Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 605 PM EST Sun Dec 25 2022 Valid 12Z Thu Dec 29 2022 - 12Z Mon Jan 02 2023 ...Weather/Hazards Highlights and Guidance/Predictability Assessment and Preferences... Latest models and ensembles are gradually trending toward a more similar mid-larger scale pattern evolution through medium range time scales, bolstering overall forecast confidence. However, guidance still continues to offer ample differences with embedded smaller scale weather systems/features. Differences/uncertainties into later this week mainly relate to modestly weather focusing upper impulse/low translations and from northwest Alaska into the Northern Bering Sea. Differences especially relate with the complex interactions of upper trough/low energies and enhanced local weather focuses rotating out from the southern Bering/Aleutians toward the western Gulf of Alaska/southern tier coastal communities/vicinity and lead low/system energies lifting northward into the Gulf from the North Pacific in active flow. A favored composite of the 12 UTC GFS/ECMWF/Canadian and GEFS/ECMWF ensemble means seems to provide a good forecast basis across the entire forecast domain and tends to smooth-out/mitigate smaller scale system variance consistent with a pattern with near average predictability. This pattern also favors a general temperature moderation trend this week for much of Alaska. Later, there is actually an increasingly favorable signal at longer time frames to ring in 2023 in support of the development and track of a deep low/storm to the south of the Aleutians and into the Gulf of Alaska. The aforementioned favored guidance composite has seemed to begin to lock into a main feature that currently has good observational data coverage over Asia and is slated to generally track bodily eastward over the northern Pacific toward Alaska. This potentially potent storm with low pressure below 960mb given upper support could offer a significant maritime to coastal wind/waves threat. Lead wrapping moisture inland into the Alaskan Peninsula/Kodiak Island and Southcentral Alaska, and to a lesser extent the Panhandle, could fuel a multi-day heavy precipitation and wind threat. WPC product continuity is decently maintained in this forecast plan collaborated between WPC and Alaskan weather offices. Schichtel 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