Alaska Extended Forecast Discussion
National Weather Service College Park MD
654 PM EST Wed Nov 19 2025

Valid 12Z Sun 23 Nov 2025 - 12Z Thu 27 Nov 2025

...Overview...

A blocky pattern will be in place across Alaska for the weekend
into much of next week. At the start of the period Sunday, a weak
low across the Gulf, a stronger and longer lasting upper/surface
low over the Aleutians, and an upper high near the Bering Strait
anchoring a ridge over parts of the Mainland will create an omega
block aloft. The Aleutians low could lead to some high winds over
the weekend. As the high moves northeast into the Arctic Ocean,
energy over the Aleutians should undercut it and slowly move east,
spreading modest precipitation over the Alaska Peninsula and
across the southern coast. Colder temperatures are forecast next
week after an above average period in the short range. 


...Guidance Evaluation and Preferences...

Model guidance is reasonably agreeable with the initial omega 
block pattern described above. There are some minor model 
differences with the placement of the surface low near or over the
Aleutians, with most 12Z guidance south of the islands whereas 
the 06Z GFS and the ensembles still have hints that the low could 
be over or north, affecting potential strong wind directions and 
timing. There is a general trend for the low to weaken as it moves
east with some uncertainty in a dual low structure into Monday-
Tuesday. Farther east, after the Gulf low weakens and pulls 
eastward, there is good agreement for surface ridging to build in 
western Canada and into the eastern Mainland. Aloft, there are 
some model differences with the upper high as it tracks northeast.
Most models have trended slower with its movement compared to a 
day ago, with a more southwestern position early next week 
compared to the previous WPC forecast. Then variations arise with 
how far north or south the high is by the middle of next week. GFS
and GFS Graphcast are generally on the southern side atop the 
North Slope, as energy from the Arctic Circle pushes the high 
southward, which other models do not show. The ECMWF is farther 
north into the Arctic with the upper high, with the EC-AIFS and 
the CMC in between. A middle ground position seems reasonable and 
model differences are not too large for the Day 7-8 period.

The WPC forecast was based on a multi-model blend of the 
deterministic guidance early in the period, and blended in 
ensemble means in increasing proportions to half by the end of the
period.


...Weather/Hazards Highlights...

The reasonably strong low pressure system (960s mb) near the 
Aleutians over the weekend could lead to high winds across western
and central portions of the Aleutians, first as southerlies and 
then wraparound winds on the backside of the low, along with some 
precipitation. Meanwhile the weaker low in the Gulf could promote 
some light to moderate precipitation from Prince William Sound 
into Southeast Alaska, while some light snow is possible across 
the Interior.

Into the workweek, precipitation will spread across the Alaska 
Peninsula with the primary low, while light precipitation is 
possible across the southern coast. As the low gets stalled by the
upper ridge, QPF amounts of a few inches could eventually pile up
next week over favored areas of the Alaska Peninsula into favored
areas of Kodiak Island and the Kenai Peninsula, but likely to 
stay below hazardous levels since the precipitation falls over 
several days. Meanwhile, Interior Alaska should generally see 
clearer skies and little to no precipitation into next week as 
high pressure at the surface develops. This surface high will 
contrast with lower pressures over the Gulf, creating a pressure 
gradient pattern for possible gap winds across parts of 
Southcentral and Southeast that will continue to be monitored.

The surface ridge over at least eastern portions of the Interior 
will lead to cold continental flow, cooling temperatures compared 
to the relatively warm short range period. Highs in the single 
digits will be common with lows in the negatives. Slightly below 
average highs are possible in Southeast as well. Meanwhile above 
average temperatures could spread across the Alaska Peninsula into
the Lower Kuskokwim and Kodiak Island given relatively warmer 
oceanic flow.


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