Alaska Extended Forecast Discussion...amended NWS Weather Prediction Center College Park MD 812 PM EST Wed Nov 23 2022 Valid 12Z Sunn Nov 27 2022 - 12Z Thu Dec 1 2022 ...General Overview... The start of the extended forecast period on Sunday will be featured with an upper level ridge across the eastern Aleutians and the southwestern mainland, and the low near the southeast Panhandle will be weakening and moving away. However, a second low pressure system is progged to reach the Panhandle region on Tuesday with heavy precipitation and gusty winds. Meanwhile, arctic high pressure governs the overall weather pattern across much of the Interior going into the early-middle part of next week. ...Guidance/Predictability Assessment and Preferences... The 12Z model guidance suite, along with the 18Z GFS, indicates the low over the southern portion of the southeast Panhandle steadily weakening, and also agree well on the upper ridge over the western Gulf region. Shortwave energy from the Bering then breaks through the ridge and forms a new low over the northern Gulf early next week, with the ECMWF indicating a stronger storm compared to the GFS that is in a similar location. The CMC differs here by being a bit farther offshore with the low and is also more progressive as the low tracks southeastward along the British Columbia coast. Model differences become substantial by Wednesday/Thursday across much of the North Pacific and forecast confidence falls to below average. The WPC fronts/pressures forecast was primarily derived from a multi-deterministic blend for Sunday and Monday, followed by an increase of the EC/GEFS means through the middle of the week with about 70% ensemble means by Wednesday-Thursday. ...Weather/Hazards Highlights... The ongoing coastal low near the southeast Panhandle region will be weakening by Sunday, but this will likely be replaced by a second storm forming over the northern Gulf late Monday and lasting through Tuesday as it also drops towards the southeast. This will likely be close enough to produce a few inches of QPF across the windward terrain of the Panhandle, with heavy snow for the coastal mountains. Light to moderate snow is also likely on Monday across portions of southern mainland Alaska with moist onshore flow. Strong gap winds are likely on the backside of this low owing to a tight pressure gradient with a big surface high across the Interior. It will be this same high that will result in a bitterly cold air mass across much of east-central Alaska, with the coldest readings across the Yukon Flats with some -20s and -30s possible! Hamrick Hazards: - Heavy snow across portions of the Alaska Panhandle, Mon-Tue, Nov 28-Nov 29. - High winds across portions of the Alaska Panhandle and southern mainland Alaska, Tue-Wed, Nov 29-Nov 30. 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