Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 633 PM EDT Sat Oct 09 2021 Valid 12Z Wed Oct 13 2021 - 12Z Sun Oct 17 2021 ...Stormy Pattern Continues from the Aleutians through Southern and Southeast Alaska... ... Guidance and Predictability Assessment... The WPC Alaskan medium range product suite was primarily derived from a composite of very well clustered guidance from the 12 UTC GFS/ECMWF/UKMET and GEFS/ECMWF ensemble means along with the 19 UTC National Blend of Models. WPC product continuity is well maintained in a stormy pattern with above normal predictability. ...Pattern Overview and Weather/Hazard Highlights... Highly energetic and progressive flow aloft will support multiple surface low pressure systems affecting portions of Alaska through the period. A strong low pressure system will exit the eastern Gulf of Alaska by midweek. Additional energies working from an unsettled Bering Sea and Southwest Alaska/AKPen will then act to reinforce a mean low position over the northern Gulf of Alaska that is likely to linger/reform through the weekend and preserve a favorable moisture and enhanced precipitation pattern for south/southeast Alaska. Upstream dynamic stream flow is expected to then drive a deep storm into the Bering Sea by next weekend and downstream energy transfer/triple point low developments should work across the Aleutians/Southwest AK and the AKPen and into an again turbulent Gulf of Alaska to also threaten maritime and southern Alaska by later weekend. Schichtel Additional 3-7 Day Hazard Information can be found on the WPC medium range hazards outlook 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