Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 643 PM EST Mon Jan 4 2021 Valid 12Z Fri Jan 8 2021 - 12Z Tue Jan 12 2021 ...Overview and Guidance/Uncertainty Assessment... A rather stormy and unsettled weather pattern is expected to continue across the Aleutians and the Gulf of Alaska region for the weekend and extending into early next week. There will be a weakening storm system that will initially be over the northern Gulf region on Friday. By this weekend, the models are indicating a strong system approaching the British Columbia coast and southeast Panhandle region. Meanwhile, another strong storm crossing the Aleutians this weekend is expected to enter the western Gulf and likely merge with the southeastern Gulf system by Sunday night, and then become a large and broad low pressure gyre by early next week. There is some longitudinal spread with the CMC to the northwest of the means, and the GFS to the southeast. Once the pattern becomes more amplified and defined by Monday, the deterministic CMC/EC/GFS are in above average agreement for the Day 6-8 time period, and this justified a general blend of those models, along with some of the ensemble means, as a starting point in the forecast process. ...Weather/Hazards Highlights... The multiple northeastern Pacific/Gulf systems should bring numerous rounds of moderate to occasionally heavy precipitation to areas in the general vicinity of the southern coast and Panhandle region. The greatest rain and snowfall amounts are expected to be between the Kenai Peninsula and the southeast Panhandle, with several inches of rainfall possible near the coast over the 5 day period. Given the predicted intensity of these systems, there will likely be strong winds and hazardous marine conditions. Meanwhile, strengthening winds and increasing precipitation should reach the western Aleutians by late Friday, and then extend across the rest of the islands during the weekend as the associated storm system progresses eastward. The upper level pattern will favor the establishment of generally above normal temperatures across most areas during the medium range period. Locations over the northwestern mainland will likely be closer to normal readings. The above normal anomalies for low temps should generally be greater than those for highs. Hamrick 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 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