Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 544 PM EST Sat Feb 27 2021 Valid 12Z Wed Mar 03 2021 - 12Z Sun Mar 07 2021 ...Overview and Guidance/Uncertainty Assessment... 12 UTC GFS/ECMWF/UKMET/Canadian guidance seem quite well clustered days 4-5 (Wed-Thu) and a composite for that period offers great continuity in an amplified pattern with below normal forecast spread and uncertainty. Pacific energy breaking through the flow differences (mainly into the Gulf of Alaska) and more typical smaller scale guidance variance days 6-8 (Fri-next weekend) elsewhere portends preference for more of a generally compatible GEFS/ECMWF ensemble mean solution. However, opted to keep some deterministic model input in the blend since predictability still seems above normal at mid-larger scales at these longer time frames. WPC continuity is well maintained with this plan. ...Weather/Hazards Highlights... The well defined circulation around a large and deep low will influence the entire Gulf of Alaska through midweek before gradually weakening/reforming to the southeast later next week into next weekend as uncertain Pacific energies break through amplified flow. While a prolonged but tempered maritime threat over the Gulf of Alaska under a mean closed upper low/trough, this overall evolution should limit most associated but waning onshore precipitation to the southeast Panhandle during this period. Meanwhile, energetic upstream energies are slated to work northward into the Bering Sea on the western periphery of a highly amplified midweek upper ridge position. The ridge shunts eastward from the Bering Sea to western mainland and steadily erodes into late week. While the brunt of storm energies focus west of the state, a series of ejecting and weakening systems may bring several rounds of modest precipitation increasingly onshore with time. In this pattern expect a generally benign weather pattern otherwise for much of the North Slope and Interior where below normal temperature linger through late week. Increased flow into the region may act to moderate conditions next weekend. 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