Alaska Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
347 PM EST Wed Jan 04 2023
Valid 12Z Sun Jan 08 2023 - 12Z Thu Jan 12 2023
...Overview and Guidance/Predictability Assessment...
The guidance is agreeable on showing weakening cyclones over
portions of the Bering Sea and northeast Pacific well north of the
main band of the Westerlies, which are depressed into the 30s
latitude, with occluded cyclones tracking closer to the mid to
upper 40s latitude, south of the state. Other than the 12z GFS
being a little stronger with mid-level troughing across western
AK, the guidance is fairly agreeable. To deal with the detail
issues including the GFS apparent issues in those locations, used
a blend of the 12z GFS, 12z ECMWF, 12z Canadian, and 12z UKMET
this weekend for the 500 hPa heights, pressures, fronts, and
winds, before blending in up to half of the 12z NAEFS/00z ECMWF
early next week. The remainder of the grids were closer to the
19z NBM, as it standard.
...Weather/Hazards Highlights...
A low pressure center is forecast to move north to northwest into
the Gulf of Alaska this weekend before fading while moving inland.
Another low in the southern Bering Sea should be doing the same
this weekend. Some moisture from the Pacific will likely flow
northward with the lows and overspread portions of the the AK
Panhandle, South Central AK, and the Aleutians which have the
higher rain chances this period and the potential for 2-4" of
rain. Gales are likely to spread across portions of the Upper
Aleutians, Bering Sea, and northeast Pacific/Gulf of AK, with some
potential for storm force winds in the Bering Sea early to mid
next week as strong lows moving south of AK tighten up the
pressure gradient in those areas. Mildness should remain across
the Aleutians and southern AK coast with seasonably cold and dry
conditions across the Interior.
Roth
No significant hazards are expected over Alaska during this
forecast period.
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