Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 610 PM EDT Tue Jun 30 2020 Valid 12Z Sat Jul 04 2020 - 12Z Wed Jul 08 2020 ...Guidance/Predictability Assessment... The latest guidance continues to show a double low/trough over the Bering Sea with ridging over the North Pacific into the west-central Mainland through the majority of the extended forecast. The 12Z ECWMF hinted that the ridge would break down, allowing shortwave energy to come into the interior- while the rest of the solution maintained the ridging. This may be an early signal that the strength of the ridge may weaken by early next week, however that was the only solution at this time suggesting that evolution. Therefore to maintain continuity, opted to favor a slower progression with the low/trough over the Bering Sea/Aleutians, which would mean a slightly heavier weighting toward the 12Z GFS and its ensemble mean. Other models included in the WPC Alaskan medium range product suite for days 4-8 12Z ECMWF/UKMET/Canadian and NAEFS. ...Overview and Weather/Hazard Highlights... A weakening system over the Bering Sea will slowly move eastward across the North Slope and into the Interior. This will usher in showers with its passage through the region. Meanwhile, with the blocking-like pattern, the deepened low over the Bering Sea will make very little progress; which will keep it offshore through the weekend and into early next week. In turn, this will keep a protracted maritime wind/wave hazard. A lead weather focusing front will be slow to shift over the Aleutians toward western/southwest Alaska and the Alaskan Peninsula. The eastward motion will be inhibited by a warming mainland upper ridge building over the extended holiday weekend. The gradual westward shift of the summer ridge axis more into western and southwest Alaska into early next week leaves room for temperature moderating and unsettling upper trough digging from the Arctic and northwest Canada down through the eastern Interior and Southeast Panhandle. Campbell/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 Hazards: No significant hazards are expected over Alaska during this forecast period. 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