Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 303 PM EDT Fri Aug 30 2019 Valid 12Z Tue Sep 03 2019 - 12Z Sat Sep 07 2019 Models and ensembles still agree that a potent short range low pressure system slated to lift over the eastern Bering Sea will gradually weaken early-mid next week. The system will offer a lingering maritime hazard and heavy weather/precipitation threat into western/southwestern Alaska and across southern/southeastern Alaska with downtream energy/system transfer. There also remains a decent upstrean early-midweek guidance signal for a second low system to develop on the heels of the lead storm to mainly effect maritime interests over the central and northern Bering Sea/Bering Strait. A blend of the quite well clustered and reasonable 12 UTC GFS and ECMWF was used in this period of above average forecast confidence. Upper trough amplification back into the Aleutians and southern Bering Sea/AKpen still seems to support a pattern favorable for additional organized low system developments and heavy weather/rainfall potential into mid-later next week along with lead southern stream low lift up into the Gulf of Alaska. Forecast spread has improved some in this day 6-8 timeframe, so a composite blend of the GFS/ECMWF and GEFS/ECMWF ensembles seems reasonable in a period of at least average predictability. 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, Mon, Sep 2. - High winds over portions of mainland Alaska and the Aleutians, Mon, Sep 2. 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