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FXAK69 PAFG 020517 CCA
AFDAFG

Northern Alaska Forecast Discussion...CORRECTED
National Weather Service Fairbanks AK
917 PM AKDT Fri Aug 1 2025

.SYNOPSIS...There is potential for very heavy rain over the Upper
Tanana Valley and Eastern Alaska Range this evening and into
Saturday morning. See Special Weather Statement for details.
Otherwise, a warm and dry weekend is in store for most areas with
just a few isolated thunderstorms scattered across the Interior.
Increasing rain and cooling temperatures expected Monday along the
North Slope along with increased thunderstorm activity in the
Interior on Monday as an Arctic trough begins to drop south.

&&

.KEY WEATHER MESSAGES...
Central and Eastern Interior...
- Dry and warm weather with plenty of sunshine through Monday for
  most areas.

- Heavy rain potential over the Upper Tanana Valley and eastern
  Alaska Range Friday evening into Saturday morning. See Special
  Weather Statement and Hydrology section for more details.

- Widely scattered thunderstorms from Minchumina to Tanana to the
  White Mountains on Monday, with isolated storms east of Chena
  Hot Springs on Saturday, and near Tanana and along the Taylor
  Highway on Sunday.

West Coast and Western Interior...
- Dry and warmer weather through the weekend with highs 5 to 10
  degrees above normal.

- Isolated thunderstorm chances in the Western AK Range and near
  McGrath Friday afternoon, Lower Yukon/Kusko Valley on Saturday,
  Middle Yukon Valley on Sunday, and from McGrath to Huslia on
  Monday.

- Increasing southeast winds with peak gusts to 35 mph and
  isolated showers in the YK Delta Friday evening into Saturday

North Slope and Brooks Range...
- Clear skies along the coast as offshore flow dominates. There
  may be some stratus or fog returning each night, but the
  afternoons should be nicer and warmer overall.

- Isolated showers in the Brooks Range, but overall it will be a
  warmer and drier weekend.

- Increasing rain and cooling temperatures for all areas on
  Monday as an Arctic trough drops south over the area.

&&

.FORECAST ANALYSIS AND DISCUSSION...A ridge of high pressure
persists over the area while low pressure systems lie over the
Gulf of Alaska and Western Bering Sea. A shortwave rotating
around the north side of the low in the Gulf of Alaska is bringing
a narrow band of organized convection over the Yukon Territory
this afternoon (Friday). This band will move into the eastern
Interior as heavy showers overnight Friday into Saturday. Rainfall
rates as high as 1" per hour are possible across the eastern
Alaska Range and Upper Tanana Valley east of Dot Lake. See Special
Weather Statement for more details. This system will fall apart
quickly Saturday and Saturday night and the ridge of high pressure
will persist. By Saturday, precipitation from the low in the
Bering Sea will spread to the southern Yukon Delta. Monday will
see an increase in showers and thunderstorms across the central
Interior as the lows begin to converge and colder air from the
Arctic trough to the north begins to drop south. The Arctic trough
will bring significant rainfall to the North Slope and northern
Brooks Range Sunday night through Tuesday morning.

Models are in good agreement on the short term forecast pattern.
We used a blend of models for the forecast today. We based QPF
amounts over the eastern Interior on HREF data and added widely
scattered thunderstorms from Minchumina to Tanana to the White
Mountains on Monday afternoon.

&&

.FIRE WEATHER...Ridging and warm temperatures persist over most of
northern Alaska through the weekend. The driest RHs will be in the
25-30% range over the Yukon Flats on Saturday. Southerly gap winds
will gust to 40 mph through Alaska Range passes on Saturday as
well. While the North Slope has been warm and dry, significant
rainfall of 0.5-1.5" is expected Monday through Friday of this
week. We have added widely scattered thunderstorms to the forecast
for Monday from Minchumina to Tanana to the White Mountains.
Instability will be present Monday as lows in the Bering Sea and
Gulf of Alaska converge as the Arctic trough drops south, bringing
colder air aloft. However, westerly flow aloft should prohibit
more than widely scattered activity mainly over terrain.
Temperatures nonetheless remain above normal for most areas
through Thursday before significant cooling is expected over the
weekend.

&&

.HYDROLOGY...A system bringing abundant rainfall will move quickly from east to
west across the Upper Tanana Valley and Alaska Range Friday
evening into Saturday. Rainfall rates of 1" per hour are possible
from 7pm Friday evening through around 10am Saturday morning.
Rainfall will begin along the Alaska Highway near the Alcan
Border and move west to Dry Creek and over the eastern Alaska
Range overnight. Short run creeks along the Alaska Highway from
Dot lake to Tok may run high and fast, as well as streams
draining the Macomb Plateau. Outdoor recreationists should be
aware of the threat for heavy rain, high water, and debris flowing
down typically dry streambeds.

&&

.EXTENDED FORECAST DAYS 4-7...Models are in agreement on a
gradually wetter and cooler pattern inbound for northern Alaska.
The main feature of interest is an Arctic low that looks to drop
south next weekend. Some models indicate there is potential for
this to drop south over the North Slope before swinging through
the state bringing unseasonably cool temperatures and the
potential for snow from the Brooks Range north. Other models bring
the core of the low and cold air south over the Bering Strait.
This would still be a cool pattern, but southerly flow east of the
low would moderate things considerably. We will continue to
monitor and blend the extended forecast toward a middle ground
solution.

Coastal Hazard Potential Days 3 and 4...None

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...None.
PK...Small Craft Advisory for PKZ801.
     Small Craft Advisory for PKZ816-850.
     Small Craft Advisory for PKZ851.
&&

$$

Chriest