Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 421 PM EDT Tue Aug 20 2019 Valid 12Z Sat Aug 24 2019 - 12Z Wed Aug 28 2019 The upper-level pattern will remain relatively consistent across Alaska during the extended period, with an area of negative height anomalies south of the Aleutians and active westerlies from that region toward the Gulf of Alaska, keeping chances for precipitation relatively high across the Panhandle. Meanwhile, persistent weak ridging across eastern Russia and the Bering Sea should allow negative height anomalies to extend from the Arctic across the northern half of Alaska, with a few shortwaves affecting the North Slope. Began the forecast for the extended period with a multi-model deterministic blend (ECMWF/GFS/CMC) days 4-5, before transitioning to heavier weighting of the ensemble means along with some continued use of the deterministic ECMWF/CMC during days 6-8 due to somewhat better consensus among those solutions relative to the ensembles. This solution shows another low pressure system crossing near/just south of the Alaska Peninsula next Mon-Wed. Spread remains relatively high with respect to this system, however, making the forecast likely the continued subject of future adjustments. Ryan 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 - Heavy rain across much of the Alaska Panhandle, Fri-Sun, Aug 23-Aug 25. 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