Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 705 PM EDT Sun Jul 02 2023 Valid 12Z Thu Jul 06 2023 - 12Z Mon Jul 10 2023 ...Synoptic Overview and Guidance/Evaluation Preferences... A low pressure system over the eastern Aleutians should weaken as it lifts north into Bristol Bay late this week. The associated upper level trough/shortwave will slide across Mainland Alaska next weekend. More uncertain energy rounding the base of troughing over the Arctic/Siberia may try to move into the Bering Sea around next weekend with a second weaker upper low moving towards the western Aleutians around Sunday-Monday. Upper level ridging may try to build back in across the Gulf and into western Alaska next Monday. The 12z ECMWF is noticeably displaced to the northeast with the initial low moving into Bristol Bay on Thursday, and faster/more amplified with troughing across the Mainland next weekend. The 12z ECMWF is also more aggressive with additional energy behind this across the Bering Sea. Late in the period, the ECMWF suggests troughing will hang around over at least the Western Mainland (with an upper low over the Gulf), but the GFS and CMC attempt to bring ridging back into the region at this time. This also translates to issues in strength of the next low pressure system towards the Western Aleutians and into the Bering Sea next Sunday and Monday. The ensemble means seem to favor the GFS and CMC, but in a much weaker/more washed out fashion. The WPC blend favors the GFS/CMC over the ECMWF, with greater contributions from the ensemble means later in the period to help smooth out some of the smaller scale details which are impossible to resolve at this time frame. Overall, this maintains fairly good continuity with the previous shift as well. ...Weather/Hazards highlights... The initial low into Bristol Bay and associated troughing in Western Alaska will create a fairly wet pattern for much of coastal and western Alaska into the Brooks Range through the weekend with several inches of rain possible in some of the higher terrain and areas closer to the southern Coast. Upper troughing should keep the western and central Interior and into the Brooks Range cooler, with daytime highs 10-20 degrees below normal for this time of the year. Temperatures in parts of the eastern Interior and into Southeast Alaska should however stay above normal and warm (with temperatures into the 70s and 80s). Santorelli Additional 3-7 Day Hazard Information can be found on the WPC medium range hazards outlook 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