Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 400 PM EST Thu Dec 28 2023 Valid 12Z Mon Jan 01 2024 - 12Z Fri Jan 05 2024 ...Wet pattern for the southern fringes of Alaska... ...Windy conditions expected in pockets around the state from early to mid next week, as a large and deep storm moves into the region... ...Overview/Guidance Evaluation/Preferences... A deep layer cyclone is expected to start out near the Aleutians and migrate northward with time as a cold low moves east across eastern Russia. The Aleutians/Bering Sea cyclone gets significantly reinforced by a large and strong cyclone early to mid next week, with some pieces of guidance still dropping its central pressure close to 940 hPa as it approaches and crosses the Aleutians, rather close to December low pressure records for central to northern portions of the archipelago. The 12z GFS was a significant outlier (much farther east) when compared to the other guidance, so weighted its solution minimally into the blend. Most of the grids were weighted towards the agreeable 12z Canadian, 12z ECMWF, 12z NAEFS mean, 00z ECMWF ensemble mean with many grids using an NBM starting point. This should deal with small scale issues, such as the smaller scale but impactful low approaching the AK Peninsula Sunday night (progged to be in the mid 970s for central pressure on approach to the AK Peninsula), the position and depth of the upcoming large and deep cyclone late in the period (explicitly forecast to bottom out in the mid 950s hPa), and the track/depth of the following system approaching the Aleutians mid to late next week. ...Weather/Hazards Highlights... The expected flow pattern leads to some confidence in multiple inches of precipitation (coastal rains, with snow at higher elevations/inland) near south-central AK, particularly January 2, as the large and deep cyclone moves in from the west. Gale to storm-force winds are expected to ring in the New Year across the North Slope, Kotzebue Sound, Norton Sound, the Aleutians, favored locations in southern AK, with hurricane-force winds possible south of the Aleutians, all driven by a potential 90 hPa pressure gradient between the Arctic Ocean and the Aleutians/southern Bering Sea. This storm will also be accompanied by wave/swell threats. Temperatures across western and southern Alaska should warm to above average levels while cold air across the North Slope and eastern interior proves harder to scour out. Roth 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