895
FXAK69 PAFG 171309
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
509 AM AKDT Mon Aug 17 2026

.KEY MESSAGES...
Central and Eastern Interior...
-Gusty winds continue through Monday night. A High Wind Warning is
in Effect for Isabel Pass through 12 AM Tuesday for wind gusts up to
75 mph. Wind Advisories are in effect for Delta Junction and Windy
Pass for wind gusts up to 65 mph through 4 PM Monday.

-Heavy precipitation is expected in the Central Interior Monday
morning through Tuesday morning. Expect 24 hour accumulations of up
to 1.75 inches at higher elevations along the Koyukuk and Dalton
Highway Summits. Rainfall remains lighter (<0.25 inches) from
Fairbanks east through Wednesday when post-frontal convective
showers extend into the region, especially over higher terrain.
Chances for an isolated thunderstorm are possible in the White
Mountains Monday afternoon, as well as potentially later in the week.

-Temperatures continue to cool over the next couple of days, with
widespread highs in the upper 50s/low 60s expected in the region
(except for the Upper Tanana Valley, which stays in the upper 60s)
by Wednesday.

West Coast and Western Interior...
-Heavy rainfall is expected Monday into Tuesday for higher
elevations along the Koyukuk, with accumulations up to 2 inches of
rainfall possible between Galena and Huslia by Tuesday morning. This
rain could potentially bring sharp rises along the Koyukuk and
nearby tributaries. No flooding is anticipated, but smaller creeks
and streams could become bankfull.

-After Kotzebue tied a daily record high temperature on Sunday,
temperatures cool off significantly as a front moves through on
Monday evening. Widespread highs will be in the mid 40s/low 50s on
the coast and mid 50s/low 60s inland by Wednesday afternoon.

-Northerly wind gusts increase in the Bering Strait Tuesday into
Wednesday after a front moves through, with gusts up to 55 mph
possible.

North Slope and Brooks Range...
-1-2 inches of precipitation is possible along the southern slopes
of the Central Brooks Range by late Tuesday. This rain could
potentially bring sharp rises along the Koyukuk and nearby
tributaries. No flooding is anticipated, but smaller creeks and
streams could become bankfull. On the north side of the range, areas
in the Eastern Arctic Plains/Coasts could see accumulations between
0.5 inches and 1 inch.

-After high temperatures reached 80 degrees over the Arctic Plains
over the weekend, troughing drops temperatures across the North
Slope to start the week. High temperatures will be in the mid
40s/mid 50s over the plains and in the mid/upper 30s along the coast.

&&

.SYNOPSIS...
An upper level low tracks northeast across the northern half of the
state Monday through Tuesday night. Gap winds continue in both
Alaska Range Passes through Monday Evening/Night, but are stronger
in Isabel Pass. The heaviest precipitation is expected Monday
morning through Tuesday morning at higher elevations along the
Koyukuk. Precipitation is expected to continue over the Eastern
Brooks Range/Arctic Plains/Arctic Coast on Tuesday into Wednesday,
though accumulations are lighter. Weak troughing is expected to
stick around at least for the next week, with cooler and showery
conditions prevailing in Northern Alaska. Unless you`re in the
Southeast Interior, where temperatures stay in the upper 60s with
chances for isolated thunderstorms, conditions are slowly but surely
starting to resemble typical fall weather.

&&

.SHORT TERM /THROUGH THURSDAY NIGHT/...
An upper level low currently centered over the Lower Kuskokwim will
track northeast across the state, bringing rain showers to a swath
of the Interior and North Slope Monday and Tuesday. Models did a
poor job initializing the main low across the board in the 0Z runs
because of its phasing with a weaker low to the southwest. As a
result, the surface low is situated east of its anticipated
location. This resulted in stronger winds in the Alaska Range passes
than anticipated since the pressure gradient in the passes
strengthened. The Wind Advisory was upgraded to a High Wind Warning
over Isabel Pass, with additional Wind Advisories added for Delta
Junction and Windy Pass to account for the stronger gradient.

The upper level low will track northeasterly through the Interior
Monday, bringing a swath of widespread rain showers along with it.
Precipitation totals could reach 2 inches over higher terrain along
the Koyukuk River in between Galena and Huslia Monday morning
through Tuesday morning according to the NBM 75th Percentile, which
performed well regarding the region and magnitude of heaviest
precipitation on Sunday. The Central and Eastern Interior from
Fairbanks east will stay much drier Monday, with totals ranging from
about 0.25 inches in the Middle Tanana Valley to 0 along the Alaska
Highway south of Delta Junction. However, if models continue to
place the surface and upper level lows too far west, the extent of
heavier precipitation could be more eastward than current model
guidance indicates. There is also a chance for isolated
thunderstorms in the White Mountains Monday afternoon as shortwaves
moving over the Alaska Range interact with warmer temperatures at
the surface, especially closer to the border where temperatures are
warmer/cloud cover is more sparse.

