294
FXAK69 PAFG 031349
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
549 AM AKDT Thu Sep 3 2026

.SYNOPSIS... An active weather pattern continues across
northern Alaska as an atmospheric river with multiple embedded
systems moves up from the Southwest. Periods of widespread
moderate to heavy rainfall are anticipated, along with breezy
conditions. While some breaks are expected in between systems,
the potential for additional waves of precipitation will
continue through much of next week. Temperatures will be on an
overall warming trend through the weekend, as SW flow brings
high temperatures back into the 60s for much of the central
interior by Sunday.


.KEY MESSAGES...
Central and Eastern Interior...

- After a chilly Thursday morning, minimum temperatures
  moderate back into the 40s for Thursday night, and remain more
  moderate through the weekend.

- Southwesterly flow into the Interior later this week with this
  system will lead to warming temperatures, as highs climb into
  the 50s/60s to near 70F for the Upper Tanana Valley starting
  Friday.

- Rain moves in from southwest to northeast through the day Thursday
  as a warm front tracks northwards into the region.

- An atmospheric river behind the front will bring additional rainfall
  Thursday night into Friday with another system bringing an
  addition round of steadier rain Friday night into Saturday.

- Expected rainfall amounts Thursday through Saturday are around
  0.50 to as much as 2.00 inches for the Central Interior west
  of and including FNSB, and 0.25 to 0.75 inches east of FNSB. The
  exception to these amounts will be in the Upper Tanana Valley
  and Fortymile region, where conditions are expected to remain
  dry due to downsloping flow.

West Coast and Western Interior...

- Rainfall coverage diminishes along the West Coast through the
  afternoon hours on Thursday as an atmospheric river moves
  East. Parts of the Western interior will continue to see
  periods of moderate rainfall through Saturday.

- Expected rainfall amounts through Thursday night shows around
  0.50 to 1.00 inches across Western Alaska, with locally
  higher totals at St. Lawrence Island up to around 1.25 inches.

- Winds increase out of the E/SE, shifting to the S/SW late
  Thursday into Friday as winds lessen. Peaks wind gusts are
  expected to be around 30 to 50 mph across the West Coast
  (strongest at St. Lawrence Island) and 20 to 40 mph for the
  Western Interior.

- Southerly winds over the Bering will continue to push large volumes
  of water towards Alaska`s West coast late Thursday through
  Saturday, especially for the Yukon Coast as well as the Norton
  Sound. High surf is possible in this area, with water levels
  potentially reaching 2 to 4 feet above the normal high tide,
  highest around Golovin and Elim.

North Slope and Brooks Range...

- Scattered rain and snow showers for the east across far
  Northern Alaska through Thursday, with light additional
  snowfall accumulations favoring the Brooks Range.

- A Bering Sea low will send a warm front into far northern
  Alaska late Thursday and Friday, with widespread light
  precipitation for the Brooks Range, and scattered showers for
  the north slope.

- Temperatures will hold steady through the first half of the
  weekend, with highs in the 30s/40s and lows in the 20s/30s.
  High elevations of the Brooks Range tonight could drop to
  around 10-20F with wind chills down around 0-10F.

- Expected precipitation amounts late Thursday into Friday are
  expected to be around 0.1 to 0.50 inches in the Brooks Range,
  and a trace to 0.10 inches across the Arctic Coast/Plains.
  Light snow is also expected in the Brooks Range and Arctic
  Plains just north of the higher terrain.

&&

.SHORT TERM /THROUGH MONDAY/...

Satellite and radar imagery show the active weather pattern in full
swing as of the time of writing. Widespread rainfall has
arrived along the West Coast, as a low begins to form along the
intersection between a warm front and an atmospheric river, both
of which are steadily moving up from the SW and beginning to
overrun the area.

The pattern is being driven by three primary ingredients. To the
east, a ridge over the Gulf will continue to persist, only
slowly moving off to the E through the weekend. This will
help to push systems away from southeast (and to a lesser extent
southcentral) AK and instead redirect them through the
interior. To the west, a slow moving occluding low in the Bering
Sea has thrown a warm front up and into the area. And moving up
from the south and threading the needle between the low to the
west and the ridge to the east, an atmospheric river, is
following the warm front up into northern Alaska.

The initial warm front, which has been slowly pushing north through
Norton Sound during the early morning hours on Thursday, will
be superseded by the atmospheric River moving up from the
subtropics through the day on Thursday. This atmospheric river
has associated PWAT values of up to 1.5 inches and looks set to
bring a surge of moisture across the central and western
interior through Thursday. Chances of rain will begin reaching
the wider Fairbanks area by late Thursday morning, with
widespread rainfall expected by late Thursday afternoon, if not
sooner. With a still lingering ridge over the Gulf of AK slowing
any eastward movement of the atmospheric river, anticipate
periods of widespread rainfall to continue through Saturday. Two
particularly prominent shortwaves embedded within the larger
moisture plume, one arriving on Friday and one moving through on
Saturday morning, will offer especially enhanced rainfall
potential. The chance of a few thunderstorms across the central
and eastern interior can`t be ruled out either on Saturday,
although these will be very isolated in nature. While the
atmospheric river will largely be cut off by the second
shortwave, chances of rainfall will continue to linger, driven
this time by the still extant low over the Bering and its own
embedded waves, although past Saturday the day-to-day totals
will be significantly lower.

