Alaska Extended Forecast Discussion
National Weather Service College Park MD
653 PM EDT Sat Mar 14 2026

Valid 12Z Wed 18 Mar 2026 - 12Z Sun 22 Mar 2026


...Overview...

Upper troughing will be in place across the Alaska Mainland at
the start of the forecast period midweek. Energy dropping south
from the Beaufort Sea should reinforce this trough late week and
eventually lead to a closed upper low over the Gulf of Alaska by
next weekend. This pattern will bring cold conditions with much
below average temperatures across most of the state. Modest
precipitation is possible in Southeast Alaska as weak but
persistent low pressure sets up in the Gulf, with gusty gap winds
for areas near the Alaska Peninsula and Kodiak Island behind the
low.


...Guidance Evaluation and Preferences...

Model guidance is quite agreeable with the large scale pattern
described above, as energies create troughing over the state to
the east of a western Bering Sea/eastern Siberia upper ridge.
There are typical variations on the smaller scale, with exact
timing of shortwaves and placement of surface lows at any given
time, but there were not any clear outliers with the 12Z model
guidance. One model difference is with the potential for upper
ridging to poke into northwestern Alaska by next weekend to the
north of the Gulf upper low. Most AI/deterministic runs in the 12Z
cycle show some ridging influence coming from the eastern Siberia
upper high/ridge, aside from the CMC that was stronger than
consensus with the upper low and spread the low's influence
farther north than other models.

With the reasonable guidance agreement, the WPC forecast began
the forecast period with a general model blend (ECMWF, GFS, CMC,
UKMET, and AIFS). As the period progressed, used some ensemble
means in the blend to temper individual model differences, with
the ensemble means reaching about half by Days 7-8.


...Weather/Hazards Highlights...

Stacked Gulf troughing/low pressure will lead to mean northerly
cold and dry flow across much of the Mainland next week. But some
moist southwesterly inflow will affect the southern coast of
Alaska, especially Southeast Alaska (Panhandle), on the northern
side of a persistent atmospheric river directed at British
Columbia. Precipitation amounts should stay modest from day to day
rather than heavy, but a wet pattern is likely. Some
precipitation could stretch back to parts of Southcentral at
times. Light precipitation in northerly/northwesterly flow is
possible for the eastern Aleutians to Alaska Peninsula at times,
but more impactful in that area will likely be moderate to strong
gap winds. Though winds there may stay under 50kt, the moderately
high winds could cause hazards to fishing/shipping traffic.
Meanwhile winds may channel near the Bering Strait and between St.
Lawrence Island and the Seward Peninsula. Another potential
hazard could be possibly multiple rounds of ground blizzard
conditions across eastern coastal areas of the North Slope through
the period.

Colder than average conditions are forecast for most of the state
through late week under the upper trough. Temperature anomalies
will be 20 to 40+ degrees below average in many areas of the
Interior to Alaska Range, yielding forecast lows into the -20s and
-30s and highs on either side of 0F. Southcentral can expect
highs generally in the teens, while Southeast should see colder
than normal temperatures (but less dramatic than other areas)
generally in the 30s. The cold may moderate somewhat by next
weekend, but still stay chilly. The North Slope is forecast to
remain nearest to average, with northwestern areas even possibly
reaching above normal by next weekend especially if the upper
ridge pokes into the region.


Tate


Additional 3-7 Day Hazard Information can be found on the WPC
medium range hazards outlook chart at:
https://www.wpc.ncep.noaa.gov/threats/threats.php

WPC medium range Alaskan products including 500mb, surface
fronts/pressures progs and sensible weather grids can also be
found at:

https://www.wpc.ncep.noaa.gov/alaska/ak_5dayfcst500_wbg.gif
https://www.wpc.ncep.noaa.gov/alaska/akmedr.shtml
https://www.wpc.ncep.noaa.gov/alaska/ak_5km_gridsbody.html