753
FXAK69 PAFG 291431
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
631 AM AKDT Fri Aug 29 2025

Updated synopsis, key messages, and extended discussion

.SYNOPSIS...

Gusty southerly winds will continue through Isabel Pass and Delta
junction until later this morning, ending as a cold front sweeps
in from the west and causes winds to shift. This same front is
bringing areas of rain and showers to much of the Central and
Eastern Interior, and this rain will shift east through the day as
the front moves through. In its wake, gusty winds will be possible
across the Interior this afternoon. Further west, a coastal system
will move in late tonight and will bring additional rainfall and
southerly winds to the West Coast, with a chance for high surf
conditions. On the North Slope, snow continues through tonight,
with up to a few inches of mostly wet snow possible from Utqiagvik
west.

&&

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

 - Southerly wind gusts up to 60 mph through Isabel Pass and Delta
   Junction will diminish by late this morning. Strong south winds
   continue until the cold front passage today.

 - Chinook flow continues ahead of a cold front that is tracking
   east across the Interior. Rain will shift east with the front,
   with breezy west-southwest winds up to 35 mph and cooler
   temperatures in its wake.

 - Heavy rain is expected on the southern slopes of the Alaska
   Range ahead of the cold front passage with heavy snow above
   ~9000 ft.

 - Except for a few peeks of clear skies Friday evening through
   Saturday morning, skies will be mostly cloudy, with chances
   for light rain showers later on Saturday into Sunday.

West Coast and Western Interior...

 - Spotty light showers will remain possible across the area today
   in the wake of a cold front. A system moving in from the Bering
   will spread steady rain chances northeast along the West Coast
   from late tonight through Saturday.

 - Rainfall totals through Saturday afternoon primarily stay below
   0.5", but coastal portions and higher elevations of the Seward
   Pen and YK Delta and southern slopes of the Brooks Range up to
   1".

 - A coastal system brings a sustained period of southerly winds
   to the coast that may result in another High Surf Advisory and
   continued rain chances Saturday into early next week.

North Slope and Brooks Range...

 - Up to 3 inches of wet snowfall and a thin glaze of ice is also
   possible on elevated surfaces. Light accumulations of snowfall
   have been observed on grassy and elevated surfaces over parts
   of the Arctic Coast, ranging from Utqiagvik west to Point Lay.
   Additional accumulations are possible but will be hindered by
   relatively warm ground temperatures and daytime surface
   heating.

 - West winds up to 30 to 40 mph, with higher gusts, will be
   possible over the eastern Arctic Coast Friday night into
   Saturday as a low moves offshore. Winds of 20 to 30 mph will be
   possible from west of Point Thomson to Nuiqsut during this same
   time frame.

&&

EXTENDED FORECAST DAYS 4-7...

Wet conditions will continue across Northern Alaska, with a
coastal system early next week bringing extensive rainfall to the
West Coast and Western Interior Monday, potentially shifting east
in the Central and Eastern Interior through Tuesday afternoon.
Up to another 0.5 to 1 inches of rain are possible across most of
the Western Interior, with higher totals of 1 to 1.5 inches over
the southern slopes of the western Brooks Range and in the Upper
Kuskokwim Valley. Southerly winds over the Bering will also make a
return. While a warm day is possible over the Eastern Interior on
Monday with a weak/low-amplitude ridge poking in from Canada,
most weather otherwise looks cloudy and near-normal.

&&

.PREV DISCUSSION... /issued 331 PM AKDT Thu Aug 28 2025/

FORECAST ANALYSIS AND DISCUSSION...

The primary short term hazards continue to be strong south winds
through the Alaska Range gaps and wintry mixed precipitation across
the North Slope. The secondary hazards are associated with heavy
rain that fell over the past few days with a pulse of floodwater
moving downstream along the Koyukuk and Kobuk Rivers. These hazards
are associated with a seasonably strong low pressure currently near
Kotzebue at ~996 mb. A deformation zone sets up across the northwest
Arctic Coast tonight into Friday with moderate precipitation rates
that may be high enough to temporarily overwhelm warm ground
temperatures, particularly overnight. As a result, there may be a
few inches of wet snow accumulation between Point Lay, Utqiagvik,
and adjacent interior portions of the western North Slope. This
system drags a seasonably strong cold front across the state tonight
through Friday with falling temperatures (non-diurnal) behind the
front. Gusty west-southwest winds develop behind the front due to
steep low level lapse rates aided by modest cold air advection aloft
atop warm/wet soils across the interior. EFI guidance is
highlighting unseasonably strong winds across most of interior
Alaska on Friday afternoon and evening with wind gusts possibly
reaching toward Wind Advisory criteria. A brief period of calmer
weather and surface ridging moves across the interior on Saturday,
but the reprieve is is brief with the upper level pattern amplifying
again late this weekend. Upper level ridging builds across much of
Alaska early next week with persistent south-southwest flow becoming
established across the West Coast and western interior through early
next week. Fortunately rainfall amounts appear considerably lighter
than what fell earlier this week and warmer/drier conditions may
become similarly established across the eastern interior.

FIRE WEATHER...

The Upper Tanana Valley remains relatively dry with warmer and drier
conditions than the rest of northern Alaska. Temperatures remain in
the upper 60s to low 70s with min RHs in the mid 30% range through
early next week. There aren`t many chances for rain, but a front
Friday afternoon into Saturday may bring a few showers. Strong south
winds continue through the Alaska Range passes, particularly the
area between Isabel Pass and Delta Junction where gusts up to 75
mph are possible through this evening. These winds gradually
diminish ahead of the front then ending quickly behind the frontal
passage. Otherwise, no thunderstorms are expected.

HYDROLOGY...

A flood watch remains in effect for the Kobuk, Koyukuk and Noatak
Valleys through Friday. A flood advisory is in effect for Kobuk and
Allakaket as water levels remain high. Lighter rainfall will
continue in the Western Interior and especially the higher
elevations of the Western Brooks Range where up to 1.25" of rain is
possible along the south facing slopes through Friday night.
Additional rainfall is expected late this weekend into early next
week, but early forecast information indicates lighter rainfall
amounts than what fell earlier this week.

Recent heavy rainfall results in elevated water levels persisting
into the weekend. Keep up to date with all hydro needs at
weather.gov/afg and weather.gov/aprfc.

Coastal Hazard Potential Days 3 and 4...

Persistent southerly winds ahead of the next Bering Sea storm may
result in high surf and water levels of 2-4 ft above normal high
tides starting Saturday night and continuing into early next week.

&&

.EXTENDED FORECAST DAYS 4-7...
Coastal Hazard Potential Days 3 and 4...None


&&

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...Wind Advisory for AKZ837-849-850.
     Flood Watch for AKZ813-814-819-828-831.
     Wind Advisory for AKZ833-834-838>846.
PK...Small Craft Advisory for PKZ803-807-856.
     Small Craft Advisory for PKZ804.
     Small Craft Advisory for PKZ805-806-813-853.
     Small Craft Advisory for PKZ808-855.
     Small Craft Advisory for PKZ809.
     Small Craft Advisory for PKZ810-859.
     Small Craft Advisory for PKZ814-815-860-861.
     Small Craft Advisory for PKZ852.
&&

$$

DS