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FXAK69 PAFG 232352
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
352 PM AKDT Fri May 23 2025

.SYNOPSIS...An easterly wave pattern setting up will bring
increasing chances for thunderstorms across the Interior along
with areas of heavy rain this weekend. An arctic trough swinging
south from the Chukchi Sea will enhance this activity and also
bring light snow to the North Slope and Brooks Range. The West
Coast will be spared from most of the action with mostly dry
conditions and a warming trend through the weekend.

&&

.KEY WEATHER MESSAGES...
Central and Eastern Interior...
-Warming trend through the weekend. Highs increase to near 70
 this weekend for Interior valleys.

-Isolated thunderstorms this afternoon south of the Yukon River.
 Thunderstorms increase in coverage on Saturday with widely
 scattered storms from Northway to Chicken and isolated storms
 south of the Yukon River. Sunday will bring widely scattered
 thunderstorms east of Fairbanks.

-Showers and thunderstorms Friday through Monday may produce very
 heavy rain. See Special Weather Statement for details. The area
 of biggest concern is from Delta Junction to Tok along the Alaska
 Highway.

West Coast and Western Interior...
-Warming trend through the weekend. Highs near 60 in the Western
 Interior today increase to the low to mid 60s this weekend.

-Mostly dry conditions expected through the weekend except near
 thunderstorms in the southwest Interior northeast of Holy Cross.

North Slope and Brooks Range..

-Winds become westerly behind the arctic front passage on Sunday.

-Areas of low stratus persist through the weekend.

-Light snow accumulations Saturday through Monday, mainly 1-2"
 from Umiat east, though up to 4 inches is possible through Atigun
 Pass and at Kaktovik.

&&

.FORECAST ANALYSIS AND DISCUSSION...A significant pattern shift is
underway with a low in the Gulf of Alaska beginning to move
shortwaves from the east into the Interior as an Arctic trough
swings south from the Chukchi Sea. These features will interact
and set up a favorable pattern for slow moving thunderstorms and
very heavy rain over the Central and Eastern Interior this
weekend. Not all areas will see rainfall and/or thunderstorms, but
rainfall with these storms will be heavy enough to cause concern
for rapidly rising creeks and streams, especially near steep
terrain.

Models are in okay agreement on the overall pattern shift, but
have very high uncertainty on the details. Models have overall
slowed down the progression of the arctic trough from east to
west, which will prolong the length of unstable conditions over
the area. Thunderstorms may persist all night Sunday night into
Monday morning across the eastern Interior with the heaviest
precipitation likely Monday morning east of Delta Junction.


&&

.FIRE WEATHER...A number of easterly wave events will bring
increased thunderstorm activity to the Interior this weekend.
Expect widely scattered thunderstorms from Northway to Chicken
on Saturday and from Fairbanks to Circle to Eagle to the Alcan
Border on Sunday. Isolated thunderstorms are expected both days
across most of the rest of the Interior. These storms will be
exceptionally wet and have the potential to drop very heavy rain
as they will be nearly stationary with very little storm motion.
Thunderstorms may persist all night Sunday night into Monday
morning east of Dot Lake. Temperatures will rise to near 70 in
warm valleys on Sunday, then gradually cool heading into next week
as an Arctic trough passes from west to east, which will
stabilize conditions. Minimum RH will remain 30% or better through
the short term and the extended. Next week will bring more chances
for scattered thunderstorms, though these look very wet as well.

&&

.HYDROLOGY...Degraded ice remains in place at the mouth of the
Yukon River. Snowmelt has begun in the Porcupine watershed in
Canada and water is starting to pool on the ice of the Porcupine
River. Between the border and the Yukon River ice is degrading
with some areas opening up. Breakup has begun on the Kobuk River.
The river broke up at Shungnak on or around May 16th with no
issues. Ice remains in place at Ambler and water levels are slowly
starting to rise as the ice decays in place.

Creeks and streams in the eastern Interior may rise rapidly under
areas of heavy rain Friday through Monday. Rising freezing levels
on Sunday will allow snowmelt from high terrain above Cathedral
Rapids and Sheep Creek along the Alaska Highway to add to rainfall
in those streams. This may cause very high water in these streams
along the Alaska Highway.

&&

.EXTENDED FORECAST DAYS 4-7...Active weather will continue across
the central and eastern Interior through next week with multiple
rounds of heavy showers and thunderstorms expected. The best
chance for a significant event looks to be Wednesday and Thursday.
The North Slope will continue to see intermittent light snow
showers as low pressure remains in the area. The West Coast will
see mainly dry and quiet conditions.

Coastal Hazard Potential Days 3 and 4...None

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...None.
PK...None.
&&

$$

Chriest