SEATTLE - Traffic has slowed to a crawl on northbound I-5 near Mercer Street after water flooded onto the freeway.
Washington State Department of Transportation (WSDOT) says an incident response team is on scene, and traffic moving slowly.
Drivers are urged to use caution or find alternate routes.
Officials say water is now pouring into the express lanes, and drivers should expect major delays.
This is a developing story.