Alaska Extended Forecast Discussion
National Weather Service College Park MD
620 PM EDT Sat Oct 25 2025

Valid 12Z Wed 29 Oct 2025 - 12Z Sun 02 Nov 2025

...HEAVY MOUNTAIN SNOW AND LOWER-ELEVATION RAIN EXPECTED ACROSS
THE PANHANDLE LATE THIS WEEK...

...Synoptic Overview...

Through the end of the workweek and into the weekend, the synoptic
pattern will feature a large upper level trough with embedded 
lows starting out Wednesday over the Bering Strait down to the
Aleutians. The multiple lows over the Aleutians will combine into
one low over the western Gulf by Friday. Meanwhile the entire
longwave trough will shift east to over western Alaska. Once
there, the entire pattern is likely to get stuck with the center
of the upper low remaining over the western Gulf through the
weekend. The upper low will get down to about 510 m, meaning the
air mass over much of the state will be cold...with highs in the
low to mid 30s and lows in the teens. However, limited moisture
will be confined to near the lows over the Aleutians and the Gulf,
meaning most of the precipitation will focus into the Panhandle
and the Wrangells.

...Guidance Evaluation and Preferences...

The guidance was in very poor agreement considering the relatively
unchanging nature of the upper level pattern. Ultimately, the
guidance could not decide on how fast, strong, or where the most
potent upper level shortwaves would track, which then led to
large differences in where the resulting surface lows track. Given
this, the 00Z EC and the 12Z GFS appeared to be in the best
agreement of the deterministics with each other, though that
agreement was not very much. A blend of the two was used for the
D4/Wed and D5/Thu periods. After that, the ensembles (GFS & EC)
were used almost entirely for the D6 through D8 periods. As is
typical with the ensembles, the smaller but nonetheless important
features such as shortwaves and smaller surface lows are lost in
the ensemble blend, so the days 7 and 8 upper level forecasts are
nearly identical to one another, due to the extremely low
predictability of the locations and speeds of any lows that would
perturb the upper level pattern. Thus, it's likely when those
features are better resolved that there will be many more
differences in the overall upper level pattern, including those
that may help to move the upper level trough along.

...Weather/Hazards Highlights...

Despite the aforementioned low predictability, the upper level low
at the base of the longwave trough will likely cause enough
forcing to be present to allow for a strong 970s low to move into
the Gulf Friday. The leading front will bring a period of heavy
precipitation, most likely on D5/Thursday into the Panhandle.
Temperatures will be cold enough aloft to support higher elevation
snows, while most of the population at lower elevations will see
periods of heavy rain, especially as that leading front moves
ashore. A prolonged period of onshore flow (subject to change
based on the unresolved tracks of any smaller surface lows), will
keep unsettled conditions ongoing across the Panhandle into the
weekend, though at diminishing intensity with time. Thus, the
heavy precipitation area in the hazards remains unchanged with
this forecast update. Despite the low central pressure of the
surface low, its track likely staying offshore of the Panhandle
should keep any high winds confined to the typical barrier jets,
and likely will not move into the inner channels of the Panhandle.
Thus, the high winds hazard was removed with this update in
coordination with the AJK/Juneau, AK forecast office.

&&

Wegman



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