Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 625 PM EST Mon Jan 27 2020 Valid 12Z Fri Jan 31 2020 - 12Z Tue Feb 04 2020 ...Deep freeze continues for much of Alaska... ...Low pressure system to bring windy/rainy conditions to the Aleutians... Models and ensembles were in good overall agreement through the weekend as troughing moves into the Bering Sea and out of the Gulf. Heights will continue to be below average nearly state-wide which will help maintain the cold pattern for the next week or so. A blend of the latest 12Z models served as a good starting point with better than average agreement and generally expected detail differences. By next Sun-Tue, models continued to indicate a robust area of low pressure 950s-960s mb) crossing the western Aleutians wits its occluded front lifting into the Bering and eventually Bristol Bay. This will bring in milder air to the eastern islands and parts of coastal areas to the east with southerly flow, changing pre-frontal snow to rain but still maintaining snow inland. The guidance diverged on how to unravel the system, including triple point development and possible movement into the Gulf, and whether or not any sfc wave may develop and move into the Gulf along the cold front. For now, trended toward the much smoother ensemble means as those feature as that lead time have low predictability. Deterministic model solutions were plausible but not consistent among runs. To the north, troughing will gradually be replaced by westerly flow aloft as ridging builds across the Alaska Range but an upper low meanders in the Arctic Ocean around 80N. Temperatures in the North Slope will stay several degrees below average as areas to the south moderate from 15-25 below average to within several degrees of average. Precipitation will be favored along the coast from the Aleutians across to the Panhandle, but mostly focused with the Bering/Aleutians system. Several inches of rain (some onset snow) are possible along the coast and southeastward-facing areas. Fracasso Additional 3-7 Day Hazard information can be found on the WPC medium range hazards chart at: https://www.wpc.ncep.noaa.gov/threats/threats.php Hazards: - Heavy precipitation across portions of the Alaska Panhandle, mainland Alaska, and the Aleutians, Sat-Mon, Feb 1-Feb 3. - Heavy precipitation across portions of the Alaska Panhandle, Thu-Fri, Jan 30-Jan 31. - High winds across portions of mainland Alaska and the Aleutians, Sat-Sun, Feb 1-Feb 2. - High winds across portions of the Alaska Panhandle, Thu, Jan 30. - Much below normal temperatures across portions of mainland Alaska, Thu-Sat, Jan 30-Feb 1. - Much below normal temperatures across portions of mainland Alaska, Fri-Mon, Jan 31-Feb 3. 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