Aurora Avenue North will be closed from the Battery Street Tunnel to Valley Street this weekend for construction, from 11:59 p.m. Friday until 5 a.m. Monday.
Northbound traffic on the Alaskan Way Viaduct will be detoured off the Western Avenue exit, before approaching South Lake Union. Southbound drivers will be encouraged to detour at North 85th Street, long before the full closure.
Crews will be shifting four road lanes of Aurora onto a new bridge that crosses above Mercer Street, which will also be closed.
Another closure is planned Dec. 14-15, to demolish the old Aurora-Mercer overpass.