Beginning at 11 p.m. tomorrow, Feb. 10, westbound Interstate 90 will be reduced to one lane near Bellevue Way then rerouted to the express lanes until 5 a.m. Monday, Feb. 13.

Contractor crews working for Washington State Department of Transportation and Sound Transit will be upgrading operation and safety systems in the westbound Mount Baker and Mercer Island tunnels.

Drivers traveling from the eastside of Lake Washington should plan for lengthy delays along Interstate 405, westbound State Route 520, and westbound I-90.

Closure details:

11 p.m. Friday, Feb. 10, until 5 a.m. Monday, Feb. 13

· All westbound I-90 traffic between Bellevue Way and Rainier Avenue South will shift to the express lanes from 11 p.m. Friday, Feb. 10, until 5 a.m. Monday, Feb. 13.

· Drivers heading to Mercer Island must exit westbound I-90 at East Mercer Way. There are no westbound exits to Mercer Island from the express lanes.

· Those wishing to travel from Mercer Island to Seattle should enter the express lanes at 77th Avenue Southeast or Island Crest Way.

· The westbound I-90 exit to Rainier Avenue South will be closed. Drivers will need to use the Fourth Avenue South exit and follow a signed detour via eastbound I-90.

· Flammable materials will be prohibited on westbound I-90. Drivers hauling flammable cargo must use alternate routes such as I-405 or state routes 520 or 522.