Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 300 PM EST Mon Nov 11 2019 Valid 12Z Fri Nov 15 2019 - 12Z Tue Nov 19 2019 Models showed reasonably good agreement during days 4-5 with a filling low pressure system across the Gulf of Alaska Fri and another multi-centered low pressure system entering the Gulf from the south on Sat. Additionally, the GFS has come more in line with the general consensus with respect to Arctic shortwave energy that is forecast to cut off across the eastern Bering Sea Thu night-Fri, after previously showing a much deeper system than other guidance. The ECMWF and GFS were both reasonably close to the overall consensus during this time frame, and a blend of these two solutions was used for days 4-5. By day 6 (Sun), the second Gulf system is forecast to reach Southeast Alaska and push inland, while another low pressure system crosses the Aleutians. One significant player by late in the medium range will be what is now Tropical Depression 26W, forecast to be a typhoon as it recurves east of Japan by later this week. 26W should undergo extratropical transition by late this weekend as it interacts with the aforementioned low pressure system near the Aleutians. Model solutions diverge and become quite chaotic on the specific evolution of this feature and the potential interaction between the post-tropical cyclone and the mid-latitude low pressure system. Nonetheless, there is the potential for a deepening low pressure system to pass near the Aleutians by next Mon, potentially crossing the Alaska Peninsula or moving into the Gulf of Alaska by Mon. Given that confidence was quite low in the specifics during days 6-8, opted to go heavily toward ECENS/NAEFS ensemble means during that time frame. Ryan Additional 3-7 Day Hazard information can be found on the WPC medium range hazards chart at: https://www.wpc.ncep.noaa.gov/threats/threats.php - Much above normal temperatures across portions of mainland alaska, Mon, Nov 18. 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