Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 444 PM EDT Tue Oct 08 2019 Valid 12Z Sat Oct 12 2019 - 12Z Wed Oct 16 2019 Relatively benign weather is expected to start out the medium-range period in Alaska during the weekend before super typhoon Hagibis in the western Pacific transforms into a very robust low pressure system and then moves across the Bering Sea early next week. The latest model guidance agrees pretty well with this overall scenario. Very high winds and significant waves can be expected to overspread the Aleutians on Monday and Tuesday along with the possibility of heavy rain. The WPC Alaska grids were derived using a general compromise of the 00Z EC mean, 06Z GEFS mean, the 12Z GFS and the 00Z ECMWF for Days 4 and 5. The 00Z NAEFS was introduced for Day 5 with less weights on GFS and ECMWF components. Day 7 and 8 grids were comprised of a general blend of the 00Z EC mean, 06Z GEFS mean, and the 00Z NAEFS. Less of the 00Z ECMWF was used than usual since its track of extratropical Hagibis deviates too far from its ensemble mean on Days 7 and 8. On the other hand, the 12Z GFS shows a track that is very agreeable with the 00Z EC mean as well as the 06Z GEFS. Kong 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 Alaska Hazards... - Heavy precipitation across portions of the Alaska Panhandle and mainland Alaska, Fri-Sat, Oct 11-Oct 12. - Heavy precipitation across portions of the Alaska Panhandle and mainland Alaska, Mon-Tue, Oct 14-Oct 15. - High winds across portions of the Aleutians, Sun-Tue, Oct 13-Oct 15. - High significant wave heights for coastal portions of the Aleutians, Sun-Tue, Oct 13-Oct 15. 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