First thing to remember, don't panic. Second, you should have several different levels of preparedness.
Do you have a small bag in each car with necessities?
Do you have a kit in your office with some food and basic supplies in case you're stuck there for a day or two?
Next, how about a duffel bag or large backpack in the apartment that you can grab and leave in 1 minute that will keep you going for 3 days?
Finally, lets say you are stuck at home for 10 days in a massive blizzard. Most people can do that with food, but if power is out, can you cook, maybe on a gas grill on your deck? And as for water, think about one of the water buffaloes that you fill in your bathtub as soon as you are aware of an incident occurring.