Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 758 PM EDT Mon Aug 10 2020 Valid 12Z Fri Aug 14 2020 - 12Z Tue Aug 18 2020 ...Guidance Evaluation and Preferences... A mostly progressive pattern will continue across the northern Pacific into next week with a storm track along 50-55N. Farther north, a more uncertain northern stream through the Arctic will waver along and north of 70N. The 12Z ECMWF paired best with the ensembles, but the 12Z GFS/Canadian/UKMET were close enough to use as a deterministic influence at least for the Fri-Sun period. Thereafter, the Canadian appeared too deep and far to the west in the Gulf with troughing while the GFS was likely too deep with troughing over NW Alaska as the ensembles only slowly eroded the upper ridge from western areas (eastern Bering Sea). Nevertheless, still expect troughing to push out of the Bering Strait by the end of the period per the latest guidance, but the models and even ensembles have been inconsistent in the flow north of 65N the past few days. Trended to just and ensemble mean blend by next Tue amid uncertainty in the timing of the next Bering/Aleutian system streaming eastward. ...Weather Highlights/Threats... Lead system Fri-Sat will push through the Gulf and then into the Panhandle by Sunday. Modest to heavier rain is possible as the parent low lingers in the Gulf Monday but the fronts push ashore. Ensemble guidance shows the possibility of several inches of rain over the Panhandle, particularly over southern sections closer to the triple point and moisture-laden air. Next Bering system will bring showers to the Aleutians and across southwestern areas around the same time as a front to the northwest could spark some showers as well. Amounts may be light due to limited moisture. Daytime temperatures will be cooler than normal along southern/southeastern coastal areas but warmer than normal over the Interior and especially western/southwestern areas. Highs in the 70s are forecast. To the north, the North Slope/Brooks Range will trend cooler during the period as heights lower into next week. 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 much of the Alaska Panhandle, Sun-Mon, Aug 16-Aug 17. 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