Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 150 PM EDT Sun Oct 13 2019 Valid 12Z Thu Oct 17 2019 - 12Z Mon Oct 21 2019 ...Guidance/Predictability Assessment... Model differences remain with embedded small-mid scale weather focusing systems despite a reasonably similar larger scale pattern evolution through medium range time scales. Prefer to include some model with ensemble guidance for better detail and greater system strengths consistent with average predictability, but highly favorable trough/north Pacific jet energy support aloft in an active/stormy pattern. The 12 UTC GFS/00 UTC ECMWF seem most compatable with GEFS/ECMWF ensembles, so the WPC product suite was derived from a composite blend. This solution maintains good WPC continuity as collaborated with the Alaskan NWS forecast offices. ...Weather/Hazards Highlights... The infusion of the potent extratropical remains of western Pacific super typhoon Hagibis into the Bering Sea well offshore western Alaska will prolong unsettled weather as the system meanders under a closed upper trough, with moderate precipitation working into western Alaska. Meanwhile, system energies will consolidate over the Gulf of Alaska into late week and support deepened low developments that will threaten maritime interests and bring enhanced precipitation into southern and southeast Alaska. The lead system may also tap tropical moisture from the remnants of Tropical Storm Ema that is now west of Hawaii. Predictability is lower at longer time frames, but there is still a growing guidance signal for additional deepening low approach from the south of the Aleutians northeast across the Gulf of Alaska next weekend in a continuing stormy pattern. 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