Alaska Extended Forecast Discussion National Weather Service College Park MD 724 PM EDT Thu Oct 16 2025 Valid 12Z Mon 20 Oct 2025 - 12Z Fri 24 Oct 2025 ...High winds and heavy precipitation for the Aleutians and Alaska Peninsula this weekend and possibly spreading eastward... ...Overview... A broad upper low is forecast to be in place atop eastern Siberia into the Bering Sea into early next week, with rounds of potentially impactful cyclones on its periphery. A large and deep surface low is forecast to pass near the Aleutians and Alaska Peninsula Sunday and bring heavy rain/precipitation and high winds then tracking east across the Gulf of Alaska Monday-Tuesday. It may bring the heavy precipitation into Southcentral and Southeast Alaska. Another wave of upper troughing and a weaker surface low look to track near the Aleutians once again early next week, and then settle into the Gulf of Alaska while the broad cyclone aloft reorients a bit east into Bering Sea by midweek. ...Guidance Evaluation/Preferences... Guidance continues to depict a notably strong surface low (generally in the 950s or 960s mb) crossing the Aleutians just prior to the start of the extended period. This feature will usher in high winds with it, although the associated QPF has trended more offshore thus reducing the threat for heavy rain for portion of the Aleutians, AKPen and southcentral Mainland. The low system is progged to move east across the Gulf of Alaska. Unlike the previous runs, there are intermittent time steps where the CMC has trended toward the track/evolution of the GFS and thus has some degree of usability. Upstream, another surface low looks to track east from the southern tip of the Kamchatka Peninsula early next week. Models have this low's central pressure generally in the low 980s. The low looks to arrive to Kodiak Island and the Gulf of Alaska by Tuesday and then persist there through Wednesday and Thursday. The preferred blend leaned toward a GFS/EC and their means for the extended period with small, intermittent inclusions of the CMC. ...Weather/Hazards Highlights... The latest guidance has backed off on QPF amounts for the Aleutians to the Alaska Peninsula, keeping the highest amounts over the Gulf. However, these areas can expect high winds with the strong surface low for the start of the week. Precipitation should spread into Southeast Alaska (the Panhandle) regardless, beginning Monday. The second low will provide some moderate rain to the Aleutians and AKPen again into Monday, likely reaching Southcentral and Southeast by Tuesday with moderate to heavy amounts. The slower- moving pattern by the middle of next week will be favorable for moisture streaming into Southeast Alaska for multiple rounds of precipitation next week. Thus will continue to monitor if this deserves a hazard area on the Day 3-7 Hazards chart, despite the high criteria for this time of year since the region can handle a lot of precipitation. Farther north across the Mainland, most areas should stay mainly dry early next week (after a few rain and snow showers early Sunday), until Tuesday and Wednesday when coverage of light precipitation may increase as energy aloft gets closer and funnels some weak moisture ahead of it. Lower elevation areas of the Mainland will mostly be above average temperatures (especially for lows) through the period, with chillier temperatures in the Brooks and Alaska Ranges. The Lower Kuskokwim delta may cool to slightly below average by Wednesday- Thursday as energy aloft moves in. Southeast Alaska should be generally near average for temperatures in the 40s and low 50s. Campbell/Tate 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