I’m in Nevada City, CA (~2.5hr northeast of SF) and saw the notification maybe 3-5 seconds prior. Everyone in my workplace stepped out of their offices and said they all saw the notification before the building started shaking.
If you are inside, stay inside and get under a sturdy piece of furniture, such as your office desk. If you are outside, run the hell away from structures and trees toward the most open space you can get to.
Also, I don't run into many HN folks in/from this area, let's get in touch and maybe meet up sometime.