A colleague (and host) from Helsinki says the winter climate in Helsinki is very similar to Seattle’s — in both cases moderated by a large body of water. (I’ve heard the same about Ketchikan, AK, too but you don’t have to go far inland before it changes dramatically.)
We lived on an island across Gastineau Channel from Juneau, and though we had snow, we also had the Pacific Current.
I can’t recall the channel ever being frozen.