799
FXAK69 PAFG 011440
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
640 AM AKDT Sat Jun 1 2024

.SYNOPSIS...A very pleasant summer Saturday is expected across the
Interior today with temperatures rising into the upper 60s to mid
70s under mostly sunny skies. Thunderstorms will be more limited
today except in the Upper Koyukuk Valley this afternoon. Sunday
will bring more in the way of showers and thunderstorms as a
strong shortwave trough moves west across the Interior. Out west,
Gale force winds will blow through the Bering Strait through at
least Monday with near freezing temperatures. Accumulating snow is
likely through the Central Brooks Range and north to the Arctic
Coast tonight through Monday.

&&

.DISCUSSION...

Analysis and Model Discussion...Mainland Alaska remains
sandwiched in between a number of upper level lows. This will
bring continued showery conditions to most of northern Alaska. At
500 mb, a 527 dam low lies north of Prudhoe Bay with a 522 dam low
in the Bering Sea and a 532 dam low in the Gulf of Alaska. These
lows will largely remain in place until early Sunday morning when
the low in the Arctic dives south as a cutoff low feature,
reaching the Yukon Delta by Tuesday morning. This setup combined
with high pressure over the western Chukchi Sea will bring strong
to Gale force northerly winds through the Bering Strait. As this
low dives south on Sunday morning, a strong shortwave trough will
move into the central and eastern Interior from the east. Models
have sped this feature up significantly over the past 24 hours,
now showing it moving through the Fairbanks area before peak
heating and forming a convergence zone with moisture being
advected northward by the low diving south. This should move the
focus of heavy showers and thunderstorms to be from the Lower
Yukon northeast to Tanana to near Arctic Village on Sunday
afternoon. Precipitation will fall across the Brooks Range and
North Slope as well, with accumulating snow expected from Atigun
to Anaktuvuk Pass across the North Slope and north to Prudhoe Bay.
With the low moving south through early next week, this opens the
door for additional shortwave troughs from the east to bring
heavy showers and thunderstorms to the central and eastern
Interior.

Models are in excellent agreement, especially considering how
complex this pattern is with numerous shortwaves. We will use a
blend of models for the forecast today. We will follow the model
trends and speed up the precipitation associated with the
shortwave on Sunday and make minor tweaks to the winds through the
Bering Strait and through Alaska Range Passes.

West Coast and Western Interior...Summer conditions are expected
today across most of the area except through the Bering Strait
where north winds will increase to Gale force and freezing
temperatures will persist. These winds will likely persist through
Tuesday as a deep Arctic trough drops south over the area. This
will bring cooler temperatures through early next week.
Thunderstorm chances will be greatest today across the Upper Kobuk
Valley as remnant shortwave energy from yesterday continues to
move through the area.

Central and Eastern Interior...Warm and sunny conditions are
expected beneath a building ridge. Isolated thunderstorms will be
mainly confined to higher terrain and much more isolated today
than the past few days. On Sunday a shortwave trough from the east
will bring a round of locally heavy showers and widely scattered
thunderstorms along with slightly cooler temperatures. The area of
focus for precipitation and thunderstorms looks to be from Nikolai to
Manley Hot Springs and north along the Elliott and Dalton Highway
corridor. Precipitation amounts could approach one half inch in
areas that see the strongest storms and/or multiple storms. Monday
will bring more showers and thunderstorms, with the wetter pattern
continuing through much of next week.

North Slope and Brooks Range...Areas of freezing fog continue this
morning along the Arctic Coast and inland across the Arctic
plains. Light snow is expected starting tonight in the Central
Brooks Range as an Arctic trough digs south. A more well defined
convergence zone will develop on Sunday, bringing heavier snowfall
to the Central Brooks Range and accumulating snow as far north as
the Arctic Coast. Expect 2 to 4 inches of snow from Anaktuvuk Pass
to Sag DOT Camp, about 2 inches north of there to the Arctic
Coast, and up to 6 inches over Atigun Pass.

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

&&

.FIRE WEATHER...Near Red Flag conditions are expected today across
the Middle Tanana Valley and Yukon Flats with high temperatures
approaching 75 degrees and minimum relative humidities dropping
into the 20 to 25 percent range. Expecting winds to remain below
15 mph though. Widely scattered thunderstorms are still expected
northeast of Huslia today as shortwave energy from yesterday
remains. Across the rest of the Interior, thunderstorm activity
will be lower beneath a ridge building in from the northeast.

On Sunday, a shortwave trough from the east will cause increased
thunderstorm activity as well as locally heavy showers. The focus
of the thunderstorms looks to be from Nikolai to Manley Hot
Springs and north along the Elliott and Dalton Highway corridor.
Temperatures will be cooler and RHs a bit wetter on Sunday.
Additional shortwaves from the east embedded in a very persistent
pattern will bring more showers and thunderstorms into next week.

&&

.HYDROLOGY...The water level in Fort Yukon will continue
receding very slowly. Satellites and ground observations continue
to indicate abundant snow in the Porcupine Mountains. As
temperatures warm this week, snowmelt could lead to continued high
water along the Porcupine and the interrelated sloughs.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...None.
PK...Small Craft Advisory for PKZ801-802.
     Small Craft Advisory for PKZ805.
     Gale Warning for PKZ806.
     Gale Warning for PKZ807.
     Brisk Wind Advisory for PKZ808.
     Brisk Wind Advisory for PKZ810.
     Small Craft Advisory for PKZ811-816-817-850-851-857.
     Small Craft Advisory for PKZ812-853.
     Gale Warning for PKZ854.
     Gale Warning for PKZ856.
     Small Craft Advisory for PKZ858.
&&

$$

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