Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 524 PM EST Mon Mar 01 2021 Valid 12Z Fri Mar 05 2021 - 12Z Tue Mar 09 2021 ...Overview and Guidance/Uncertainty Assessment... Larger scale flow transition is overall decently handled in guidance across medium range time scales, but the models struggle with embedded system emphasis and complex interactions that seem better resolved with the steadier ensemble means this weekend into next week. Accordingly, favor a solution close to the 12 UTC GFS/ECMWF Day 4/Friday before transition Saturday to the compatible 12 UTC GEFS/ECMWF ensemble means and 19 UTC National Blend of Models Sunday-next Tuesday. This forecast strategy maintains good WPC product continuity in a pattern with near average overall predictability. ...Weather/Hazards Highlights... A closed mean upper vortex will anchor over northeast Russia days 4-8. While the brunt of storm energies focus from an unsettled Bering Sea up into the Arctic Ocean, a series of ejecting and weakening systems on the eastern periphery of the large circulation will bring several rounds of moderate snows increasingly onshore into western/northwestern Alaska and the Interior in active flow. These systems also offer some maritime threats and some potential for coastal high winds and associated wave/ice effects. Meanwhile, ample upper trough energies extending down over the Bering and Aleutians are slated to break eastward into an also unsettled Gulf of Alaska. This will support low developments over the Gulf with lead focus digging through the region Friday-Sunday and an additional potential period slated for early next week. These systems offer a moderate maritime threat and the potential for enhanced precipitation onshore mainly for the AKPen/Kodiak Island and into southern Alaska. Schichtel Hazards: - High winds across portions of mainland Alaska and the Aleutians, Fri, Mar 5. - High winds across portions of mainland Alaska, Sun, Mar 7. 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 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