333
FXAK69 PAFG 240010
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
410 PM AKDT Sat Aug 23 2025

.SYNOPSIS...

An active period of weather continues through the middle of next
week as a series of storm systems track northeast across Northern
Alaska. The first system is currently near Prudhoe Bay and it pushes
a frontal boundary south across the interior this evening before
stalling roughly between Bethel and Central tonight through Sunday
night. The next system is much less amplified and rides along the
frontal boundary Saturday night and Sunday resulting in a relatively
narrow axis of locally heavy rainfall by Monday morning. A pair of
increasingly amplified systems spin up along the West Coast Monday
through Wednesday lifting the frontal northward and focusing heavy
rainfall along the West Coast and Western Interior. Rainfall amounts
of 1 to 3 inches are likely to be widespread within an area bounded
by the YK Delta, the White Mountains, and the West Central Brooks
Range. Heavy amounts in excess of 3 inches are expected mainly at
higher elevations between the YK Delta and the Central Brooks Range.

&&

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

- A frontal boundary moves south across the interior this evening
before stalling roughly between Lake Minchumina and Circle late
tonight.

- Southerly winds through Isabel Pass gust up to 50 mph through
Tuesday with potential for a few stronger gusts Saturday and Monday
evening.

- A disturbance tracks along the front on Sunday bringing moderate
to locally heavy rainfall to all but the southeastern interior
through Monday morning.

- Warmer temperatures and breaks in the cloud cover are possible
Tuesday into Wednesday, particularly near the Canadian border.

West Coast and Western Interior...

- A quasi-stationary frontal boundary wavers across the area through
the middle of next week. Heavy rainfall in excess of 3 inches is
likely between the Nulato Hills and the south-central Brooks Range.

- A low pressure approaches the Seward Peninsula on Monday.
Depending on the low track, it may produce another round of gusty
southwest winds and high surf for the Norton Sound.

North Slope and Brooks Range..

- Rain shifts to the eastern Slope/Brooks Range this evening with
westerly wind gusts up to 40 mph along the coast including Barter
Island.

- Mostly dry weather on Sunday ahead of another round of rain
spreads north of the Brooks Range on Monday.

- Snow may mix with rain at times, particularly in the higher
elevations of the west-central Brooks Range but accumulations are
not expected at this time.

&&

.FORECAST ANALYSIS AND DISCUSSION...

A 995 mb low over the Beaufort Sea drops south across interior
Alaska tonight before stalling. This frontal boundary focuses rain
chances into next week as a series of disturbances track along it.
The first disturbance tracks inland Saturday night and Sunday and is
relatively low amplitude suggesting little frontal movement. As a
result, an axis of frontogenesis should focus a narrow band of
locally heavy rain roughly between Lake Minchumina and Circle
(including the Fairbanks area). A more amplified system spins north
across the Bering Sea toward the Seward Peninsula early Monday
morning at about 990 mb. This system lifts the stalled frontal
boundary northward along the West Coast then across the interior. An
expansive precipitation shield accompanies this feature with EFI
shift of tails values of 1-2+ across most of northwestern Alaska on
both Monday and Tuesday including the North Slope. The southeast
interior is unlikely to see much rain from this otherwise wet
pattern, but the remainder of the eastern interior should receive 1-
2 inches of rain by Monday evening whereas the west coast and
western interior pick up an additional 2-3+ inches. Higher elevation
areas including the Nulato Hills and Brooks Range may receive
localized rainfall amounts over 5 inches. Precipitation rates
diminish Wednesday and Thursday as the impressive atmospheric river
shifts east and moisture gets scoured out by the Alaska Range.
Another amplified system develops near the AK Pen/Bristol Bay on
Wednesday allowing for increasing Chinook flow across the east-
central interior with cool and damp conditions continuing for the
west coast.

&&

.FIRE WEATHER...

Fire weather concerns will be very low across the state with the
exception for the Upper Tanana Valley. Min RH values through the
early next week will dip into the 30s. For Isabel Pass where
southerly winds gusting up to about 45 mph are expected Saturday
afternoon and Monday afternoon with lighter south winds on Sunday.
Elsewhere, light south/southwest winds of 5 to 10 mph are expected
for the end of this week until a more amplified Chinook pattern sets
in by Tuesday or Wednesday. Warming temperatures and less cloud
cover should allow for lower RH across a broader portion of the
eastern interior on Tuesday and Wednesday.

&&

.HYDROLOGY...

A hydrologic outlook in effect for the majority of western and
Northwestern Alaska was expanded to the hills north of Fairbanks.
There will be two additional rounds of heavy precipitation with
areas of light to moderate rain continuing through at least Friday
next week. The next round of heavy rain will focus more on the
Central Interior along a stalled frontal boundary Sunday through
Monday morning. A SW to NE oriented rainfall axis of 1 to 2.0 inches
of rain accompanies this with locally higher amounts up to 3 inches
is expected across the higher elevations of the White Mountains. The
third round spins up the West Coast on Monday and spreads across the
North Slope on Tuesday. Similar rainfall amounts are expected with
the third round resulting in additional rainfall amounts of 1.5 to 3
inches by Tuesday evening from the west coast to the central
Interior. Locally higher amounts in excess of 5 inches are possible
where rainfall is most persistent, particularly at higher elevations
of the West Coast and Western Interior. Furthermore, snow levels
will be relatively high for this event; above 8000 feet allowing for
high elevation glacier melt. Additional rainfall is possible through
the end of the week (heaviest south of the Alaska Range) and rising
water levels are expected for most interior rivers.


&&

.EXTENDED FORECAST DAYS 4-7...

The upper level pattern amplifies considerably Tuesday and Wednesday
before energy cross the AK Peninsula on Thursday. This amplified
pattern results in Chinook flow across the eastern interior
including the potential for a continuation of southerly mountain gap
winds. An isolated thunderstorm or two are possible along the AlCan
border on Wednesday too. Farther west, the wet and dreary pattern
along the west coast and western interior continues through most of
next week, but precipitation rates diminish quickly after Tuesday.
The primary except is the southern slopes of the Alaska Range where
high snow levels should also result in glacier melt contributing to
increasing river levels.

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

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...Wind Advisory for AKZ811-812-832-834-838-842-844.
PK...Small Craft Advisory for PKZ801-802-850.
     Small Craft Advisory for PKZ803-806.
     Small Craft Advisory for PKZ815.
     Small Craft Advisory for PKZ816.
     Small Craft Advisory for PKZ817-851-854.
&&

$$

EK