I've caught browns in other states before, but it was the Washington component that made it special for me.
It was just one of those goofy bucket list ideas I think we all have.
BTW; I spent some time fishing northern CA while there for a job quite a few years back. You are fortunate in having all those trout fisheries available down there, especially the rivers on either slope of the Sierra. Longer growing seasons = lots of bigger trout. A lot more Brown trout fisheries down there as well. Remembering this makes me want to go back!