NEW ORLEANS - New Orleans cast a wary eye toward tropical storm Chris today and put the final touches on a reaction plan that could empty the city which last evacuated after Hurricane Katrina.

"I'm scared to go through another one," said forklift driver Inos Jones, 50, who stayed through Katrina last August until he was rescued. "If they have another hurricane, you can just shut Louisiana for good."

The National Hurricane Centre projected that the centre of Chris could strengthen to hurricane force within 36 hours.

Local forecasters in New Orleans said the storm could enter the Gulf of Mexico and head toward the city over the weekend. But its path remained uncertain.

Mayor Ray Nagin told a news conference the city administration had a reaction room ready and was watching to see if the storm entered the Gulf on Saturday.

"If it does, we will be on serious high alert," he said.

The city's mandatory evacuation plan aims to move all residents out of the city rather than offer a shelter of last resort, hoping to avoid replicating last year's mistakes when thousands of people were trapped by the rising waters as 80 per cent of the city flooded.

Hurricane Katrina killed 1,336 people in five states.

The city is lining up drivers for evacuation. Nagin said National Guard troops could also step in if necessary.

Nagin said he was worried about the thousands of people in government-issue trailers, which cannot stand winds above 64-80kph who would need extra time to get out.

Not all residents were nervous. "I got too much work to worry. I'd rather face the rain than face my boss," said 17-year-old construction worker Kalen Wilson.