Severe Thunderstorm Warning 1, NWS Fairbanks, AK

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
313 PM AKDT Mon Jun 16 2025

.SYNOPSIS...
Warmer than normal conditions continue across much of the region
along with hazy skies courtesy of Canadian wildfires burning to
our east. Coverage of afternoon and evening thunderstorms will
continue to increase the next couple of days, with most of the
activity along the Alaska Range and over the western interior.
Later this week coverage of storms will shrink a bit as activity
shifts back over the central and eastern interior.

&&

.KEY WEATHER MESSAGES...
Central and Eastern Interior...
- Warm weather continues with highs in the mid to upper 80s
  remaining through much of the week.
	- See heat advisory for additional details.

- Isolated thunderstorms expected later Monday afternoon and
  evening with greater potential west of Fairbanks. Thunderstorm
  potential increases for Wednesday and Thursday in the Tanana
  Valley and Fortymile Country.

West Coast and Western Interior...
- Showers and widely scattered thunderstorms continue over Western
  Interior Monday and Tuesday afternoons.
	- The greatest thunderstorm potential is in the Western Interior
   south of Huslia both days.

- Temperatures in the 70s to low 80s for the Western Interior and
  the 60s for the coast expected to persist through most of the
  week.

North Slope and Brooks Range..
- Temperatures in the upper 60s to mid 70s on the Arctic Plain and
  in the 50s and 60s along the coast persist through most of the
  week.

- Rapid snowmelt continues to result in rapid rises on rivers.

- Isolated afternoon thunderstorms along the southern slopes of
  the Western Brooks Range possible through Tuesday.

&&

.FORECAST ANALYSIS AND DISCUSSION...
The current weather setup across the region will continue to
dominate the forecast for several more days. An omega block
continues with an impressive and expansive 570 dam 500 mb ridge
over northern Alaska which is sandwiched between upper lows over
the Bering and eastern Gulf of Alaska. Given these positions, the
ridge continues to suppress storm activity across most of
northern Alaska and eastern portions of the interior with
shortwave energy from the Gulf of Alaska low tracking into the
western interior where scattered to numerous thunderstorms will be
realized Monday evening and Tuesday afternoon and evening. By
midweek the ridge will weaken ever so slightly as it shifts slowly
southward. However enough moisture will remain trapped under the
ridge to generate at least some scattered thunderstorms throughout
the interior and near the Alaska range on a daily basis.

Temperatures currently are running as much as 15 to in some cases,
20 degrees above normal. As such, the heat advisory will continue
for at least one more day. Even if the heat advisory is allowed
to expire, temps will remain well above normal for the rest of the
week and into the weekend as the ridge remains in place.
Meanwhile the haze from Canadian wildfires will remain in place
through Tuesday, but higher resolution models show smoke plume
concentrations lessening a bit as the week wears on with the main
plume shifting a bit further south in response to the shifting of
the upper ridge later in the week.

Hydro concerns will continue through the week as rapid snowmelt
across the Brooks range drains onto the North Slope with
associated river rises and localized ice jam flooding as break-up
continues across the north.

&&

.FIRE WEATHER...
With thunderstorm coverage increasing the next few days, the
threat of lightning caused fires will be on the increase,
especially across portions of the western interior where storm
coverage will be the greatest the next couple of days. As such the
decision was made to upgrade the Fire Weather Watch to Red Flag
Warning for Tuesday across west central fire zones. Min RH values
will only drop to around 30 percent Tuesday in this area, but
very warm temperatures and plentiful surface fuels will keep the
fire threat elevated. Meanwhile warm and very dry conditions will
continue across the rest of the interior. A Red Flag Warning is
also remains in place for the Yukon flats and nearby elevated
terrain due to an expected increase across the region.

&&

.HYDROLOGY...
Rivers continue to breakup across the North Slope. River levels
are continuing to rise and are now to likely crest middle to late
week. On the Sag, there has been an emergency closure of the
Dalton Highway between MP 305 and MP 356 due to a major washout at
MP 315 caused by a failed culvert as well as water over topping
the road at several other spots. On the Colville, flooding is
occurring at Umiat with ice jams present further downstream.
Additional flooding could occur downstream over the next couple
of days as these ice jams release.

&&

.EXTENDED FORECAST DAYS 4-7...
Warm weather will continue across much of Northern Alaska as an
upper-level ridge over the northeastern mainland gradually shifts
to the southeast during the extended time frame. Thunderstorms
will also be possible across wide swaths of the Interior and some
parts of the West Coast during this time frame. Strengthening low
pressure moving into the Bering Sea late this week may lead to
to somewhat cooler temperatures across parts of Western Alaska,
but there is low confidence on the track of this low. Meanwhile, as
the ridge shifts to the southeast, the extent of the warmest
(especially >80F) temperatures may also retreat eastward a bit.

&&

Coastal Hazard Potential Days 3 and 4...None

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...Flood Watch for AKZ804>806-808>810.
     Red Flag Warning for AKZ929-930-952.
     Red Flag Warning for AKZ931>934.
     Heat Advisory for AKZ833>835-838>846.
PK...None.

&&

Laney