Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 645 PM EDT Thu Mar 12 2020 Valid 12Z Mon Mar 16 2020 - 12Z Fri Mar 20 2020 ...Overview and Guidance/Predictability Assessment... A series of potentially powerful Pacific systems will lift through a highly unsettled Aleutians and Bering Sea and work inland into the Interior/North Slope, temporarily breaking through a lead upper level ridge position. These systems offer potential for the development of deep lows and well organized frontal structure that would focus winds and widespread and enhanced/widespread precipitation. Temperatures will warm across the region over the next week, but remain cold enough to support widespread and locally heavy wintery weather in many areas. System timings seem fairly periodic with main effects occuring roughly every two days in this pattern next week. Meanwhile underneath, additional system trough/jet energies will break eastward through the southern portion of a lead main upper ridge position next week over the Gulf of Alaska in a pattern with more modest precipitation potential for southwest/southern/southeast Alaska. ...Weather Highlights/Threats... The WPC Alaskan product suite valid for Monday/Tuesday were primarily derived from a composite blend of reasonably well clustered guidance from the 12 UTC GFS/ECMWF/UKMET/Canadian models, WPC continuity, and the 19 UTC National Blend of Models (NBM). Forecast spread increases quickly with embedded systems in the 6-8 day timeframe, so it seems prudent to rely mostly on more consistent and seemingly reasonable GFS/NAEFS and ECMWF ensemble mean guidance and the NBM at these longer time frames. Predictability overall seems near average. 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 snow across portions of western Alaska, Thu, Mar 19. - High winds across western to northwestern Alaska, Wed-Thu, Mar 18-Mar 19. - High winds across portions of the Aleutians, Tue-Wed, Mar 17-Mar 18. - Much above normal temperatures across western and northern Alaska, Sun-Thu, Mar 15-Mar 19. 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