I'll emphasize what others have mentioned – make sure you have plenty of cash.

My wife works in a regional call center for one of the country's largest credit card issuers. She's spent all day handling non-stop calls from corporate offices seeking help on behalf of employee cardholders trying to use their cards in the stricken areas. Some businesses – hotels, gas stations etc – are refusing to take credit card transactions because, without phone service, they can't obtain automated charge authorizations from credit card issuers.

As we used to say in the banking business: "Cash is king."