Southbound Interstate 5 through downtown Seattle will close Friday night, July 19, and all southbound traffic will use the express lanes through early Saturday morning.

Beginning at 11 p.m. Friday, July 19, until 6 a.m. Saturday, July 20, all southbound lanes will close near the Seattle Convention Center for scheduled maintenance. Travelers should plan for extra travel time or take alternate routes during this closure.

During the closure, Washington State Department of Transportation maintenance crews will conduct fire system testing under the Seattle Convention Center.

People traveling overnight Friday, July 19, in Seattle should expect all southbound I-5 mainline lanes to close from the Stewart Street off-ramp to the Spring Street on-ramp (about milepost 167 to 165). All vehicles using southbound I-5 will need to exit at Stewart Street.

Southbound I-5 ramp closures will include:

– Eastbound Mercer Street on-ramp.

– Yale Avenue/Howell Street on-ramp.

– Union Street off-ramp.

– James Street off-ramp.

During the closure, the I-5  express lanes  will be open for southbound traffic for people traveling through downtown Seattle. The express lane exits in downtown also will remain open. A flammable cargo restriction will be in place. The northbound express lanes will close early to accommodate the southbound mainline closure.