Alaska Extended Forecast Discussion National Weather Service College Park MD 642 PM EDT Sun Sep 28 2025 Valid 12Z Thu 02 Oct 2025 - 12Z Mon 06 Oct 2025 ...Synoptic Overview... A nearly stationary trough with embedded lows will persist from the Chukotsk Peninsula east across the Bering Strait and over much of the North Slope through the period. A series of longwave troughs moving east to the south of the upper low will keep the weather active across much of mainland Alaska through Monday. A large and strong low will move from the western Bering and Aleutians across the Bering and into Southwest Alaska, which will dominate the weather pattern over all but the Panhandle of Alaska this weekend into early next week. Due to an eastward trend in the guidance, the track of the large Bering low has been adjusted about 100 miles east of where the low was expected to track yesterday. With continued south and eastward shifts, additional track adjustments are likely. ...Guidance Evaluation and Preferences... A blend of 50% 12Z EC, and a 30-20% blend of the 00Z runs of the EC and CMC were used for this forecast period. The deterministic guidance has been in great agreement overall, despite the complexity of the weather pattern. The 00Z runs of the EC and CMC were uncanny in their agreement on the surface features and the track of the large Bering low straight through D8/Monday. However, the 12Z EC maintained that same strength (970s low), but also continued the progression of trending the track of the low eastward with time, which has been the trend in all of the guidance over the past 24 hours or so. The GFS runs, especially the 00Z run were eliminated due to poor agreement with the other guidances. ...Weather/Hazards Highlights... Once again, there are no hazards highlighted on the hazards chart for the first 6 days of October. The large Bering low has some potential of producing winds that near the high-wind/storm force criteria as it's rapidly deepening as it crosses the western and central Aleutians. However, given the remoteness of the Aleutians, their high tolerance for adverse weather, and the short duration when the deepening low will be capable of producing storm force winds, have opted to keep out the threat for now. Heavy rain may impact localized areas, particularly many of the coastal ranges at different times through this weekend and early next week especially, but here too there will not be quite enough moisture available to produce heavy enough precipitation to reach those criteria. The potential for both of these hazards will continue to be monitored. && Wegman 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