https://earthquake.usgs.gov/earthquakes/map/?extent=3.0747,-165.14648&extent=62.26792,-24.96094The Juan De Fuca plate sits off of the west coast of Oregon, Washington and Vancouver Canada. As you can see, there has been a series of earthquakes on the western side of the plate. The eastern side of the plate is the Cascadia Subduction zone. In late January 1700, the Cascadia subduction slipped, creating a 9.1 quake with damage seen in Japan ten years ago, with most of the damage coming from the resulting tsunami. If you know anyone that lives west of I-5 in the areas I mentioned, you might want to give them a call and let them know to be prepared. When the quake happens, the tsunami happens 15 minutes later. They will have 15 minutes to get to high ground.
To be more comprehensive, when quakes happen on the west side of the plate, it creates more pressure on the east side (subduction zone). These quakes today may be an outlier, but this is a scary and very real threat.