Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 600 PM EST Fri Nov 25 2022 Valid 12Z Tue Nov 29 2022 - 12Z Sat Dec 03 2022 ...Guidance/Predictability Assessment and Preferences... The 12 UTC GFS/ECMWF/Canadian solutions seem reasonably well clustered Tuesday through Thursday in an overall pattern with reasonable predictability. The 12 UTC UKMET seems an outlier. Prefer to switch to compatible 12 UTC GEFS/ECMWF ensemble means for after that amid growing forecast spread and uncertainty. This forecast strategy has been collaborated with local Alaskan forecast offices. Forecast continuity is less than stellar given embedded system focus variance. ...Weather/Hazards Highlights... Models and ensembles agree to build an amplified upper ridge up over western Alaska next week. The shielding ridge will support more stable and unseasonably warm conditions over much of the mainland eventually outside of the Southeast, with greatest anomalies expected from the western Interior through the North Slope. This solution is well supported in models and ensembles, bolstering forecast confidence. There is more uncertainty with subsequent interactions with Bering Sea systems moving around or in some solutions more bodily into the ridge next week. The aforementioned guidance preferences tend to build and generally maintain the amplified ridge position. Downstream...an area of deepened low pressure is still expected to strengthen off the coast of the Panhandle by Tuesday due to a digging shortwave aloft to the lee of the building upper ridge, but the low track has trended southward. Building high pressure with pressures exceeding 1040 hPa (and temperatures 10 to 20 degrees below average) are expected over southeastern Interior Alaska and the Yukon where low temperatures below -30F are forecast. Cold air will filter southward across the Panhandle early next week. As uncertainty remains with the low track, the forecast details remain less certain than normal. Strong northerly gap winds are expected on Tuesday and Wednesday behind the system over the northern and central Panhandle due to the strong and cold high pressure system. The strong winds will also accompany temperatures around 20+ degrees below average over the Panhandle. Out to the west, the deep layer cyclone in northeast Asia will make slow progress eastward. Gales are possible as a cyclone moves north around its eastern periphery through the western Bering Sea, with another threat for gales in the Bering Sea and Aleutians December 1-3 as another deepened cyclone moves east into and through the Bering Sea, albeit with below normal predictability with specifics. Schichtel Hazards: - High winds across portions of the Alaska Panhandle and mainland Alaska, Tue-Wed, Nov 29-Nov 30. - Much below normal temperatures across portions of the Alaska Panhandle and mainland Alaska, Tue-Thu, Nov 29-Dec 1. 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