I'm from Seattle. But I had immigrated to Canada by the time state of Washington voters legalized the possession of marijuana. Here's an article from the Globe and Mail to remind everyone that crossing the U.S. border INTO a state, is not the same as entering a state. You are entering the U.S. - and when you do, it's the federal laws they care about, not the state laws. In the U.S. possession of marijuana is still a federal crime. So take heed!
Read the Globe article here