Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 413 PM EDT Tue Aug 06 2019 Valid 12Z Sat Aug 10 2019 - 12Z Wed Aug 14 2019 An amplified flow pattern will be characterized by an upper low in the Bering Sea and to the northeast of Alaska with stretched ridging across the Bering Strait into western Alaska. Models/ensemble were in decent agreement overall but varied in the handling of each feature (including exiting troughing initially near the Panhandle--though a blend of the 12Z GFS and 00Z ECMWF/Canadian offered a good basis there). To the north, question is how the strong upper low initially near the North Pole translates southeastward toward Banks Island in the Canadian archipelago; specifically, in one piece/bodily (GFS and maybe the UKMET) or in a lead and then following piece (ECMWF/Canadian). Though the ensembles may mute the evolution, they seem to lie more in the camp of the ECMWF/Canadian that sends one vort max Sun/Mon before the second piece shifts the low center farther southeastward. In the Bering Sea, a multi-model/ensemble consensus served fairly well as spread increased only modestly by next Tue but then exponentially by next Wed. Opted to discount any model that brought in a strong cyclone ahead of the ensemble mean consensus which eliminated the GFS/Canadian there. The 00Z ECMWF was acceptable despite its shifts away from the means this weekend as it was still within ensemble tolerance. This pattern favors widespread rain over the Aleutians ahead of the slow-moving front in the Bering Sea over the course of several days. Scattered rain/convection is likely over portions of the interior ahead of the baroclinic zone that will set up on the height gradient south of the Brooks Range. Temperatures will be below average over much of northern/northeaster areas on NW flow aloft, but above average over southwestern Alaska under upper ridging. 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 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