Alaska Extended Forecast Discussion...UPDATED National Weather Service College Park MD 659 PM EDT Mon Jul 7 2025 Valid 12Z Fri 11 Jul 2025 - 12Z Tue 15 Jul 2025 ...Synoptic Overview... Initially, troughing will be in place to the northeast while an Arctic high nudges into the region from the northwest. This high pressure ridging will gradually extend into the northern Mainland over the weekend into early next week. To the south, a series of lows/shortwaves will move along the Aleutians into the Gulf resulting in potentially heavy rain in Southeast Alaska on Thursday and Friday. By the weekend, a broad area of low pressure should consolidate over the Bering/Aleutians and several shortwaves are expected to pivot around this feature, bringing renewed rain chances for the southern Mainland and Southeast Alaska. The upper low should gradually move towards the Gulf, and surface low pressure lingering in the vicinity of the Alaskan Peninsula early next week may also create heavy rain chances for Southwest and Southcentral Alaska. ...Guidance Evaluation and Preferences... Overall, there is relatively good model agreement on the upper level pattern with an expected amount of differences in the details of individual systems. The period with the greatest model spread is early next week (typical at this time frame) as the upper low shifts from the Bering towards the Gulf and interacts with upper level shortwaves and the Arctic high. These interactions will influence the timing and track of this feature and will affect sensible weather impacts as well. The GFS is on the slower side of guidance while the ECMWF is on the faster side, but neither solution is unreasonable. For now, the WPC forecast favors a middle ground solution, falling between the GFS and ECMWF. WPC's forecast was composed of a near even blend of the deterministic GFS/CMC/ECMWF/UKMET for July 11-12, which represents the pattern well given good model agreement early on. For July 13-15, ensemble means from the GEFS/CMCE/ECENS were added in increasing amounts to smooth out model differences and produce a middle of the road solution. Smaller contributions from the GFS/CMC/ECMWF were maintained through the end of the forecast period to retain details of individual systems. ...Weather/Hazards Highlights... An Arctic front will sink south towards northeastern Alaska late this week then move into northwestern Canada this weekend. Troughing is expected to persist to the northeast into Saturday, then a high pressure ridge will move in from the northwest and settle over northern portions of the state. High pressure will linger in the vicinity through Monday, then shift more into Canada. This will result in a period of below normal temperatures late this week followed by a gradual warming trend back to near normal temperatures. The Arctic air mass may bring dry, gusty conditions to the north, which may result in heightened fire weather concerns. To the south, the series of lows moving into the Gulf will bring persistent rain chances from Southcentral to Southeast Alaska late this week, and locally heavy rainfall will be possible. Precipitation amounts are forecast to decrease across these regions over the weekend and early next week, but troughing along the coast will likely support daily chances for at least light showers. Early next week, the focus for heavy precipitation should shift to Southwest and Southcentral Alaska as low pressure lingers near the Alaskan Peninsula, resulting in scattered to widespread showers. Dolan 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