Alaska Extended Forecast Discussion
National Weather Service College Park MD
640 PM EST Tue Dec 9 2025

Valid 12Z Sat 13 Dec 2025 - 12Z Wed 17 Dec 2025


...Overview...

The large scale pattern over Alaska during the upcoming medium 
range period will be rather stagnant as an omega block sets up 
over the region. This is anchored by a mid-upper level high over 
the Bering Sea, with height anomalies over 3 standard deviations 
above normal. This will maintain troughing over eastern Alaska 
into the Gulf, as a couple of low pressure systems rotate into the
Gulf. Moisture will funnel into Southeast Alaska for the weekend 
into Monday associated with a cold front. Additionally, northerly 
flow on the backside of the Gulf low(s) could lead to strong gap 
winds for the weekend into early next week.


...Guidance Evaluation and Preferences...

The guidance continues to show reasonably good agreement on the 
overall pattern through much of the period. The upper high will 
meander over the Bering Sea the entire period. To the east, a 
vortex will drop south across eastern Alaska to form a deep 
trough/closed low over the Gulf. Energy south of the Aleutians 
will rotate into the Gulf low to help reinforce it into next week.
The main uncertainties during the period are in the details of 
these individual shortwaves/lows into the Gulf and with the 
overall ridge/trough interface location. A blend of the 
deterministic guidance served as a good starting point for the WPC
forecast today, with increasing weighting of the ensemble means 
for the latter half of the period.


...Weather/Hazards Highlights...

Mean low pressure for the Gulf over the weekend and into early 
next week should lead to moist southwesterly flow into Southeast 
Alaska for some precipitation. Cold temperatures in place will 
mean most of this precipitation falls as snow, and moderate snow 
totals are likely on Sunday and Monday especially. Behind the mean
surface low, strong gap winds are possible given the tight 
pressure gradient. While the details are still uncertain, the 
pattern for northerly gap winds will be favorable across the 
Alaska Peninsula toward Cook Inlet and Prince William Sound. 
Outflow winds are also possible for portions of Southeast Alaska 
in the Yakutat and northern Panhandle vicinity. High wind areas 
are in place on the Day 3-7 Hazards product.

Temperatures for much of Alaska will trend much colder through 
the period, with anomalies 20-40 degrees below normal expected by 
the middle of next week. This could mean daily min temperatures as
low as -40 for parts of the eastern Interior, and near or below 
zero for southern locations such as Anchorage. Southern parts of 
the Panhandle may not be as anomalous as the rest of the state due
to relatively warmer moist inflow. And across the North Slope, 
temperatures should be near or above normal.


Santorelli


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