First, you could take advantage of electronic record keeping. See if you can receive your bank statements and related documents by email. For paper documents such as W-2s and tax returns, scan them into your computer and save them in an electronic format. You could also create duplicate copies and store them in a separate but safe place.
If you own a business, make sure you create a plan for resuming your operations after a disaster.
Finally, the IRS has disaster loss workbooks for both individual taxpayers and businesses to help you create a record of what you own before disaster strikes.
For more information, check out this page: IRS.gov/disaster.