Labor Day traffic is always bad if you're headed in or out of the Puget Sound area, but it will be especially bad for those going over Snoqualmie Pass.

Lanes of westbound Interstate 90 are in a traffic shift between Snoqualmie Summit and North Bend due to a major bridge deck repair. WSDOT says there is no way to shift it back once the project it's started.

WSDOT has released its congestion charts for I-90, Interstate 5, and US 2 ahead of the weekend, so drivers know when routes will be especially bad.

There are several events that will add even more traffic.

- Bumbershoot is at Seattle Center this weekend and the Mariners return home to face the Oakland A's at Safeco Field. The PAX West gaming convention is at the convention center in Seattle all weekend.

- The Evergreen State Fair continues on Monroe, adding traffic on US 2.

- WSU Cougar fans will head over to Pullman for the season opener Saturday and Guns 'N' Roses plays The Gorge Sunday.

- The Washington State Fair in Puyallup opens Friday.

Ferry riders are urged to expect delays as more than 400,000 people are expected to use state ferries between Thursday and Monday. It comes as three ferries are out for repairs and the Fauntleroy-Vashon-Southworth route is down to two boats.

WSDOT says consider walking onto the ferry to cut down on wait times. Sign up for ferry travel alerts to get real-time updates. If you're taking a vehicle to the San Juan Islands, Sidney, BC or Port Townsend/Coupeville routes, it's advised you make a reservation.