Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 618 PM EDT Thu Apr 23 2020 Valid 12Z Mon Apr 27 2020 - 12Z Fri May 01 2020 ...Guidance/Predictability Assessment... The overall pattern across Alaska during the extended forecast period continues to demonstrate average to slightly above average predictability during the early part of the forecast period (days 4-5), and with predictability quickly decreasing during days 6-8. The 12Z ECMWF/CMC showed relatively good consensus with the ensemble means during days 4-5 (Mon-Tue), and a blend of these solutions was used as a forecast starting point during that time frame. This blend maintained excellent forecast continuity, with a couple relatively deep low pressure systems rotating northward into the Gulf of Alaska during that time frame. Starting on day 6 (Wed) and beyond, increasing ensemble means (particularly the ECENS) through time were used to account for the increasing spread. Most guidance continues to show a low pressure system crossing the Aleutians and moving into the western/central Bering Sea by midweek, with a triple point low potentially developing and deepening south of the Alaska Peninsula by Thu-Fri, although spread becomes increasingly large with respect to the specific details of the system structure and timing. ...Weather/Threats Highlights... Two low pressure systems expected rotate over the Gulf of Alaska to off Southeast and Southern Alaska through early next week will bring an increased threat for high winds across portions of the Panhandle, along with locally heavy precipitation. Potential for precipitation/winds should increase across portions of the Aleutians toward the middle of next week in association with the Bering Sea low pressure system. Farther inland, a couple arctic mid-upper level troughs/impulses will work over the North Slope and the Interior through early next week, bringing below average temperatures to portions of the Interior. A relatively weak mid/upper-level ridge axis is forecast to build across the Interior by the middle to latter portion of next week, gradually moderating temperatures some. As a result, the air mass across the Interior and the North Slope will remain quite dry through the forecast period, with little in the way of appreciable precipitation. 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 Hazards: - High winds across portions of the Alaska Panhandle, Sun-Wed, Apr 26-Apr 29. - High winds across portions of the Aleutians, Tue-Wed, Apr 28-Apr 29. 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