Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 726 PM EDT Thu Oct 28 2021 Valid 12Z Mon Nov 01 2021 - 12Z Fri Nov 05 2021 ...Overview and Model Guidance... A complex weather pattern will remain quite stormy around much of Alaska through medium range time scales. The flow will feature several potent Bering Sea, Arctic, and Gulf of Alaskan surface lows rotating within energetic/closed mean upper troughs over these areas and around the periphery of an amplified western Canada to Interior mean upper ridge. The storms will include a moist and deepened extratropical low associated with current west Pacific Typhoon Malou. 12 UTC GFS/ECMWF solutions seem well enough clustered days 4-6 (Monday-Wednesday) with the main storms and a compromise between the two for system amplitude differences across the higher latitudes and elsewhere also seems reasonable considering near average but slowly decreasing predictability.ÂForecast spread and uncertainty increases more rapidly into day 7/8 (Thu-next Friday) when a solution more weighted to the still compatible but less detailed 12 UTC GEFS/ECMWF ensemble means seem a better way to go given well organized systems remain depicted and manual adjustments can be applied to ensure sufficiently deep lows consistent with favorable upper support. ...Weather/Hazard Highlights... A storm over the east-central Gulf of Alaska Monday is expected to wrap into the northwest Gulf Tuesday and weaken while lifting northward over western Alaska and into the Arctic Ocean around the Interior upper ridge. A threat for high waves/winds and heavy precipitation will spread across southern Alaska before lifting into higher latitudes with a more modest weather focus. On the heels of this system, guidance indicates that a moist and deepened extratropical low associated with current western Pacific Typhoon Malou will lift into the eastern Gulf of Alaska Tuesday and rotate to the northern Gulf by Wednesday. This offers another threat for high winds/waves and heavy precipitation spread inland from southeast to southern Alaska and onward. Additional storm systems will meanwhile work over the Bering Sea as a maritime threat and also spread enhanced winds/precipitation across the region and into western Alaska mainly early-mid week. Energy refresh into the Gulf of Alaska mid-later next week is less predictable for individual systems but seemingly still potent, presenting a continued favorable environment for additional storm genesis. In terms of temperatures, most locations across central and eastern portions of the mainland should enjoy above normal readings next week under the amplified and stabilizing upper ridge, with some areas up to 20 degrees above normal. However, readings should be closer to normal or perhaps slightly below for the western portion of the mainland, the Aleutians and the Southeast Panhandle. Schichtel Hazards: - Heavy precipitation across portions of mainland Alaska, Sun-Tue, Oct 31-Nov 2. - High winds across portions of mainland Alaska, Sun, Oct 31. 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