Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 458 PM EST Tue Nov 19 2024 Valid 12Z Sat Nov 23 2024 - 12Z Wed Nov 27 2024 ...Wet pattern for western AK and the Aleutians with enhanced gap winds for a cooled Southeast Alaska... ...Guidance Evaluation/Preferences... Model spread has grown with the blocking ridge parked near and south of AK aloft. The ECMWF remains the most aggressive in knocking it down, albeit temporarily. The guidance change has led to increased cooling when compared to continuity in central AK. To account for uncertainty and try to take the edge of the 12z ECMWF closed cyclone moving through AK, used a composite 12z GFS/ECMWF/UKMET/Canadian model blend early on before including some of the 12z NAEFS/ECMWF ensemble mean with time. Most of the grids are 19z NBM weighted, as usual, though went without including the 12z ECMWF due to its outlier status with the system transiting AK early to mid period -- some 12z ECMWF ensemble mean was blended in with the NBM. The QPF was equal parts deterministic and NBM. ...Weather/Hazards Highlights... Some snow is seen across interior Alaska at times this period as a cold front and disturbance aloft move by. A warm core high should shield southern AK from much cooling or precipitation until another deep cyclone or two approach the Aleutians from the southwest early to mid next week. As is typical, the coldest readings will be on the North Slope and eastern interior, though the eastern interior will see fluctuations due to the frontal passage. With systems moving through the Aleutians and the Bering Sea around the west side of the ridge, western AK and in particular the Aleutians and AK Peninsula should be the wettest late this week through early next week. Roth 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 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