Alaska Extended Forecast Discussion NWS Weather Prediction Center College Park MD 558 PM EST Mon Feb 13 2023 Valid 12Z Fri Feb 17 2023 - 12Z Tue Feb 21 2023 ...Overview... A closed low/trough will be present over the Bering/North Pacific and send shortwave energy toward the Southwest Mainland/eastern Aleutians; which may lead to high winds for portions of western/southwestern Alaska by the end of the week/weekend. Another upper-level trough developing in the northwest Pacific will track eastward while deepening into a closed low through the middle and latter periods. With a potentially strong low pressure at the surface parts of Alaska with could have high winds and light to moderate precipitation. This appears most likely spread across the Aleutians and keeping cloudiness and some precipitation across the southern coast and Southeast. ...Model Guidance/Predictability Assessment... For days now the models have started our fairly clustered but with time the solutions become diffuse, thus lowering confidence on any specifics with a few features. The mean consensus continues to show a shortwave/surface low tracking toward West/Southwest Alaska and then lifting northeastward through the Interior. In general this feature may usher in strong winds across parts of the western mainland along with light to moderate precipitation into central Mainland. Previous runs of the guidance has the new closed low/upper trough fizzling out by/after Day 6 as is nears the western Aleutians; however the Sunday's runs kept this feature together albeit in split camps. Today's run kept this feature together however the clustering did not improve. The ECWMF/CMC continues to favors a West/Northwest position while GFS is much further East/Southeast; furthermore, the EC ensemble and GEFS have a closer position to that of the ECWMF/CMC. By Day 8 another low there is a diffuse pattern featuring a low south of the far western Aleutian islands with another low well south of the central Aleutians and high pressure over the eastern Pacific/southeast Gulf of Alaska. All in all, this is average confidence pattern. The WPC leaned toward a combination of the 06Z/12Z GFS, 12Z ECMWF, 12Z CMC and the GEFS/EC Ensemble means. Leaned more toward the ECWMF due to run to run consistency but did include varying degrees of the CMC and both the 06Z and 12Z runs of the GFS due to their more pronounced timing, depth and location differences. ...Weather/Hazard Highlights... Most of the active weather will focus from the Aleutians to the Southeast through the course of the extended period; however light to moderate precipitation will expand across portions of Southwest and Central Alaska by the end of the week and into the weekend. In proximity to the surface low, strong to high winds may move across parts of the West/Southwest through Friday. Addition rounds of precipitation across the south-central and southeast portion of the state as an upper troughing and surface low pressure tracking eastward likely through the northern Pacific. The specifics with this system still remain a bit uncertain however the model guidance has trended to better consensus on the evolution by Day 7 and 8. Winds are likely to affect the Aleutians as a frontal system stemming from a Bering Sea low comes in, which could spread farther east by the latter half of the week. Temperatures are expected to trend closer to seasonal average by the end of the week and hold fairly steady. Campbell Hazards: - High winds across portions of mainland Alaska, Thu-Fri, Feb 16-Feb 17. 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