Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 235 PM EDT Sat Jun 29 2019 Valid 12Z Wed Jul 03 2019 - 12Z Sun Jul 07 2019 ...Guidance and Predictability Assessment... The WPC Alaskan medium range product suite was mainly derived from a composite blend of well clustered 12 UTC GFS and the 00 UTC NAEFS/ECMWF/ECMWF ensemble mean along with the 12 UTC National Blend of Models (NBM) Wednesday-Friday. Model and ensemble forecast spread increases next weekend to favor transition for preferece of a NBM, ECMWF and GEFS/NAEFS/ECMWF ensemble mean blended solution. This offers good WPC continuity and was collaborated with local WFOs. ...Weather/Threats Highlights... A low/trough will work across the Bering Sea to offer some heavy rain/wind threat for the Aleutians through midweek. This lead/complex system tends to lift northward over far northeast Russia and into the Arctic later next week. This track is well west of mainland Alaska due to a massive sheilding upper ridge slated to dominate most Alaskan weather through this forecast period. This ridge offers a widespread wildfire and excessive heat risk over the mainland through the upcoming prolonged holiday period. This ridge is impressive with heights building to more than 3 standard deviations above normal that will likely lead to some record temperatures. 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