Given the subtropical origins of the atmospheric river arriving on
Thursday, the atmospheric column will be saturated up through ~500
mb over areas that it passes through. The forecast leans towards
more aggressive precipitation totals as a result, with QPF values
through Saturday likely closer to the NBM 75th percentile or even
higher, than to the NBM mean. Consequently, 2-5 year 48 hour average
recurrence intervals across parts of the central and western
interior, with river rises anticipated. For additional
information, refer to the hydrology section of the forecast.

Fortunately, the threat of any significant coastal flooding remains
on the low end. The distance of the low in the Bering from the
mainland will help limit Sustained surface winds around the
vicinity of the western coast. This will put a cap on any
coastal flood potential, and instead high surf advisories have
been issued for parts of the coast along Norton Sound where wind
directions are most favorable for some locations to see beach
erosion.


.LONG TERM /MONDAY THROUGH WEDNESDAY/...

The active weather pattern continues through the first half of next
week, albeit with lower overall precip totals past Saturday.
The ridge over the Gulf of AK will be displaced E into British
Columbia through Sunday and Monday, opening the door for more a
broad area of troughing across the area. Within this area of
troughing, multiple shortwaves and remnant fronts (associated
with the now all but dead low in the northern Bering), continue
to bring moisture to northern AK. Ensembles have started to hone
in on a new potential 990-1000 mb coastal low in particular
which could move up from the SW and bring elevated winds and
waves to the west coast. At this time, ensembles have not yet
pinned down the low`s landfall location, with anywhere from the
Seward Peninsula to the Alaska Peninsula currently possible. A
low track further south would result in fewer impacts for the
West Coast, while a low track further north could open up the
potential for some beach erosion. Stay tuned for updates.

Coastal Hazard Potential...

little change in the forecast since previously. A Bering Sea low and
associated warm front will move into Western Alaska through
Thursday, with widespread rain and gusty winds expected. Water
levels could rise 2 to 4 feet above the normal high tide line in the
Norton Sound, and 1 to 2 feet above the normal high tide line along
the Yukon Delta Coast. Water levels are expected to peak late
Thursday into Friday and Saturday morning. Gusty east to southeast
winds Wednesday into Thursday will shift to the south to southwest
Thursday into Friday, leading to more onshore flow and the potential
for higher water levels. As a result we have issued a High Surf
Advisory for coastal areas of the eastern Norton Sound where
guidance is showing the highest water level rises at this time.

&&

.FIRE WEATHER...
Thursday, we will be transitioning from a cold, dry, polar air mass
to a warm, wet, tropical air mass. Temperatures in the southeast
Interior will be climbing from below freezing Thursday morning to
near 60 degrees Thursday afternoon. Winds will become southerly on
Thursday and increase in strength through the Alaska Range Thursday
evening. Due to unfavorable direction, winds through Windy and
Isabel pass should stay below 50 mph at their peak Thursday night.
More generally, winds in the Tanana Valley should peak around 10 to
15 mph each afternoon. Lowest RHs should be in the Upper Tanana
Valley Thursday afternoon before wetter air arrives. Relative
humidity may get as low as 35%.

Continuing into the weekend, maximum temperatures will climb in to
the upper 60s on Friday, before settling into the low to mid 60s
Saturday and Sunday. Overnight lows will remain above freezing,
around 40F. Despite a significant amount of moisture coming into the
Interior, the southwest angle means there is little chance for
meaningful rain in the Upper Tanana Valley. Still, RH will be more
moderate, between 45 and 55%.


&&

.HYDROLOGY...
A strong push of moisture across the Western and Central Interior is
expected over the next couple of days. Rainfall totals of 1 to 2.5
inches between Fairbanks, Bettles, and McGrath will be possible so
expect fairly decent rises in local streams and rivers with sandbars
potentially covered. Exact location of these higher amounts remain
uncertain as ensemble members show a wide range of totals due to
varying storm tracks, but models are currently showing the area of
heaviest rainfall in the lower Tanana River Basin and the middle
Yukon. Given the anticipated saturation of the atmospheric column,
think that the more aggressive model runs are likely to be closer to
accurate regarding precip totals, with 2-5 year 48 hour ARIs likely
for parts of the central and western interiors, and isolated patches
of close to 10 years not out of the question.


&&

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...High Surf Advisory from 10 PM this evening to 11 AM AKDT
     Saturday for AKZ822-824.
MARINE...Small Craft Advisory until 1 PM AKDT this afternoon for PKZ801-
     802-805-852-853.
     Small Craft Advisory until 4 PM AKDT this afternoon for PKZ806-
     854.
     Small Craft Advisory until 1 AM AKDT Friday for PKZ807-856.
     Small Craft Advisory from 10 AM this morning to 1 AM AKDT
     Friday for PKZ808-809-855.
     Small Craft Advisory from 1 PM this afternoon to 1 AM AKDT
     Friday for PKZ810.
     Small Craft Advisory from 4 PM this afternoon to 6 AM AKDT
     Friday for PKZ811-857.
     Small Craft Advisory from 7 PM this evening to 6 AM AKDT
     Friday for PKZ812-858.
     Small Craft Advisory until 10 AM AKDT this morning for PKZ816-
     817-850.
     Gale Warning until 7 AM AKDT this morning for PKZ817.
     Small Craft Advisory until 7 AM AKDT this morning for PKZ851.
&&

$$

KEY MESSAGES...Spann
SYNOPSIS.......Spann
SHORT TERM.....Spann
LONG TERM......Spann
COASTAL........Laney
FIRE WEATHER...Troyke
HYDROLOGY......Lewis/Spann