Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 516 PM EDT Sat Aug 31 2024 Valid 12Z Wed Sep 04 2024 - 12Z Sun Sep 08 2024 ...Guidance Evaluation/Preferences... The 12Z model guidance suite shows good agreement with a deep cyclone becoming reinforced in the Gulf of AK and the northeast Pacific by a kicker system moving out of Siberia. The guidance also agrees on an additional cyclone moving from China towards the Bering Sea next weekend. Since agreement was good, used a blend of the 12z GFS, Canadian, ECMWF, and UKMET early on before trending towards 40% of the EC and NAEFS ensemble means late for the pressures, winds, 500 hPa heights, and to some degree the QPF. The remainder of the grids were more 19z NBM based. ...Weather/Hazards Highlights... A cyclone approaches the southern mainland Alaska coast by late Wednesday, while its kicker system approaches from the west/Bering Sea. This will keep conditions wet from South-Central AK into the AK Panhandle as the mid- to upper-level trough remains more or less entrenched. A total of 4-8 inches of QPF is in the grids from Tuesday night into next Sunday across the favored terrain -- not especially unusual for early autumn and reasonably close to continuity. Gale force winds are expected for the coastal and offshore waters as the low approaches, which could lead to higher tides. Storm force gusts can't be ruled out. The incoming low pressure systems across the Bering may also result in periods of rain for western mainland Alaska, accompanied by some stronger winds near the coast. Northern stream shortwaves move through northern AK, keeping the arctic drape near the Brooks Range and cooler conditions across the North Slope. Roth/Hamrick 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