Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 657 PM EST Fri Jan 28 2022 Valid 12Z Tue Feb 1 2022 - 12Z Sat Feb 5 2022 ...Overview... The Alaska domain will likely experience a blocky upper level pattern through the first few days of February with a ridge axis remaining anchored in place over the eastern Gulf region and also across eastern Siberia, with a col over western mainland Alaska. A large upper level gyre is expected just south of the western Aleutians with multiple shortwaves rotating northward towards the eastern Aleutians and the Alaska/Kenai peninsulas with several rounds of rain/snow expected. ...Guidance/Uncertainty Assessment... Overall, the 12Z guidance and the ensemble means are in relatively decent agreement on the overall synoptic scale pattern across mainland Alaska and western Canada through about Thursday. Similar to the past few days, the greatest model and forecast uncertainty resides over the Bering, Aleutians, and North Pacific with multiple shortwave perturbations pivoting around a large scale upper level gyre, with significant timing differences with the individual shortwaves as they lift northward over the Aleutians and then the Bering. A weaker disturbance makes it farther east over the northern Gulf region by the middle of next week, and the deterministic guidance supports this scenario. Given the model uncertainties over the Bering/Aleutians later in the forecast period, an ensemble mean approach appears prudent as a starting point for now. ...Weather/Hazard Highlights... Arctic high pressure slowly weakens during the medium range period, but keeps most of mainland Alaska dry and cold. Snow showers and gusty winds are likely for the southern coast from the Kenai Peninsula to the southeast panhandle as a weak low pressure system develops along a stationary boundary over the northern Gulf. Some of this snow could be heavy at times on Thursday with greater onshore flow expected. Meanwhile, a few storm systems are expected to bring the potential for periods of wet and windy weather to the Aleutians through this period. Most of the Interior should be near to below average for temperatures, and generally above average for south-central Alaska and the Aleutians. Hamrick Hazards: - Heavy precipitation across portions of the Alaska Panhandle and mainland Alaska, Thu-Fri, Feb 3-Feb 4. - Heavy precipitation across portions of mainland Alaska and the Aleutians, Mon-Thu, Jan 31-Feb 3. - High winds across portions of the Aleutians, Mon-Wed, Jan 31-Feb 2. 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