Felicia, by George Alec Effinger

Felicia is a Southern-fried not very-thriller. Great bayou location and ambience. Boring, stupid thugs planning a heist. Boring, feckless locals indulging in ennui and adultery. Then at least a hurricane comes and smooshes them all. Slightly interesting in the context of Katrina... The book, written in 1976, harks back to Hurricane Audrey in 1957, which killed 400+ people, and simultaneously captures the knowledge that a major hurricane hitting Louisiana is going to be really bad, and the knowledge that a lot of people will make bad decisions.