Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 243 PM EDT Sun May 12 2019 Valid 12Z Thu May 16 2019 - 12Z Mon May 20 2019 A complicated cacophony of compact closed centers of circulation will center over the Gulf of Alaska/northeast Pacific late next week through next weekend. The models/ensembles have devolved into worse agreement as the forecast has introduced more players in the otherwise predictable longwave flow, thus favoring the ensemble means over any single deterministic solution. However, even the ensemble means again moved away from otherwise good agreement 24 hrs ago with small timing differences increasing with time. The ECMWF ensemble mean offered the most stability (despite its washed out appearance) as the GEFS mean again has shown some noticeable shifts with each cycle (i.e., 00Z --> 06Z). Using the 00Z ECMWF ensemble mean as a best starting point, the deterministic models that stayed closer to it and continuity (still a reasonable solution) were the 00Z ECMWF and UKMET. The recent GFSs (including the FV3-GFS) were too different in timing to yield a sensible blend, but their solutions were not necessarily unreasonable. A blend of just the 00Z ECMWF/ECMWF ensemble mean forged the day 6-8 forecast with low confidence in details. Precipitation will favor areas along/south of 60N as waves of precipitation rotate counterclockwise around areas of low pressure that they themselves will rotate counterclockwise in the Gulf. Interior/northern areas will remain mostly precipitation-free except around next Fri/Sat as a weakness aloft passes westward out of Canada. Fracasso 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