Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 646 PM EST Tue Dec 07 2021 Valid 12Z Sat Dec 11 2021 - 12Z Wed Dec 15 2021 ...Another Major Storm for Alaska... ...Overview and Guidance Evaluation/Preferences and Weather/Hazard Highlights... A deep low pressure system over the Bering Sea will track toward the Southwest Alaska, the Alaska Peninsula/Kodiak Island before redeveloping into a potent low near the Kenai Peninsula by Friday. This feature will impact a major of the state by ushering in strong wind, cold temperatures and/or scattered to widespread precipitation. Another system is expected follow, tracking over the eastern Gulf of Alaska over the weekend/early next week; which will spread the threat of high winds, Gulf waves along with heavy coastal rains and terrain enhanced heavy snows from south-central Alaska to the southeast Panhandle. Much below normal temperatures will be settled in over much of the southern half of the state after it the system passes. For specifics on the expected hazards, refer to latest WPC Day 3-7 Hazards Outlook product listed and linked below. The global models (GFS, CMC, UKMET and ECWMF) have a decent clustering with the initial low near the Bering Sea through about 12Z on December 13th before the spread increases. Like the previous runs, the GFS/ECMWF remain best clustered and in line with ensembles. There continues to be slowly growing guidance signal to support additional Bering Sea storm genesis into these longer time frames, but with an uncertain downstream track and re-development toward Alaska. To maintain a since of continuity, the WPC preferred blend had a starting point of the 12Z GFS/CMC/UKMET/ECWMF/EC ensemble means that trended toward more inclusion of the EC ensembles and GEFS mean by the later periods. Campbell Hazards: - Heavy precipitation along the Alaska Panhandle to portions of the south coast of Alaska, Fri, Dec 10. - High winds across portions of southwestern Alaska and into the Aleutians, Sat-Sun, Dec 11-Dec 12. - High winds across central Aleutians, Fri, Dec 10. - Much below normal temperatures across the southern half of mainland Alaska and the Alaska Peninsula, Sat-Mon, Dec 11-Dec 13. 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