Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 413 PM EST Thu Nov 12 2020 Valid 12Z Mon Nov 16 2020 - 12Z Fri Nov 20 2020 ...Guidance/Predictability Assessment... The WPC Alaskan medium range product suite was primarily derived from a blend of the 12 UTC GEFS/ECMWF ensemble means and the 19 UTC National Blend of Models days 4-8. Opted for only a quite limited inclusion of deterministic model guidance due to smaller scale system and phasing variance that is evident earlier than normal by the start of this forecast period. WPC continuity was well maintained with this forecast strategy. ...Weather/Threats Highlights... Above normal temperature should persist over the North Slope for the next week and western Alaska under upper ridging, but expect a cooling trend that will lead to below to much below normal temperatures for much of the rest of the mainland into early next week as an amplified upper trough works from the Interior to the Gulf of Alaska. The upper trough favors unsettled conditions, especially for the Southeast Panhandle. Cooled temperatures and unsettled flow then overall moderates as support weakens/heights rise. Upstream, systems traversing the Bering Sea/Aleutians early next week will gradually weaken into the lead/amplified upper ridge, but still present unsettled maritime conditions and some onshore precipitation into western/northwestern Alaska. There is then an increasing guidance signal supporting additional upper trough/closed low development and approach into the Bering Sea and Aleutians through mid-later next week that would bring a threat for periods of enhanced winds/waves and precipitation across the region, then increasingly with time into portions of western and southwestern/southern Alaska. Schichtel Additional 3-7 Day Hazard information can be found on the WPC medium range hazards chart at: https://www.wpc.ncep.noaa.gov/threats/threats.php Hazards: - Much below normal temperatures across portions of mainland Alaska, Sun-Mon, Nov 15-Nov 16. 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