Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 423 PM EDT Sun May 27 2018 Valid 12Z Thu May 31 2018 - 12Z Mon Jun 4 2018 Recent runs of the ECMWF and GFS looked reasonably aligned with the large scale pattern over Alaska through Friday night. However, a fair amount of mesoscale variability among ensemble members suggests there is still quite a bit of uncertainty with the details of the forecast, so the WPC forecast still incorporated some continuity and ensemble means into the Day 4-6 (Thursday to Saturday) blend. By next Sunday, the GFS is much more amplified with the upper ridge over Alaska and farther south with a second upper low entering the Gulf of Alaska, and without one piece of deterministic guidance offering much stability with the pattern, the WPC forecast was heavily weighted towards ensemble means for the second half of the forecast period. WPC medium range Alaskan products including 500mb, surface fronts/pressures progs and sensible weather grids can be found at: http://www.wpc.ncep.noaa.gov/alaska/ak_5dayfcst500_wbg.gif www.wpc.ncep.noaa.gov/alaska/akmedr.shtml http://www.wpc.ncep.noaa.gov/alaska/ak_5km_gridsbody.html Hamrick