Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 552 PM EST Sat Mar 04 2023 Valid 12Z Wed Mar 08 2023 - 12Z Sun Mar 12 2023 ...Model Guidance/Predictability Assessment... Models continue to offer less than stellar run to run continuity, but the 12 UTC ECMWF now seems best supported by GEFS/ECMWF ensembles Wednesday into Thursday as systems work into and dig to the lee of an upper ridge built over the mainland. Systems in the pattern become more chaotic thereafter in retrogressive transition, lending to quick transition to a mostly ensemble mean blended solution. ...Pattern Overview and Weather/Hazard Highlights... A weakening plume of moisture is forecast may linger within a relatively narrow zone from the eastern Aleutians northward into western/northwestern Alaska through midweek on the western periphery of an initially amplified upper ridge over mainland Alaska as low pressure waves track from south to north across the Bering Sea and into the Arctic Ocean. Snow is expected to be the main precipitation type across western to northwestern Alaska, but mixed precipitation may occur up through southern coastal areas of the Seward Peninsula. A slow drying trend is forecast for the precipitation-affected areas through the middle of and into late next week as guidance continues to indicate further break down of the highly amplified pattern. However, periods of snow can be more expected to move across the North Slope/Brooks Range from mid to late week with uncertain but potentially dynamic shortwave trough energy/height fall passages as a piece of the anomalous ridge breaks off into an upper-level high over southern Alaska, then shifts slowly westward into the Bering Sea by late week. Unsettling energies digging to the lee of the upper ridge position and continued flow into later periods suggests that eastern Alaska and especially the Panhandle will experience temperatures much colder than normal thanks to the Arctic high pressure system centered over Yukon. This pattern is forecast to persist along with only modest precipitation opportunities. 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