 Northbound 99 is a good alternate route, but it is a bit slow from the stadiums to Mercer Street, and Mercer Street is absolutely jamming between Seattle Center and I-5. In Montlake, eastbound 520, the exit to Montlake Boulevard is closed for the weekend. And heading into downtown, southbound I-5 is running slow from Northgate through the U District. Drive time from Everett to Seattle, 47 minutes.