Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 646 PM EDT Wed Mar 16 2022 Valid 12Z Sun Mar 20 2022 - 12Z Thu Mar 24 2022 ...Pattern Overview... One main feature near Alaska for the medium range period will be a mean upper low with possibly multiple centers of focus at times meandering in the Gulf of Alaska. Energies near the Alaska Peninsula combined with an active storm track across the northeastern Pacific will serve to redevelop and reinforce mean low pressure across the Gulf next week. A series of low pressure systems will bring a sustained period of unsettled weather through the Panhandle and occasionally up into the southern coast for much of the period. A low near the Kamchatka Peninsula will swing a cold front through the Aleutians and lead low focus over the Bering Sea toward southwest AK and possibly even the Gulf of Alaska next week, but a blocky upper ridge setting up near/over Mainland Alaska may limit progression. Downstream in this pattern, upper troughing would also begin to amplify more over an unsettled Mainland as an upper ridge/high settles into northwest AK, albeit with less certainty. ...Guidance/Predictability Assessment... A composite of overall compatible guidance from the 12 UTC GFS/ECMWF/UKMET/Canadian models produces a reasonable solution for Day 4/Sunday, but embedded system variance becomes an issue by days 5-8 especially over the Bering Sea, Gulf of Alaska and the Mainland. The latest GEFS/NAEFS/ECENS means remain decently clustered though in this period, albeit with much less system definition. Accordingly, kept the best clustered ECMWF along with the GEFS/ECMWF/NAEFS means for days 5/6 (Monday/Tuesday) to add a bit more detail consistent with lowering predictability before going full ensembles days 7/8 (next Wednesday/Thursday). ...Weather/Hazard Highlights... Precipitation through much of the period is expected to focus from south-central Alaska to especially southeastern Alaska given the general northern Pacific storm track. The region will experience varying rainfall intensities depending on uncertain surface low progressions. While precipitation does not appear to be very intense overall, recent heavy rain/snow across the area could make it more sensitive to additional impacts. Amounts seem most likely to pick up early next week with expected organized system approach. Farther north, some periods of snow are also possible for the eastern mainland over the weekend and unsettled conditions may persist over the Interior next week if sufficient troughing develops aloft. Meanwhile, slow low/frontal system progression over the Aleutians and the Bering Sea next week may lead to subsequent low re-development and weather focus through southwest AK to the Gulf of Alaska next midweek. There is also some signal, especially from an outlier GFS solution, to support deeper low development over the Bering Sea in this pattern. Schichtel Hazards: No significant hazards are expected over Alaska during this forecast period. 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