Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 634 PM EDT Mon Mar 25 2024 Valid 12Z Fri Mar 29 2024 - 12Z Tue Apr 02 2024 ...Late Week/Holiday Weekend One-Two Storm Punch to offer Wind/Wave/Coastal Flooding and/or Snow/Rain Threats from the Aleutians through Southwest and Southern Alaska... ...Guidance Evaluation and Preferences... The 12 UTC GFS/ECMWF/UKMET/Canadian model solutions are broadly clustered into Easter morning with decent ensemble support. A favored model composite highlights the most predictable detail in highly energetic flow, despite pesky but mostly smaller scale differences. Prefer the still compatible GEFS/ECMWF ensemble means onward into next week amid growing system and stream phasing differences issues. This mainly includes conditions for a cooling Mainland as Arctic stream upper trough energy works to dig southward and potential/eventual phasing to some degree with Pacific stream energies into the Gulf of Alaska and associated cold low developments offshore to monitor. ...Pattern Overview and Weather/Hazards Highlights... There remains a good guidance signal that an amplified upper trough and an associated surface low pressure system will track/develop from a position currently by Japan to across the northwest Pacific to near the Aleutians Thursday to offer turbulent maritime conditions and swirling winds and rains. This storm and frontal system is likely to work northeastward into the Bering Sea and support high winds/waves and potential associated coastal flooding threats up the coast of western/Southwest Alaska Friday into Saturday before losing this influence offshore. Meanwhile, guidance has strongly jumped on robust development of a trailing frontal wave back over the north Pacific that is now slated to lift northward toward the Alaska Peninsula Saturday as a potentially potent storm/high winds threats, with subsequent track into Southwest Alaska and into an unsettled/snowy Interior while slowly weakening. This energetic scenario would focus a heavy snow threat over portions of Southwest Alaska and into the Alaska Range. There would also be a heavy rainfall and more inland/terrain heavy snow threats as fueled by a channeled/deepened lead Pacific moisture feed up into the Alaska Peninsula/Kodiak Island and SouthCentral Alaska, and to a much lesser extent Southeast Alaska through the 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