Alaska Extended Forecast Discussion
National Weather Service College Park MD
758 PM EDT Thu Oct 9 2025
Valid 12Z Mon 13 Oct 2025 - 12Z Fri 17 Oct 2025
...Series of potent storms offer Aleutians to western and
southern Alaska high wind/wave and heavy rain threats...
...Guidance Evaluation and Preferences...
A mean trough will be present through the extended period over the
Bering Sea. Multiple deep, closed lows will lift northward while
while several impulses of energy ejects from the flow into the
Gulf of Alaska/Mainland. Guidance is above average on clustering
on Day 4 however quickly returns to near average with the
evolution of low at the beginning of the week. Spread increases
by midweek and beyond, particularly across the Gulf of Alaska.
Impulses and increase moisture within the flow will maintain the
potential for wet and unsettled conditions on the southern part of
the state.
Maintained continuity by starting with a compromise of the
CMC/EC/GFS; including the EC/GEFS means for Day 5 and then
bumping up to a 50/50 deterministic to means ratio from forecast hour
180 and beyond.
...Weather/Hazards Highlights...
An active pattern will support multiple days with locally
enhanced winds and precipitation. A closed upper low/trough
will support a main deep mean surface storm/low position over the
Aleutians and Bering Sea late week through early next week that
will offer a prolonged opportunity for periods of high winds/waves
and wrapping rainfall. Approach and downstream undercutting
energy and system/frontal progression across the Alaska Peninsula
into the Gulf of Alaska should act to enhance lead inflow to fuel
growing precipitation to spread across Kodiak Island and
SouthCentral to Southeast Alaska Sunday into early next week with
downstream translation. Additional deep low approach on the heels
of this system will renew potential for scattered to widespread
precipitation and strong winds for the southern tier of the state.
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