Hurricane Frances - now a tropical storm over the Gulf of Mexico - could return to menace the US, having wreaked havoc in Florida over the weekend.
The hurricane brought Florida to a near-standstill
At least four people died as a result of the high winds and heavy rain that have lashed the Bahamas and Florida.
Though now downgraded to a tropical storm, forecasters warn the bad weather could worsen over the Gulf of Mexico and strike south-eastern US afresh.
Nearly three million people have left their homes because of the hurricane.
About 5.8m people are without electricity because of damage to power lines, Florida state officials said.
Having eased after its assault on the east coast, the storm was last said to be centred about 240km (150 miles) south-east of Tampa, Florida.
Winds at its centre measure 105km/h (65mph) and are heading west-northwest.
Evacuations have begun in north-western Florida, where a revived Hurricane Frances could arrive by Monday evening.
Highway washed away
Despite the damage from Frances, the cost may not be as high as that from the recent Hurricane Charley, which killed 26 people in Florida three weeks ago.
Hurricane Frances ripped roofs off buildings - including some used to shelter evacuated coastal residents - and tore trees from the ground.
The northbound section of the Interstate 95 highway was closed after parts of the road were washed away.
A man died when he crashed his car into a tree and a woman was killed by an oak tree which fell on her mobile home in the city of Gainesville, in north-central Florida, rescue personnel said.
Curfews were declared along the storm's path, in part to allow repair crews to get to work quickly, but also to deter looting.
People are being warned to stay indoors until further notice, with the authorities saying there is a danger of floods after heavy rainfall.
However, flights have resumed from Miami Airport, allowing dozens of stranded passengers to leave.
The BBC's Daniel Lak in Florida says the combined cost of the clean-up from Hurricanes Frances and Charley will be immense.
Florida Governor Jeb Bush warned people to continue behaving cautiously.
"There are still dangers on our streets where the
hurricane passed," he said. "Please be patient."
His brother, President George W Bush, has declared five Florida counties major disaster zones, enabling federal relief funds to be released.
Meanwhile, another hurricane is looming on the far horizon.
On Sunday night, Hurricane Ivan was about 1,300km (800 miles) away from Barbados, but heading towards the Caribbean Windward islands.
It was packing winds of 205km/h (125mph).
Forecasters said it was too early to tell whether it would reach the US.