If you find yourself in the path of a natural disaster, your first responsibility is protecting lives. Stuff can be replaced. People cannot.
That said, if you have time and can do so safely, there are some things you should do in advance of, for example an oncoming category 4 hurricane, to keep your financial life in order.
Protect your documents
Take digital pictures of any documents you may need after a storm or other natural disaster — insurance policies, passports, birth certificates, and health insurance cards, etc. If possible, you will also want to electronically replicate financial records, medical information, property records, and estate planning documents (like a will or living will).
Store the originals in waterproof bags in locations that are less likely to flood. Or consider a safe deposit box at the bank. There are also free apps on both iOS and Android that make it easy to use your phone to scan text-heavy documents and turn them into PDFs.
Take “before” pictures
When you file an insurance claim, your carrier will generally only pay out if the damage comes from a single, covered event. Sometimes that’s obvious, but sometimes it’s less clear.
Taking pictures of your home and property beforehand can make it easier to show that whatever damage occurred was done by the storm, and was not a result of longer-term wear and tear (which is not covered in most cases). Take pictures of rooms from multiple angles. Open your closets, drawers, and cupboards, and snap some pictures of the contents. If items wash away or are otherwise destroyed, those images will prove that you did in fact possess them.