Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 619 PM EDT Sat May 08 2021 Valid 12Z Wed May 12 2021 - 12Z Sun May 16 2021 ...Guidance/Predictability Assessment... 12 UTC GFS/ECMWF/UKMET/Canadian solutions seem reasonably well clustered and consistent days 4-6 (Wed-Fri) and enjoy ample ensemble support, bolstering forecast confidence. The 12 UTC GFS/ECMWF remain best clustered with the 12 UTC GEFS/ECMWF ensemble means and the 19 UTC National Blend of Models for next weekend as well and a composite blend seems to generally produce a good forecast starting point consistent with a pattern with overall above normal predictability. This strategy maintains great WPC product continuity. ...Weather/Threats Highlights... Upper trough energies and lead/complex precipitation focusing surface lows/frontal weather systems will work across the Gulf of Alaska to southern/southeastern Alaska into mid-later next week, undercutting a warming and stabilizing interior upper ridge. Meanwhile upstream, amplified/closed upper trough energy is slated to track over the southern Bering Sea/Aleutians and deepening low pressure will support increasingly unsettled maritime conditions and inland feeding enhanced rains and winds across the region. Activity is expected to translate downstream into Southwest Alaska, the Alaskan Peninsula, Kodiak Island, the Gulf of Alaska then southern and southeast Alaska heading into next weekend with steady main system progression and lead triple point low developments. 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