Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 309 PM EST Fri Jan 4 2019 Valid 12Z Tue Jan 8 2019 - 12Z Sat Jan 12 2019 Model ensemble means continue to show a fast and progressive flow pattern with energetic shortwaves progressing eastward across the Northeast Pacific into late next week. The preferred storm track remains well south of mainland Alaska, with a major oceanic storm expected south of the Aleutians during the second half of the forecast period. Over mainland Alaska, the ECMWF and EC mean indicate that a cold upper low will slowly retrograde westward across northern Alaska into northeastern Siberia through next week. This will keep a frigid air mass in place, especially across northern Alaska. The GFS is also on board with this overall pattern with some detail differences. Given that the ECMWF/EC mean has handled the synoptic pattern the best for areas south of Alaska lately, we will continue to lean toward the ECMWF solutions. Therefore, the latest WPC Alaskan grids were based on a weighted consensus from these model solutions: 00Z EC mean, 12Z ECMWF, 12Z CMC, and 12Z GFS with a preference to the ECMWF/EC mean. This model preference means that the frigid temperatures across Alaska are forecast to linger well into next week. Nevertheless, a slow warming trend is indicated toward the latter part of next week across central and southern Alaska. In terms of precipitation, northern Alaska will remain dry. Farther south, occasional snow mixing with rain is expected across the Aleutians due to the proximity of the storm track. Kong/Hamrick WPC medium range Alaskan products including 500mb, surface fronts/pressures progs and sensible weather grids can be found at: http://www.wpc.ncep.noaa.gov/alaska/ak_5dayfcst500_wbg.gif http://www.wpc.ncep.noaa.gov/alaska/akmedr.shtml http://www.wpc.ncep.noaa.gov/alaska/ak_5km_gridsbody.html