Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 613 PM EDT Tue Mar 25 2025 Valid 12Z Sat 29 Mar 2025 - 12Z Wed 02 Apr 2025 ...High wind and blowing snow threat for Northwest Alaska and the North Slope into early next week... ...Guidance/Predictability Assessment... 12 UTC guidance solutions are quite well clustered across and near Alaska Saturday into Monday and a GFS/ECMWF/UKMET/Canadian model blend serves as a fairly detailed forecast starting point, albeit with a seemingly reasonable continuity trend toward energetic system progression across the high latitudes. Lingering guidance differences into later next week are mainly associated with wrapping low interactions over the Gulf of Alaska and to some extent the Bering Sea, but forecast spread and uncertainties are reduced compared to yesterday. Accordingly, prefer a blended model and ensemble mean solution to maintain best possible detail while mitigating small to mid scale differences as consistent with individual system predictability. ...Weather/Hazards Highlights... An amplified and complex mean upper trough position will encompass most of the Gulf of Alaska through this forecast period as surface lows rotate around compact closed upper lows. Most of the rainfall associated with this should hold offshore, although light to some terrain enhanced moderate precipitation will wrap into the southern/southeastern mainland this weekend into next week. Expect some enhanced wind flow well on the backside of these lows into the weekend from the southeast Bering Sea and Alaska Peninsula into the western Gulf of Alaska as well as the far Southeast. Meanwhile, a strong upper ridge will become established over the Aleutians and Bering Sea this week,shifting through western to southern Mainland Alaska into next week. In this pattern, a modest mean upper trough will persist to the lee of the ridge over the Interior this weekend, whose embedded vortices may focus some local snow chances in a cooled environment. Warm air advection along and ahead of a warm front approaching from the Bering Sea will likely then also produce some periods of light snow across portions of the western mainland Sunday, and perhaps be warm enough for some rain closer to the western coastal areas. The guidance signal is then notably stronger and more progressive with the close subsequent approach and inland push of a main trailing upper trough and cold front whose passage across high latitudes is likely support a high wind and blowing snow threat into Monday/Tuesday across Northwest Alaska and the North Slope. Additional system energies in this stream flow are less certain with organizational details, but seems likely to also then work into the area on the heels of the lead system into next midweek. Schichtel 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