Your visit is right inline with the start of the pink salmon run. I believe there is an estimated 6 million pinks to return to Salish Sea rivers. A six weight rod will work just fine as these fish average about 4 to 7 pounds. Do a search on fly fishing for pink salmon. Also you might try searching washingtonflyfishing.com and/or asking a question or two on the board there.
If you can get up north to the Skagit I may be able to provide a day on the river. The Skagit is about 60, 70 miles north of downtown Seattle or a little over an hour drive on I5.
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