Living in SoCal, I am always mindful of The Big One, a 7+ earthquake, and so I try and remain ready for that. Also on my list are wildfires spreading into town and various forms of social unrest. Since I get outdoors a fair amount, I try and equip myself appropriately for those occasions, which most likely would require an extra night or two in the woods and some measure of medical treatment. I try to be ready to help others in local incidents - help with first aid before the fire department arrives, and the like. Basically, if you are ready for an earthquake, you are ready for just about anything.
Primarily I keep my outdoor gear organized and ready to use (not always successfully, I might add). If the house is destroyed, we will set up in the yard and camp out. Under the bed I keep a crowbar, a working light, a jumsuit, and old sneakers, along with the gas shutoff tool. I always know where my glasses are. Food for about a month for the entire family is always on hand. We all review our plans periodically.
Over the years, we have had little mini events which I feel keep us sharp - we were on the edge of the Northridge quake, doing without electricity for a day. Ten years ago, a wildfire burned within a quarter mile of our house, and I had the van loaded and ready to drive away if necessary. We felt good about the priority list we had developed for such an event. First aid training and gear comes in handy all the time.
I do occasional trips to the Channel Islands - two coming up next month - and water safety is an issue. The vessels I travel on are USCG certified, properly equipped, and I know the crews are competent, so I don't worry much there. I always have my personal PSK items within reach when at sea, especially a Leatherman tool. The papers today are carrying a story about the recovery of a missing fishing vessel - the crew of two is lost. It makes me thoughtful, because I have seen the boat around the harbor, although I did not know the crew.
You gotta be prepared...