Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 539 PM EST Sat Jan 11 2025 Valid 12Z Wed Jan 15 2025 - 12Z Sun Jan 19 2025 ...General Overview... Active weather will continue through mid-next week for portions of the southern Mainland and Southeast Alaska as a couple weak lows push onshore. Elsewhere, high pressure will dominate the weather pattern through the work week, resulting in low precipitation chances and cooling temperatures to near normal for the interior and northern Alaska. The next impactful weather systems will skirt just south of the Aleutians and gradually lift into the Bering Sea late next week into the weekend, bringing chances for heavy precipitation and gusty winds to the Aleutians, Alaska Peninsula, and southwestern Alaska. ...Model Guidance Assessment... The 12Z suite of model guidance remains in good agreement on the upper level pattern and surface features through mid-next week. Model spread increases significantly after Friday as the models try to resolve the strong systems moving from the Pacific to the Bering Sea and how they interact with each other. The ECMWF shows the best run-to-run consistency while the 12Z GFS came in with a more southern trend than what the consensus has been suggesting. The CMC has fallen more in line with the general consensus today, but still struggles to resolve the low interactions after Friday. For WPC's forecast, a blend of the deterministic GFS/ECMWF/CMC was used for Wednesday and Thursday, with higher weight placed on the ECMWF and GFS. For Friday onward, ensemble means from the GEFS/ECENS/CMCE were added in increasing amounts while the CMC was phased out. Higher weight was placed on the ECMWF/ECENS next weekend due to the greater level of run-to-run-consistency compared to the other model guidance. This blend resulted in a good starting point for the forecast that was close to the ensemble mean solutions. ...Weather/Hazards Highlights... Heavy precipitation will linger in Southcentral and Southeast Alaska through mid-week as two relatively weak low pressure systems track through these regions. Above normal temperatures will make rain the main precipitation type, but wintry mixed precipitation and snow will be possible in the higher elevations. Precipitation chances will gradually decrease across Southeast Alaska later next week as high pressure builds across the Gulf. Precipitation chances will also be low for the interior and northern Alaska under the influence of Arctic high pressure. Precipitation chances will focus on western portions of the state late next week as the next low pressure system tracks along the Aleutians. This system will likely weaken and lose momentum as it heads into high pressure ridging stretching from the Gulf to the Arctic, causing it to become nearly stationary just south of southwestern Alaska. Another strong low pressure system will follow quickly behind the first, tracking into the Bering Sea and pushing a frontal boundary across the Aleutians this weekend. These systems will push an anomalously warm air mass into southwestern Alaska and will result in a prolonged period of heavy precipitation for the eastern Aleutians, Alaska Peninsula, Southcentral and southwestern Alaska. Rain falling on top of snow could enhance snowmelt and lead to localized flooding concerns in some areas, such as Kodiak Island . The strong nature of the low will also likely produce strong gusty winds from the Aleutians to southwestern Alaska late next week into the weekend. Dolan 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