Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 643 PM EDT Wed Jul 22 2020 Valid 12Z Sun Jul 26 2020 - 12Z Thu Jul 30 2020 ...Overview and Guidance Evaluation... Breakdown/pattern shift across the western/central Pacific has still left the guidance a bit lost in how things evolve next week. With the weakening/splitting upper high over northeastern Russia, lower heights will fill in to its east (near the North Slope). Models and ensembles have had trouble with how this unfolds, whether it will be in one or two pieces, and then where it may go. After perhaps a jump 24 hrs ago, consensus seems to have favored the ensemble means over the deterministic models which favors maintaining the closed low closer to northwestern areas of Alaska. To the south, a system out of the central Pacific may move east-northeastward and slip into the southwest side of an upper low over the Gulf, fall just short and meander to the north, or perhaps both (in some sheared capacity). Consensus still favors its eventual slide eastward around the middle of next week, as the edge of lower heights around the upper low nudges a bit southwestward into the Bering. Confidence remained below average again today due to the many disparate solutions. In light of the uncertainty, favored the 00Z ECMWF ensemble mean over the entirety of the forecast period with support from the 12Z GEFS mean except across the north central Pacific (GEFS mean was still more progressive). Though any deterministic solution was plausible, none could really be favored more than the other given their continuity (or lack thereof). ...Weather Highlights/Threats... Gulf system on Sunday will provide some heavier rain to at least the Panhandle as it moves inland, followed be showers on Monday as the trough follows along. Some heavier rain may be possible over interior locations as well. More scattered rain/showers will accompany and precede the front over northwestern areas next week, and across the Aleutians. Temperatures will generally be below normal over much of the state owing to the upper trough/low. By the end of the period, temperatures should moderate somewhat but the pattern remains quite uncertain. Fracasso 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: - Heavy rain across portions of the Alaska Panhandle and mainland Alaska, Sun-Tue, Jul 26-Jul 28. - Heavy rain across portions of mainland Alaska, Mon-Tue, Jul 27-Jul 28. 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