Florida resident here - monitoring the approach of Hurricane Irma. I will gladly evacuate if and when the time comes but wanted to share some Mustachian ways of doing so. I.e. not rushing to the store at the last minute and buying overpriced and wasteful bottled water. And please, if you have anything to add, feel free to do so. This list is geared towards a "bug-out" as opposed to trying to wait it out in your house.
1) Stock up on mason jars (cheap, reusable, and have many uses) and fill one or two dozen with perfectly-good tap water. I bought a dozen for less than $10 and am thus ensured to always have several days of water on hand. Also useful for storing soups, smoothies, and other such foods. I also have a Big Berkey which is a water purifier allowing me to filter rain, and even pond, water. It's a little pricy but I have a feeling it may come in handy over the next couple weeks.
2) Have a cooler and be prepared to toss in some pre-selected frozen and refrigerated foods for when it comes time to hit the road.
3) Have a sleeping bag, tent, and several days of clothing ready to go. Be prepared to spend some nights on the road if hotels are booked up.
4) If you have a spare battery(s) or an auxiliary battery for your cell phone, ensure it is charged up and ready to go. Electricity could be scarce and your cell phone may be a lifeline.
5) Have pet supplies/food ready to go.
6) Keep your car fueled up. I usually drive to nearly empty, but not with a hurricane inbound. In this case I don't go below half in preparation for gas pumps to dry up or, at a minimum, long lines. With a full tank, I have a range of at least 350 miles. Additionally, make sure any maintenance issues are taken care of. For example, you wouldn't want to drive through pouring rain with bad tires or faulty windshield wipers.
7) Get important documents in order. Bring things of vital importance: social security card, credit cards, birth certificates, passport, etc. And with everything else you can't bring, ensure it is waterproofed and stashed away in a file cabinet, or somewhere safe.
8) Non-perishable bulk foods. I have buckets of rice, beans, and flour that will provide weeks of nourishment for myself and others in need.
9) Tools. Portable stove, water purifier, knife, tarps, first aid kit, matches/lighter, etc.
10) CASH. When all of the above fails you, currency is king. Credit cards may not work so be prepared to buy transportation, lodging, food, medicine, etc with good, old-fashioned cash. Take more than you think you will need.
Above all, anticipate and have a plan! If you can stay with a friend or relative out of the disaster zone and get there well ahead of the storm, that is the best route of all. Think about your medical needs, your children, your pets, and the needs of any friends and family that rely on you.