Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 708 PM EDT Tue May 10 2022 Valid 12Z Sat May 14 2022 - 12Z Wed May 18 2022 ...Overview and Guidance/Predictability Assessment... The upper flow pattern across Alaska over the next week looks to remain quite amplified/blocky as highlighted by strong ridging over the Bering Sea and an elongated/multi-stream trough from the Mainland into the Gulf of Alaska laden with high latitude system energies from the Arctic. A strong shortwave dropping south through the mainland leads to a large weekend closed trough/low over the Gulf. Additional shortwave energies digging to the lee of the ridge over a unsettled eastern Bering Sea and mainland should subsequently also act to reinforce low pressure in the Gulf. The 12 UTC GFS/ECMWF and GEFS/ECMWF ensemble means overall seem reasonably well clustered over the weekend despite lingering smaller scale system differences, bolstering forecast confidence in the larger scale pattern. Embedded system confidence is not as good considering the more varied Canadian and UKMET solutions and recent run to run guidance continuity issues, especially but not limited from northern Alaska through the Interior into the Gulf. Model differences seem to grow enough there and over the Bering and Gulf by next week to justify a transition to an ensemble mean forecast approach. This forecast plan maintains decent WPC Alaskan product continuity. ...Weather and Hazard Highlights... Increased light and periods of moderate precipitation are likely to organize across portions of Northern/Interior Alaska this weekend into next week with each shifting southward as upper disturbances and several well organized surface fronts work across the area. There is some threat for high winds, mainly over the western mainland, as pressure gradients tighten with system passages. Even though temperatures across much of the state are expected to be near to below seasonal spring values, some river flooding, significant in some places, is expected to be ongoing associated with snow melt and ice jams. Offshore to the south, regeneration through the weekend and into early-mid next week of a well organized upper low/trough and associated surface system position over the Gulf of Alaska will also favor a periodic focus for moderate and terrain enhanced precipitation over Southeast Alaska/Panhandle. Schichtel Hazards: - Flooding possible across portions of mainland Alaska, Fri-Sat, May 13-May 14. - High winds across portions of mainland Alaska, Mon, May 16. 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