Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 518 PM EST Wed Jan 06 2021 Valid 12Z Sun Jan 10 2021 - 12Z Thu Jan 14 2021 ...Major lows offer heavy precipitation and wind/waves threats from the Gulf of Alaska to Southern and Southeast Alaska... ...Guidance/Uncertainty Assessment and Weather/Hazards Highlights... Major lows will spin over the Gulf of Alaska this weekend into next week. Guidance still offers a well defined signal in support of strong system development whose enhanced onshore moisture fetch and circulations are expected to fuel a threat of heavy precipitation and high winds/waves from the Gulf into southern and southeast Alaska. A deepened low is slated to enter the western Gulf from the Aleutians this weekend and energies will interact with a lead Gulf storm to maintain a very stormy pattern with multiple/complex lows into next midweek to focus over the northern Gulf and into southern and southeast Alaska. Given the predicted intensity of these systems, there will be strong winds and hazardous marine conditions. The pattern should also increasingly favor establishment of much above normal temperatures across the Interior this period. The WPC Alaskan product suite was derived from a composite of reasonably well clustered guidance from the 12 UTC GFS/ECMWF/UKMET/Canadian and the 19 UTC National Blend of Models (NBM) Sun-Mon before rapid transition to still compatible GEFS/ECMWF ensemble means guidance and the NBM Tue-next Thu consistent with quick growing forecast spread and less then stellar model embedded system run to run continuity. This solution was collaborated with local Alaskan forecast offices and offshore lows were manually deepened consistent with favorable upper support predictability and to counter weakening effects inherent from the blending process. Schichtel 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 precipitation for southern Alaska and the Alaska Panhandle, Sat-Mon, Jan 9-Jan 11. - High winds for southern Alaska, Sun-Mon, Jan 10-Jan 11. 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