Not a chance.
Seattle: Trump would be lucky to get 25% of the white vote here.
Tacoma: It'll be much closer, but probably not. He might get 40-45%.
Pierce seems to vote significantly to the right of what you would expect from a Northwest county with a major city in it. Perhaps it's just the non-Tacoma suburb vote being pretty monolithically Republican. I've never seen a breakdown of how Tacoma votes by demographic, so I wouldn't rule out Trump winning there. And for the record, all of the Washingtonian Trump supporters I know personally live in and around Tacoma.