesday night into
Wednesday with the upper level low that develops over the Gulf of
Anadyr that drops south into the Bering Sea. Models are well
clustered in terms of strength but vary in placement with the GFS
the farthest west and fastest to move south. Made only very minor
changes to the inherited forecast package as it was in good shape
and leaned towards a general model blend for the last twenty four
hours.

North Slope and Brooks Range...
A low moving northeast off the Chukotsk Peninsula is dragging a
front across the region, bringing snow, blowing snow, and gusty
winds, especially to the northwest and western Arctic coast. South
to southwest winds increase to 20 to 35 mph for the western and
northwest Arctic coasts with gusts to 50 near Point Hope. At
Utqiagvik winds have been gusting into the 30 mph range. Blowing
snow has been reduced visibility to half a mile or less across
these areas. Conditions expected to improve late this evening and
tonight. Further east, drier conditions are expected and south to
southwest winds of 15 to 25 mph will prevail. In the Brooks Range,
southerly flow ramps up Monday into Tuesday with sustained winds
of 20 to 30 mph and gusts of 40 to 50 mph. These southerly winds
will cause areas of blowing snow reducing visibility to one half
mile or less through Tuesday evening.

West Coast and Western Interior...
Strong southerly winds, snow, and blowing snow are ongoing this
afternoon, as two systems impact the West Coast. The northernmost
system is impacting the area from the Bering Strait coast, the
Chukchi Sea coast and the Noatak Valley. Wind gusts of 30 to 50
mph have been reported, as well as periodic blizzard conditions
and heavy snow. The second storm system is approaching the Y-K
Delta this afternoon, where Chevak has dropped in visibility to a
quarter mile or less with wind gusts of 40 to 50 mph. Strong
southerly winds will spread north tonight and Tuesday with gusts
up to 50 mph expected from the Seward Peninsula south. Areas of
blowing snow will accompany these winds dropping visibility to a
quarter mile or less along the Y-K Delta and the southern Seward
Peninsula, and a half mile or less at times elsewhere along the
coast. Some rain may mix in with the snow. Heaviest snow
accumulations through Tuesday night of 6 to 12 inches of snow at
Kivalina, Point Hope and Red Dog Mine, as well 6 to 12 inches over
the southern Seward Peninsula from Golovin west. Unsettled
conditions continue through the week.

Sea levels 2-3 feet above normal along the West Coast into Tuesday
could cause water to push on top of the ice near shore.

Central and Eastern Interior...
Fairly quiet conditions across the Central and Eastern Interior
this week as ridging aloft builds in, the exception being the
along the south slopes of the central Brooks Range where falling
combines with gusty southerly winds to produce visibility of half
a mile or less along the Dalton tonight through Tuesday. West to
southwest winds of 15 to 25 mph expected over the Interior summits
through Tuesday. Southerly Chinook flow develops Monday in the
Alaska Range with gusts up to 60 mph expected at this time.
Temperatures trend upwards this week with highs Tuesday in the 30s
north and upper 40s and lower 50s south and highs in the upper
30s north to lower to mid 50s by Wednesday.

Extended Forecast Days 4-7...An Arctic low remains in place in the
high Arctic this week while an upper level ridge axis becomes
situated over the Eastern Interior and the Yukon. An upper level
low develops over the Gulf of Anadyr with troughing extending
south of the Aleutians.

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

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...Winter Storm Warning for AKZ801-825.
     Winter Weather Advisory for AKZ802-803.
     Wind Advisory for AKZ849.
     Winter Weather Advisory for AKZ809-812.
     Winter Storm Warning for AKZ814.
     Winter Weather Advisory for AKZ815.
     Winter Weather Advisory for AKZ817.
     Winter Weather Advisory for AKZ819.
     Winter Storm Warning for AKZ820-821.
     Winter Storm Warning for AKZ822-823.
     Winter Weather Advisory for AKZ824.
     Winter Weather Advisory for AKZ826.
     Winter Weather Advisory for AKZ827.
PK...Gale Warning for PKZ801.
     Gale Warning for PKZ802-850.
     Gale Warning for PKZ803-805-852.
     Gale Warning for PKZ804.
     Gale Warning for PKZ806.
     Brisk Wind Advisory for PKZ807.
     Brisk Wind Advisory for PKZ808-809.
     Gale Warning for PKZ810-855-856.
     Gale Warning for PKZ811-812-857-858.
     Brisk Wind Advisory for PKZ813-814-860.
     Brisk Wind Advisory for PKZ816-817-851-859.
     Brisk Wind Advisory for PKZ816-817.
     Brisk Wind Advisory for PKZ851-859.
     Gale Warning for PKZ853-854.
     Brisk Wind Advisory for PKZ861.
&&