Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 514 PM EST Thu Nov 18 2021 Valid 12Z Mon Nov 22 2021 - 12Z Fri Nov 26 2021 ...Below normal temperatures, high winds and heavy precipitation expected across portions of Alaska through the medium range period... ...Overview and Guidance Evaluation/Preferences... The models agree that the longwave trough will remain in place over Alaska however there is increasing noise on the exact location, strengthen and timing of individuals impulses within this flow. Through the extended forecast the CMC and UKMET are favoring a slower progression while the ECWMF and the GFS are faster, however the GFS takes a track further south. The ensemble means are fairly close to their parent solutions but are not as amplified as to be expected. This degree of spread results in a lower confidence forecast but the impacts will keep stronger winds across the southern part of the state along with periods of moderate to heavy precipitation. The initial starting point of the forecast relied on the a blend of the 12Z ECWMF/GFS/UKMET/CMC and included more weights of the ensemble means through the middle and late periods to help dampen the noise in the models. ...Weather/Hazard Highlights... Temperatures are expected to be below or much below normal for a vast majority of the state through the extended forecast. The North Slope will likely remain near, or briefly above seasonal normal through the extended period. Numerous locations observing daily readings as much as 20-30+ degrees below normal. Much of the Interior will have drier conditions while there will be multiple rounds of precipitation, possibly heavy at times, across the Aleutian Chain, the southern coast and the Panhandle. This pattern will also favor flow funneling through the mountain ranges of southern Alaska; which may lead to strong outflow winds. Campbell Additional 3-7 Day Hazard Information can be found on the WPC medium range hazards outlook chart at: https://www.wpc.ncep.noaa.gov/threats/threats.php - Heavy precipitation across portions of the Alaska Panhandle, Sun, Nov 21. - High winds across portions of the Alaska Panhandle and mainland Alaska, Sun-Mon, Nov 21-Nov 22 and Wed-Thu, Nov 24-Nov 25. - Much below normal temperatures across portions of mainland Alaska, Sun-Tue, Nov 21-Nov 23. 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