Tri-Cities Region Southeastern Washington Spokane County Central Eastern Washington Yakima County Clark, Klickitat, and Skamania Counties Kittitas County Lewis County Cowlitz, Pacific, and Wahkiakum Counties Olympic Peninsula Pierce County Mason and Thurston Counties Colville - Lake Roosevelt Region North Central Washington King County Kitsap County Snohomish and Island Counties Skagit, Whatcom and San Juan Counties