"Starting to get a little sense of anxiety, like, OK, am I ready for it?" he said. "Realizing we ain't really ready for a storm. So we're just all thinking about what we gotta do to get in place to get ready for it."

Residents of St. Charles Parish and parts of Jefferson Parish and Plaquemines Parish in Louisiana had been ordered to clear out as well. Some 9,000 residents in Jefferson Parish, Louisiana, were ordered to evacuate Monday morning, along with the towns of Jean Lafitte, Crown Point and Barataria.

"We're worried about tidal surge," Jean Lafitte Mayor Tim Kerner said.

Airports across the region also made plans to shut down as the storm passed. New Orleans will shut its international airport after its last flight Monday night, spokesman Ryan Berni said, while smaller airports in Mississippi, Alabama and Florida also announced closures starting Tuesday.

Louisiana Gov. Bobby Jindal called on residents in coastal parishes prone to flooding to voluntarily evacuate. Even pro football player Courtney Roby of the New Orleans Saints was a little nervous.

"Kinda a scary feeling of uncertainty," he said via Twitter.

Mississippi officials dispatched 1,500 National Guard troops to the state's three southern counties to help with emergency operations, as well as 45 state troopers to ease traffic flow.

The state has distributed 10,000 sandbags to residents ahead of the storm.

"In short, we have done everything in our power to be prepared for the storm," Mississippi Gov. Phil Bryant said.

In the coastal Mississippi city of Pass Christian, people were moving their boats to higher ground and preparing their homes.

"Lookin' like we're gonna be ground zero again," said Daryl Vaught, as he prepared to place sandbags in front of his doors and garage.

"It seems like Katrina just happened yesterday," Vaught told CNN affiliate WDSU. "Hopefully we'll dodge a bullet here this time. I didn't last time."

It appeared Monday that the storm's ferocity would mostly bypass Florida's west coast and the Republican National Convention in Tampa, where the schedule was pushed back a day by organizers over concerns about the storm. The storm passed well west of the city, but flood advisories remained posted around the area Monday evening.