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FXAK02 KWNH 212049
PMDAK

Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
349 PM EST Thu Nov 21 2024

Valid 12Z Mon Nov 25 2024 - 12Z Fri Nov 29 2024

...A shot of snow expected for western and central Alaska this
weekend...
...Enhanced gap winds for a cooled Southeast Alaska mid to late
next-week...


...Guidance Evaluation/Preferences...
The guidance remains in good agreement with a potentially
impactful low moving through AK Sunday.  The big outlier overall
was the 12z Canadian, which showed a much more zonal flow
region-wide.  When the guidance was most agreeable, used a
composite 12z GFS/ECMWF/UKMET/Canadian model blend early on before
including more strongly than usual towards the 12z NAEFS/ECMWF
ensemble means with time.  Most of the grids are 19z NBM weighted,
as usual.  The QPF was more heavily weighted toward the GFS/ECMWF
than the Canadian.


...Weather/Hazards Highlights...
A shot of moderate to heavy snow is expected in western and
central Alaska this weekend as a cyclone moves by.  This system
should bring gale-force winds near the Bering Strait.  The
multi-day trend in the guidance is for ridging across AK to break
down and retrograde west into the Bering Sea and eastern Siberia,
leading to a cooling trend for southern AK.  As is typical, the
coldest readings will be on the North Slope and eastern interior.
In the wake of the front, gap winds should strengthen/renew near
the AK Panhandle early to mid next week.  The guidance continues
to waffle on cyclone(s) approaching the Aleutians, though there is
greater consensus on one approaching late Monday.  Gale force
winds are still anticipated in the Aleutians, with storm force
winds possible across portions of the southern Bering Sea late
Monday through Tuesday.

Roth


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

$$