Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 424 PM EDT Tue Oct 22 2019 Valid 12Z Sat Oct 26 2019 - 12Z Wed Oct 30 2019 The amplification of the ridge over the east/central portion of the state will increase to +3 standard deviations from the mean by Sunday morning as the deep extratropical evolution of Neoguri reaches and lingers near the Aleutians; which will then hold fairly steady through the end of the forecast period. Deep tropical moisture will transport northward over the Aleutians/western Alaska, where a tight pressure gradients setups up between the trough and ridge. Moisture anomalies initially will be 1.5 to 2.5 standard deviations above the mean and will surge to 4 standard deviations above the mean by Sunday. Expect highest precipitation totals along southward/southeastward-facing terrain along the Alaska Peninsula and southern coast of the mainland. Somewhat less extreme but likely still very significant precipitation should extend into other portions of the southern and western mainland. Extratropical Neoguri will bring areas of strong winds and high waves as well. The GFS continues to be the most progressive solution amongst the guidance and was deemed an outlier. The ECWMF and the ensemble means were better clustered with the evolution of extratropical Neoguri late this week. With such a strong ridge anchored over the state, this further supports a slower/deeper track over the Bering Sea/Aleutians/southern Mainland. Campbell 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 Alaska Hazards... - Heavy precipitation across portions of mainland Alaska and the Aleutians, Fri-Sat, Oct 25-Oct 26. - Heavy precipitation across portions of mainland Alaska and the Aleutians, Sat-Tue, Oct 26-Oct 29. - High winds across portions of mainland Alaska and the Aleutians, Fri-Sun, Oct 25-Oct 27. - High winds across portions of mainland Alaska, Sun-Mon, Oct 27-Oct 28. - High significant wave heights for coastal portions of mainland Alaska and the Aleutians, Fri-Mon, Oct 25-Oct 28. 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