Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 348 PM EDT Sat Aug 31 2019 Valid 12Z Wed Sep 04 2019 - 12Z Sun Sep 08 2019 There remains good guidance signal into mid-later next week for organized low system development to mainly effect western Alaska and 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 then AKpen/Southwest AK still has support for a pattern favorable for additional organized low system developments and widespread heavy weather/rainfall potential mid-later next week and next weekend along with lead southern stream low lift up into the Gulf of Alaska. Forecast spread has improved into the day 7-8 timeframe, so a composite blend of the GFS/ECMWF and GEFS/ECMWF ensembles seems reasonable in a period of above 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 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