580
FXAK69 PAFG 180010
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
410 PM 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 70 mph.

-Heavy precipitation is expected to continue in the Central Interior
Monday morning through Tuesday morning. Expect 24 hour accumulations
of up to 2 inches at higher elevations along the Koyukuk and Dalton
Highway Summits, as well as for places like Tanana and Hughes.
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 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. High
temperatures remain more moderate for the foreseeable future.

West Coast and Western Interior...
-Heavy rainfall is expected 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.

-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.
 Temperatures remain on the cooler side for the rest of the week.

-Northerly wind gusts remain elevated in the Bering Strait on
Tuesday, with gusts up to 35 mph possible. Wind gusts diminish on
Wednesday to 15 kt.

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.

-High temperatures will be in the mid 40s/mid 50s over the plains
and in the mid/upper 30s along the coast through most of the week,
before increasing to the upper 50s/lower 60s on Thursday.


&&

.SYNOPSIS...
A broad area of troughing over Northern Alaska continues to produce
a wide variety of impacts. For the Central and Western Interior,
alongside areas south of the Brooks Range moderate to heavy rain
will fall through Tuesday as a front within a broader decaying area
of troughing stalls, bringing upwards of 1 to 3 inches of rain
before finally dissipating. Meanwhile, strong downsloping winds in
the eastern Alaska Range have brought gusty conditions and kept
drier weather lingering for locations in the Forty Mile Country.
Chances of thunderstorms meanwhile linger across parts of the
eastern Interior, including the Yukon Flats.
Chances of rain will linger through the week, though showers in the
eastern interior will be less widespread and more isolated in
nature. Another system arriving late in the week will bring another
round of widespread rain and breezy conditions to the west coast and
the Bering, before potentially moving inland through the weekend.

&&

.SHORT TERM /THROUGH THURSDAY/...
An active pattern continues across northern AK through Tuesday,
although a short-lived ridge building in on Wednesday will diminish
rainfall chances to some extent. Satellite and radar imagery as of
the time of writing show a broad area of troughing stretching
along a SW to NE axis between St. Paul island and the northern
Yukon. The broad area of troughing is bringing with it a wide
variety of weather. Moderate to heavy rainfall across parts of
the central and western Interior will continue through Tuesday
morning, before chances of rain slowly diminish. Atmospheric
return Intervals of 5-10 years for some locations will be
reflected in precip totals of 2-3 inches for some of these
places before the current system winds down. Chances of rain are
also present across much of the North Slope and the eastern
interior, though rainfall totals for these areas will be
substantially lower as more isolated showers and thunderstorms
are expected. Along the West Coast, a marine layer will attempt
to push back in for some areas overnight into Tuesday, driven by
strong northerly flow through the Bering Strait.

CAPE values in the Yukon Flats and parts of the Brooks Range are
reaching model progged values of 400 to 600 J/KG through Monday
evening. This has fueled the development of isolated thunderstorms,
some of which look to have produced breezy conditions, plenty of
lightning, and periods of moderate to heavy rainfall.

The last big story has been the wind gusts across the eastern Alaska
Range. Chinook winds, driven by the presence of fairly respectable
pressure gradient of 5 to 7 mb across the Alaska Range, have
resulted in wind gusts as high as 70 mph for Isabel Pass, with other
locations seeing wind gusts approaching 60. Winds are currently on a
slow downward trend, and look set to continue that diminishing trend
through the evening and overnight hours into Tuesday.

Through the day on Tuesday, overall precip coverage and strength
will diminish as the trough weakens, though chances of thunderstorms
remain across parts of the eastern interior and the Brooks Range. On
Wednesday, a ridge briefly begins to build across the interior,
which will keep chances of drier weather for the east, even as an
old front keeps precip chances for the north slope, and a shortwave
brings chances of more widespread rain back in for Southwest Alaska.


&&

.LONG TERM /Thursday through Sunday/...On Thursday, weather
should lull briefly as weak troughing over Western Alaska will lead
to persistent, light showers in the Western Interior. Weak ridging
over Canada will lead to warmer and drier, but still moderate,
weather in the Central and Eastern Interior as maximum temperatures
should remain in the 60s. The North Slope will be cooler than the
Interior, but not as wet as Western Alaska.

