Received an email from a friend on the coast yesterday saying the Coho are starting to head into the Straits and to look for them in the North-Central Sound in about a week. Anecdotal info for sure, but its the best info I have. This guy's been pretty reliable in the past.
I just got back from a trip to Hood Canal and they are starting to show. I saw a few fish in a number of different places but they are not in large numbers. I'm lucky enough to have a jet boat and was able to look at a number of beaches. I found a couple of fish around in the Quilcene bay as well. I wouldn't wait more than a week or so before you go because they are starting to show.