Alaska Extended Forecast Discussion National Weather Service College Park MD 628 PM EST Sat Nov 22 2025 Valid 12Z Wed 26 Nov 2025 - 12Z Sun 30 Nov 2025 ...Overview... The medium range period begins Wednesday with an upper ridge over the Gulf, an Arctic upper high, and a weak shortwave or upper low cutting across the interior fro East to West. A weak low pressure system south of the Aleutians will weaken as it gets forced northward into the Bering Sea late next week. By next weekend, a very amplified pattern will develop over Alaska with an anomalously strong ridge over the Gulf and eastern Mainland, and another surface low lifting north towards the Aleutians. This may bring a period of moderate to heavy rain or snow to parts of the Southern Coast and AK Peninsula region. ...Guidance Evaluation and Preferences... There is generally good agreement on the large scale pattern through much of the period, but still plenty of uncertainty in the details which impacts sensible weather and especially heavy rainfall potential across the Southern Coast region next weekend. In the beginning of the period, there was some uncertainty in the evolution over/near the Gulf region with how quickly ridging will finally build in. The CMC was quicker to build in the anomalous ridge, but the GFS and especially the UKMET and ECMWF suggest a weak shortwave cuts through ahead of and real ridge building. Despite this, a general model blend, anchored by the ECMWF, served as a good starting point for the Days 4 and 5 forecast. By Friday, a deeper surface low should begin to lift towards the eastern Aleutians and by the weekend there is a lot of uncertainty in the details and timing of this low. The models are in agreement on it's presence, so felt like a ensemble mean/deterministic model (ECMWF) blend worked well for now. ...Weather/Hazards Highlights... With weak low pressure systems and persistant onshore flow, the central Aleutians through the Southern Coast and Panhandle region will remain unsettled with light rain or snow mid to late next week, but nothing particularly hazardous or heavy. Onshore flow will strengthen ahead of the deepening low pressure system into the Aleutians region next weekend to promote more widespread moderate to heavy precipitation especially across the Alaska Peninsula to Kenai region and Kodiak Island. It was enough of a signal in the models to introduce a heavy precipitation area on todays WPC hazards chart valid next Friday into Saturday. Lighter rain may spread into parts of southwest Alaska and the Panhandle region as well with this system. For the most part, much of the interior mainland may be mostly dry through the period. Temperatures could be below normal to start the period across Eastern Alaska and the Southeast. The entire state however should trend warmer into next weekend as anomalous upper ridging builds in. Widespread anomalous 10 to 20+ degrees above normal are possible especially for Western/Central Alaska and the North Slope. Southern parts of the Panhandle may stay closer to normal or even slightly below. Santorelli 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