More impactful weather arrives later in the week as another
widespread rain event is expected for the West Coast. The exact
timing is uncertain with this system, as deterministic models seem
to waver between the bulk of rain arriving overnight Thursday and
Friday afternoon. Ensemble models and clustering support the band of
rain arriving Friday morning, but it`s something we`ll want to keep
an eye on as the event gets closer. 48-hour rainfall totals for
Friday and Saturday along the West Coast currently range between
half an inch to an inch. Winds along along the coast will be strong
along with the rain. Gusts up to 40 mph through the Bering Strait
are possible on the rear side of the system. St Lawrence Island and
the YK Delta Coast are also prime candidates for strong wind gusts,
but remain slightly weaker for now. After the initial impact in
Western Alaska, rain, winds, and cooler temperatures will continue
east into the Interior, although to a lesser extent. Southerly gap
winds through the Alaska Range are expected to swell Saturday
morning before the concensus of models drop the low southeast into
the Gulf of Alaska.

Coastal Hazard Potential... No coastal hazards are expected through
the week.

&&

.FIRE WEATHER...
Warm and dry conditions with temperatures well into the 70s and RHs
below critical thresholds continue in the southeastern Interior;
southerly downsloping winds across the Alaska Range are drying out
the air considerably in these areas while also enhancing diurnal
warming. A Red Flag Warning has been issued for the Upper Tanana
Valley through 7 PM Monday evening for a combination of gusty
southerly winds, warm temperatures, and dry conditions. A fire
(Mukluk) has already developed in this area in the vicinity of Tok.
Through Isabel Pass and into the Delta Junction area, gusty winds,
potentially over 50 mph at times, will be possible through around
midnight tonight but are not likely to fully drop off until late
Tuesday morning. Elsewhere in the Central and Eastern Interior,
cooler conditions in the 50s and 60s with RHs above 40% prevail,
with isolated thunderstorms occurring and expected to continue near
the eastern border through this evening. In Western Alaska and parts
of the Central Interior, it is conversely very wet as a low moving
inland brings extensive rain and showers with wetting rains to the
area. The exception is from near Kotzebue northward, where
temperatures are above 70F in spots, although RHs are still over 40%.

By early Tuesday morning, rain (largely wetting) will overspread
most of the Middle Tanana Valley (including Fairbanks) and the Yukon
Flats, with highs dropping into the low 60s or upper 50s in most
areas. The exception will be the Upper Tanana Valley, which will
remain mostly dry. Some rain/showers and cooler conditions will also
take hold in the Northwestern Interior, ending the streak of warm
conditions there the past few days. By the late morning, southerly
flow across the Alaska Range will largely end, with moister RHs
favored in the Upper Tanana Valley than today. Temperatures are also
expected to drop to near or below 70F in these areas, although
minimum RHs could still fall into the 30s in some areas. By Tuesday
night, while numerous to widespread rainshowers could continue west
of Bettles/north of Tanana, they will become sparser and more
isolated in coverage elsewhere.

From Wednesday onward, temperatures could recover slightly in the
Eastern Interior, with most areas rising back into the mid to upper
60s, with temps around 70 possible in the Upper Tanana Valley, where
RHs in the 30s will be possible. Highs in the inland North Slope
will briefly fall into the 40s and 50s before recovering into the
60s on Thursday. By the late week, there is a signal for further
rain moving into Western Alaska and later the Interior with another
coastal low.


&&

.HYDROLOGY...
Some river rises are expected across the central interior and the
Brooks Range, as a stalled front delivers 5-10 year ARIs (2-3 inches
of rain) through Tuesday. However, previously low existing stream
conditions should prevent any flooding, although a few rivers could
reach bankfull. An ESF has been issued which discusses the river
rises in additional detail.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...Red Flag Warning until 7 PM AKDT this evening for AKZ936.
     High Wind Warning until midnight AKDT tonight for AKZ849.
MARINE...Small Craft Advisory until 6 PM AKDT Tuesday for PKZ806-807.
     Small Craft Advisory from 4 AM to 10 AM AKDT Tuesday for
     PKZ808.
     Small Craft Advisory until 1 AM AKDT Tuesday for PKZ810.
     Small Craft Advisory until 7 PM AKDT this evening for PKZ811.
     Small Craft Advisory from 10 PM this evening to 1 AM AKDT
     Tuesday for PKZ817.
     Small Craft Advisory from 10 PM this evening to 4 AM AKDT
     Tuesday for PKZ853.
     Small Craft Advisory until 10 AM AKDT Tuesday for PKZ854.
     Small Craft Advisory until 1 PM AKDT Tuesday for PKZ856.
&&

$$

SHORT TERM...SPANN
SYNOPSIS...SPANN
LONG TERM...TROYKE
FIRE WEATHER...SALTZMAN
HYDROLOGY...SPANN/BEST