Earthquake.

I live in an apt. building built in the 1950's with an overhang parking garage (the worst design imaginable). I try and park on the street but most of the time there's no space so I have to park under my apt. (literally directly underneath my bedroom.) I keep water and a kit in the car and of course the usual home provisions but because earthquakes are so unpredictable I try to keep my plans flexible. I'm working off the premise that when TSHTF, if my apartment is still standing, the rest should be relatively easy.