Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 508 PM EST Sat Feb 08 2020 Valid 12Z Wed Feb 12 2020 - 12Z Sun Feb 16 2020 ...Guidance and Uncertainty Assessment... Latest models still offer less than stellar run to run continuity and greater than normal forecast spread overall, but there are some signs of improvement. This may be especially evident with the last few runs of the ECMWF that have been in better agreement with at least NAEFS/ECMWF ensemble means during the first half of this medium range forecast period into Thursday morning. Accordingly and after collaboration with the local WFO offices, the forecast starting point for the WPC Alaskan product suite was a blend of the reasonably compatable guidance from the 12 UTC ECMWF and NAEFS/ECMWF ensemble means with the 19 UTC National Blend of Models. Forecaster adjustments were again applied to the blend to add increased detail consistent with individual weather feature predictability and support, especially as per the deepening of offshore lows. ...Weather Pattern and Hazards Highlights... The mid-upper flow pattern next week will feature a mean trough/low over the Aleutians/Bering Sea and a gradually weakening downstream ridge shifting from Southwest Alaska to over the Interior and Southern Alaska. This pattern favors development of a series of potentially deep storms to focus a threat of heavy precipitation/winds/seas across the Aleutians/Bering Sea. Pattern de-amplification/progression over time should spread activity to western Alaska, the Alaska Peninsula/Southwest Alaska and southern Alaska. Meanwhile, lead surface high pressure/cold air settled over the Interior moderates later next week as heights gradually rise as the early weak upper trough shifts eastward into Canada. Arctic stream energies digging into the base of this trough may combine with an uncertain influx of eastward progressing northeast Pacific to Gulf of Alaska trough energies cutting underneath the mainland to meanwhile support a several lows that will present some heavier precipitation threats to the Southeast Panhandle. 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 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