Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 333 PM EDT Tue Aug 27 2019 Valid 12Z Sat Aug 31 2019 - 12Z Wed Sep 04 2019 The latest mdels and ensembles now more strongly agree that a potent low pressure system will lift across the Aleutians and through the eastern Bering Sea late Saturday into early next week as upper ridging over the eastern mainland slips eastward into Canada. A composite solution primarily derived from the well clustered latest GFS/ECMWF and GEFS/ECMWF ensembles was used for the period from this weekend and Monday. Forecast spread increases by day 7/8, suggesting usage of just the more compatable ensemble means at these longer time frames. This system now seems likely to be a hazard for maritime interests and a downstream heavy weather/precipitation threat across the Aleutians and western/southwestern to southern Alaska considering moisture influx and dynamic support. Schichtel 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 - Heavy rain over portions of mainland Alaska and the Aleutians, Sun-Tue, Sep 1-Sep 3. - High winds over portions of mainland Alaska and the Aleutians, Sun, Sep 1. 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