Prognostic Meteorological Discussion
Issued by NWS
Issued by NWS
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190 FXAK02 KWNH 212049 PMDAK Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 349 PM EST Thu Nov 21 2024 Valid 12Z Mon Nov 25 2024 - 12Z Fri Nov 29 2024 ...A shot of snow expected for western and central Alaska this weekend... ...Enhanced gap winds for a cooled Southeast Alaska mid to late next-week... ...Guidance Evaluation/Preferences... The guidance remains in good agreement with a potentially impactful low moving through AK Sunday. The big outlier overall was the 12z Canadian, which showed a much more zonal flow region-wide. When the guidance was most agreeable, used a composite 12z GFS/ECMWF/UKMET/Canadian model blend early on before including more strongly than usual towards the 12z NAEFS/ECMWF ensemble means with time. Most of the grids are 19z NBM weighted, as usual. The QPF was more heavily weighted toward the GFS/ECMWF than the Canadian. ...Weather/Hazards Highlights... A shot of moderate to heavy snow is expected in western and central Alaska this weekend as a cyclone moves by. This system should bring gale-force winds near the Bering Strait. The multi-day trend in the guidance is for ridging across AK to break down and retrograde west into the Bering Sea and eastern Siberia, leading to a cooling trend for southern AK. As is typical, the coldest readings will be on the North Slope and eastern interior. In the wake of the front, gap winds should strengthen/renew near the AK Panhandle early to mid next week. The guidance continues to waffle on cyclone(s) approaching the Aleutians, though there is greater consensus on one approaching late Monday. Gale force winds are still anticipated in the Aleutians, with storm force winds possible across portions of the southern Bering Sea late Monday through Tuesday. 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 $$