Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 655 PM EDT Wed Jul 01 2020 Valid 12Z Sun Jul 05 2020 - 12Z Thu Jul 09 2020 ...Guidance/Predictability Assessment... Model guidance has a trend of increasing spread through the extended period that is lowering forecast confidence in the regards of amplitude and axis of the blocking ridge pattern. The last three runs of the ECWMF have consecutively shifted the ridge axis to the west which allows the mid/upper low over the Arctic to drift closer to far Northeast Mainland/Yukon. The GFS runs do show the amplitude of the ridge lessen with time but maintains the low over the Arctic/Canada further east. The CMC favors the ECWMF evolution, while the UKMET consistently splits the differences between the ECWMF and GFS solutions. At this time, still favor a slower progression with the low/trough over the Bering Sea/Aleutians and hanging onto the ridge longer. This equated to including the ensemble means earlier in the forecast and a heavier weighting toward the 6/12Z GFS. ...Overview and Weather/Hazard Highlights... Shower activity will accompany a front as it slowly moves across the North Slope and into the Interior. Parts of West/Southwest Alaska and central Mainland could see rain through the week. 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 coming week. 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 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