The free fishing weekend offered by the WDFW is this weekend, June 11th and 12th. Trout, salmon, halibut, and more are all on the table.
During those two days, no license will be required to fish or gather shellfish in any waters open to fishing in Washington state. Also, no vehicle use permit will be required during Free Fishing Weekend to park at any of the 600 water-access sites maintained by the Washington Department of Fish and Wildlife (WDFW).
To read more about this, check out http://wdfw.wa.gov/weekender/