The Tom Tom traffic-data company has ranked Seattle 4th for the worst city in the U.S. for congestion. 

According to Tom Tom's annual study ....

* The average Seattle-area driver wastes 35 minutes in slowdowns for every hour on the road, during commute periods.

* Morning commute times are 48 percent longer than in free-flowing traffic, while afternoon commutes take 70 percent longer. On a 24-hour average, the delay is 25 percent.

* Wednesday mornings and Friday afternoons are the worst times to travel.

Los Angeles was listed as the most congested city in the U.S. 
Seattle was ranked as number 4 in the U.S. and 7 in the world.  Portland was ranked as 13th worst in the world and Rio DeJaneiro was number 1. The TomTom Index is used as a tool for city planners evaluating areas in need of upgrades or changes to improve traffic flow.