In California (the CCP), our regular disasters tend to be flooding in places during the annual winter rains, wildfires in the forests and hills during the regular hot dry summers, and the occasional big earthquakes, in that order of regularity.
Here, you really need a medium sized backpack for every person with 3 day's food, water, TP, soap, toothpaste, washrag, and deodorant. Also sneakers. Those are critical items. Most people have something like that ready to go at home. Some people keep it in their car. Some really well prepared people also have a kit like this at work as well.
For us the main issue is normally sheltering in place if possible, or evacuation if necessary. Flooding and fires normally warrant evacuation unfortunately. If you can shelter in place in your home, then you have access to all your regular food supplies, and all you need in addition is a camp stove and matches and fuel for it, or you can siphon gas out of your car for the stove, if it will take it.
For sheltering in place, it is worth it to have a stashed water supply in jugs of some kind. These can also be grabbed on your way out if you need to evacuate. I have found that it takes 1 gallon of water per day for me for drinking and washing. I store tap water in jugs, and I use a big backpacking water filter to filter it with before drinking. For washing there is no problem with stored tap water.
The interesting thing about tap water that has been stored is the 1/4 inch layer of gunk that accumulates at the bottom over time. So you thought your tap water was clean huh? It always needs to be filtered further.
Since I am also a seasonal hunter, I like to go camping in the fall, and I have a complete campsite stashed in the closet by the front door which I can quickly load into my SUV if I need to evacuate. This includes tarp, tent, rain fly, mattresses, sleeping bags, pillows, lawn chairs, reclining lawn chairs, beach umbrella, and other gear. Might as well go in style if you need to.
When I hunt, I also backpack, so I keep the backpack ready to go during the off season as well, stored in the front closet with the other gear.
I hunt with rifle, bow, and/or revolver, so those are always ready to go, kept in my gun safe.
I defend the castle with CZ 97B and Mossberg 590 and those are in the gun safe when not on my person.
I like to keep a year's supply of rice, a month's supply of water, 2000 rounds of ammo (which normally lasts 1 year for me), cleaning gear and extra cleaning gear, binos, compass, range finder, hiking boots, hiking shoes, and sneakers all ready to go to be thrown into the SUV if need be. Also highway roadmap booklets of California, Nevada, Utah and Colorado. All depends on how far one needs to go to get away from the "problem," but you will need road maps.
Flooding you can usually see coming, by watching The Weather Channel local forecasts. I watch these every night, mostly so that I can plan my week.
Fires sometimes catch you by complete surprise, but if there is smoke in your county then you should be wary.
Earthquakes are sent by Neptune Himself and there is never any warning for those, but usually you can shelter in place afterwards, unless your neighborhood catches fire like Northridge or San Francisco.
Just in case something really big might happen, I also keep 4 huge empty gasoline cans (plastic) in the front closet, if something is headed our way, foreseeable, and I need to gas up enough to get me all the way out of California and half way across Oregon or Nevada as well. I would fill these as soon as the likelihood developed.
The last time I went tactical was around 10 pm one night when the big tsunami hit Japan, and the back end of it was headed our way across the Pacific. I live at an elevation of 20 ft, and those waves can get as high as 50 ft. Most of California was already in bed and was not paying attention to the news. I was already at the local gas station down the street filling my 4 gas cans.
Fortunately when that tsunami hit California it only rose to about 4 ft -- no problem. Gasoline keeps for several months, although not long enough to store. It would be too dangerous to store it anyway. Diesel is more safe to store, that's why most industrial generators are Diesel not gasoline. (Somebody here will probably disagree with that and give a long dissertation missive.)
Be prepared.