The Mississippi Emergency Management Agency said that its emergency management center would remain open around the clock, beginning at 8 a.m. Friday, the Jackson Clarion-Ledger reported.

Gustav is expected to hit the Gulf Coast early Tuesday as a Category 3 hurricane. The storm was headed for Jamaica late Thursday.

Barbour urged Mississippi residents to "take this storm seriously," telling them "now is the time to prepare yourself, your family and your friends."

"One of the most important lessons we learned after Hurricane Katrina was that there is no substitute for awareness and self-help, especially in the days before a hurricane is predicted to hit," he said.

About 2,800 emergency trailers are still serving as homes for victims of Hurricane Katrina, which struck three years ago. They must be evacuated before Gustav arrives.