Alaska Extended Forecast Discussion National Weather Service College Park MD 759 PM EDT Thu Oct 30 2025 Valid 12Z Mon 03 Nov 2025 - 12Z Fri 07 Nov 2025 ...Synoptic Overview... The synoptic pattern in the Alaskan domain continues to favor fast-moving cyclones to track west to east through the Aleutians then gradually dissipate over the Gulf of Alaska as a negatively- tilted upper ridge remains stationary across eastern mainland Alaska and further up into the Arctic Ocean in the form of an omega block. ...Guidance Evaluation and Preferences... The ensemble means from the ECMWF, GEFS, and CMC show reasonable agreement on the above-mentioned synoptic pattern evolution through the medium-range period. Much of the uncertainty has to do with the timing of a couple of cyclones that are forecast to move from west to east through the Aleutians from early to middle of next week. The GFS has sped up the fast-moving cyclone that is forecast to pass south of the eastern Aleutians early on Monday in much better agreement with the ECMWF and CMC. For the next cyclone in line, the GFS is near the slow end of the model spread followed by the UKmet, while the ECMWF and CMC are near the fast end of the spectrum moving farther and farther apart with each other to a distance of a few hundred miles to the east by Day 8. These model spread characteristics are similar to those noted in the preceding cyclone. By the end of the medium-range period, both the deterministic and ensemble means show decent agreement on the next significant cyclone to track along the Aleutians with the GFS/GEFS cluster placing the cyclone center just off to the south of the central Aleutians, while the EC/CMC cluster remains farther south and with a much faster forward motion. It was also noted that the 00Z ECMWF solution for this cyclone appears to be an anomaly. This is in contrast to the 12Z ECMWF solution which shows a more classical evolution of an occluding cyclone, which closely resembles that in the 12Z UKmet, placing the center of the cyclone farther to the southeast than the GFS solutions. By Day 8, the EC and CMC move the cyclone much closer to the Alaska Panhandle and the west coast of Canada while the GFS solution of the cyclone has yet to reach the Gulf of Alaska. The Alaska forecast package begins with a general model consensus on Day 4 but is then nudged toward the faster EC and CMC by Day 6 with 50% from the 12Z ECMWF/00Z EC mean, 25% from the 12Z CMC/CMC mean, and 25% from the 12Z GFS/GEFS. This blend yielded an isobaric pattern reasonably compatible with yesterday's WPC forecasts. ...Weather/Hazards Highlights... The medium-range period will begin with a clipper cyclone beginning to swiftly move away to the southeast of the eastern Aleutians early on Monday of next week. Tuesday and Wednesday should see impacts from the next cyclone moving into the Aleutians. The predicted pressure pattern appears to favor high winds on the back side of this system. Therefore, the "High Winds" area has been retained on the WPC Hazards Outlook map for the central to eastern Aleutians on Day 7 Wednesday 11/5 when the center of the cyclone is forecast to pass to the south. Precipitation amounts appear modest due to the speed of the system. Light to locally moderate precipitation will likely linger along the southern and southeastern coastal Alaska as the medium-range period begins. This modest precipitation pattern is forecast to continue through the remainder of the medium-range period as the parade of cyclones arriving from the Pacific are forecast to weaken prior to reaching the ridge axis that is forecast to anchor across eastern mainland Alaska and into Yukon Territories. Temperatures will be mostly above average for much of Alaska to start out the medium-range period. Gradual clearing skies will allow temperatures to return closer to normal for interior mainland Alaska while clouds and precipitation associated with the next cyclone will keep high temperatures cooler than normal across the West and Southwest as next week progresses. Kong 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