Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
648 PM EST Wed Jan 17 2024
Valid 12Z Sun Jan 21 2024 - 12Z Thu Jan 25 2024
...Guidance Evaluation/Preferences...
The 12Z/18Z model guidance suite maintains excellent agreement
with the anomalous upper level closed high over the northern
Bering for the weekend into Monday, and reasonably good agreement
with the mainland Alaska trough axis. The guidance has come into
better agreement on the placement of multiple low pressure systems
over the North Pacific, with the CMC now fitting the consensus
better compared to yesterday, although it is slightly to the east
of the GFS/ECMWF with the surface low just south of the Kenai
Peninsula by Tuesday morning. For the arctic trough building in
towards the middle of the week, the CMC is stronger with this
feature overall, and the GFS is slower with the arrival of the
trough compared to a slightly faster ECMWF. The UKMET strayed the
most from consensus across the North Pacific, so the
fronts/pressures forecast was primarily based primarily on a
GFS/ECMWF/CMC compromise through Monday, and then roughly equal
proportions of the GFS/ECMWF/CMC/GEFS/ECENS for mid next week.
...Weather/Hazards Highlights...
A return to frigid temperatures is likely by the weekend, with the
brunt of the coldest air likely over the eastern Interior and in
particular, the Yukon Flats. Overnight lows in the -20s and -30s
are expected, and perhaps even colder in the normally colder
sheltered valleys. Although most of the state should remain dry,
moderate to locally heavy snow is likely from the Kenai Peninsula
to the St. Elias Mountains for the 22nd to the 24th as Pacific
moisture is advected inland. With a strong pressure gradient in
place from the strong high over the mainland to the low pressure
over the Gulf, some strong gap winds can be expected along
portions of the south-central coast and the Panhandle for this
weekend. Strong northerly winds gusting to 50 mph are also
expected for the western Alaska Peninsula and adjacent portions of
the eastern Aleutians.
Hamrick
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