The low continues to move northeast on Tuesday, with the heaviest
precipitation expected to fall over the Eastern Brooks Range and
Eastern Arctic Coast/Plains. Since this feature weakens as it moves
over land, precipitation totals drop on Tuesday, with the highest 24
hour totals expected to be around 1 inch between Tuesday and
Wednesday. As the low clears the Interior, post-frontal convection
arrives, finally including the Central and Eastern Interior from
Fairbanks east on Wednesday. Isolated portions of higher terrain in
the Interior could see an additional 1+ inches of rain with post-
frontal convective showers. The cold air advection causing the post-
frontal convection in the Interior will also cause winds along the
Bering Strait to increase Tuesday morning through Wednesday morning.

By Wednesday, temperatures cool down into the 50s/60s in the
Interior and 40s/50s on the North Slope. General troughing is
expected to continue in Northern Alaska after this low moves
through, with no major disturbances expected on Wednesday. A weak
front will clip the North Slope on Wednesday, bringing light rain.
On Thursday, there is potential for ridging to return in the
Southeast Interior. If the ridge is able to build while lingering
energy from the trough is in the region, isolated thunderstorm
activity would be possible in Fortymile Country and the Upper
Tanana Valley Thursday afternoon.

&&

.LONG TERM /FRIDAY THROUGH SUNDAY/...
Looking ahead towards the weekend, an Arctic low will move
southeast from Eastern Siberia and into the Bering Sea. This low
will begin to move south of St. Lawrence Island Friday
afternoon, and by Saturday morning will move onshore along the
West Coast. Ensemble guidance is in good agreement with this
low on its approximate strength of around 996 to 1000 mbs. With
this relatively weak low we are not expecting there to be any
gale force winds over the water and along the coastline. With
weak ridging over the Eastern Interior at this time we could
see some southerly gap winds in the Alaska Range passes begin to
develop.

Later into the weekend there is not a lot of agreement on where
this low will go once it begins to interact with all of the
terrain in the Western Interior and the ridge axis over the
Eastern Interior. If this low is not able to move the ridge
axis out of the way we could see southerly flow make a brief
return giving way to some warmer temperatures across the
Interior. With cooler 850 mb temperatures we would not
anticipate these chinook winds to dramatically warm the
temperatures. If the low does move the ridge axis east, than we
can expect cooler and wetter conditions to continue across the
Northern Alaska into the early parts of next week.

Coastal Hazard Potential...
No Coastal Concerns are anticipated.

&&

.FIRE WEATHER...
Fire weather concerns will be decreasing across much of Northern
Alaska Monday as a sweeping cold front will bring rain showers,
increased cloud cover, and cooler temperatures. In the Eastern
Interior valleys we will struggle to see wetting rains, but once
you get west of Fairbanks wetting rains will become more
widespread. There remains some fire weather concerns in the
Upper Tanana Valley and towards Eagle, as well as the Kobuk
Valley and the Western Brooks Range on Monday. Temperatures will
stay in the low to mid 70s across these regions, but some cloud
cover should help to moderate the minimum RH values.

Going into Tuesday all of the Interior will be in the 50s/60s
with isolated to scattered rain showers. The strongest showers
will be in the Koyukuk Valley and southern slopes of the Brooks
Range. Immediately north of the Alaska Range will continue to
see weak down sloping, but there should be enough lingering
moisture from the passing cold front to keep minimum RHs above
40%.

While troughing is expected to linger for much of the work week,
there are some hints at weak ridging developing in the far
Southeastern Interior Wednesday and Thursday. This could lead
to some slightly warmer temperatures and isolated thunderstorms
in the Upper Tanana Valley and Fortymile Country, particularly
from Northway to Eagle. These thunderstorm chances will heavily
rely on a weak upper-level disturbance moving through the region
during peak heating, and there is not a lot of model agreement
at this time.

&&

.HYDROLOGY...
A Bering Sea storm will be bringing a wet cold front across
Interior Alaska. By late Tuesday 1" to 2" of rainfall will be
possible across the Koyukuk Valley and the southern slopes of
the Central Brooks Range. This rain could potentially bring
sharp rises along the Koyukuk and nearby tributaries. No
flooding is anticipated, but smaller creeks and streams could
become bankfull.

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...Wind Advisory until 4 PM AKDT this afternoon for AKZ837-847.
     High Wind Warning until midnight AKDT tonight for AKZ849.
MARINE...Small Craft Advisory until 6 AM AKDT Tuesday for PKZ806-807-
     854-856.
     Small Craft Advisory from 7 PM this evening to 1 AM AKDT
     Tuesday for PKZ810.
     Small Craft Advisory from 4 PM this afternoon to 10 PM AKDT
     this evening for PKZ811.
     Small Craft Advisory until 10 AM AKDT this morning for PKZ816.
     Small Craft Advisory until 1 AM AKDT Tuesday for PKZ817.
     Small Craft Advisory from 7 PM this evening to 4 AM AKDT
     Tuesday for PKZ853.
&&

$$

KEY MESSAGES...Schlezinger
SYNOPSIS...Schlezinger
SHORT TERM...Schlezinger
LONG TERM...Dennis
FIRE WEATHER...Dennis