Alaska Extended Forecast Discussion
National Weather Service College Park MD
636 PM EST Thu Dec 4 2025

Valid 12Z Mon 08 Dec 2025 - 12Z Fri 12 Dec 2025


...Overview...

Siberian High pressure will continue to expand into the western
part of the state through the coming week. Meanwhile, the low near
the Gulf Coast will continue to amplify keeping heavy rain and
mountain snow possible for portions of the southern tier and
Southeast. This low will also generate gap winds, particularly for
Kodiak Island, Kenai Peninsula, Cook Inlet and points east across
south-central Alaska. 


...Guidance Evaluation and Preferences...

The last few runs of the ECMWF have noted a more progressive
evolution in moving the mean low and individual fronts to the
eastern Gulf faster. The UKMET was even further east from the rest
of the cluster and therefore was avoided for this forecast cycle.
The CMC has trended closer to the GFS during recent runs,
although notably 5-10 mb deeper than other solutions. Both the CMC
and GFS favor a more westward tail/elongated trough over the Gulf
and into the North Pacific along with a long along the Gulf Coast
that is not so quick to reach the Panhandle. The WPC blend 
utilized the ECMWF/GFS/CMC/EC and GEFS mean for the extended
period, with higher weighting toward the GFS and EC mean with 
time.


...Weather/Hazards Highlights...

Multiple shortwaves crossing into the Gulf will merge into the low
in the Gulf, maintaining a mean trough and wet unsettled pattern
for the southern/southeast tier of the state. Heavy Rain and 
mountain snow along with strong, gusty winds will accompany this 
low near the Gulf Coast. High pressure from eastern Siberia to 
the North Slope will promote below average temperatures for those 
areas with the strong, gusty northeast winds. Temperatures over 
portions of the Interior/Yukon Flats will continue to moderate 
through the week.

Campbell


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