The open ocean of the Washington coast is primarily threatened by to two types of tsunamis. The first is called a near-field tsunami generated from earthquakes throughout the Cascadia Subduction Zone. Depending on where you are: on the coast, or inland near Port Townsend, it can be 30 minutes to over an hour until tsunami waves arrive. In that case, a person on the beach would have to react on their own to recognize natural ques such as ground shaking or quick recession of water away from the beach. The second tsunami source threatening the coast of Washington is a far field event caused by an earthquake on the Pacific Ocean margin, such as Alaska or Russia. There would be hours before the event showed. The sirens would go off and you would have support from local emergency management to evacuate the area. The overall risks to each community are in the hands of the communities themselves.