We didn’t feel it, but after belatedly seeing an alert about a 3.3 quake centered under south Vashon Island at 11:10 pm, we heard from someone on Alki who did. (And if you did, you can tell the U.S. Geological Survey about it here.) Here’s the quake’s infopage; note that the basics about the quake might change by the time you see this – the magnitude was upgraded from 3.2 to 3.3 just while we were writing, and the depth was revised from 13 to 15 miles. This map showing quake history in the area suggests Vashon Island has been quake-free for quite some years, till this.