If your government officials tell you to evacuate, I urge you to do so. It as we tell visitors to South Florida, if you stay than its is your own fault for what happens, we will not be liable for you not leaving when you are told to do so (Most Hotels down here actually have a clause or make you sign a document freeing them of liability for individuals staying during a storm).
If you are going to stay, then make sure you have at least 1-2 gallons of water per person and canned food for at least two weeks or so. Battery powered electronics or ones that you manually charge are essential (So are small portable gas stoves).
Make sure you have multiple copies of important documents and that they are in secure place where they will remain dry. Now is also the time to take pictures of you domicile (This also means make sure you read through your insurance policy and make sure it covers hurricane damage, in addition wind and water damage. Be aware also that many companies do not “cover” landslides.)
If you live in an area that floods or that is near large bodies of water, then I’m sorry, but there is a possibility what happened with Katrina may happen again.
That is all,
-Jules