Florida's north-west is steeling itself against the impact of Hurricane Katrina, which killed seven as it swept across the southern coast.
Residential areas of Florida have been flooded
The hurricane is swelling as it crosses the Gulf of Mexico.
Katrina, the sixth deadly hurricane to hit Florida in a year, is moving westwards at nearly 7mph (11kph).
Forecasters said the hurricane, expected to make landfall on Monday, could hit anywhere from Florida to Louisiana.
A dozen oil platforms in the Gulf have been already been evacuated.
Forecasters have warned Katrina could reach a dangerous category four, the second highest level on the Saffir-Simpson scale.
Insurers estimated losses caused by Katrina so far will add up to between $600m (£333m) and $2bn (£1.1bn).
In southern Florida, lashed by Katrina on Thursday and Friday, some 850,000 people remain without power.
The authorities said it would take days to restore power to those affected.
Katrina crashed ashore on Thursday night in Broward County, uprooting trees and downing power lines.
Four people were killed by falling trees and two men died aboard boats in the Miami area.
Another man died when his car struck a fallen tree.
Katrina was only a category 1 hurricane when it landed, but people were stunned by her ferocity.
"It's been horrible," said Carolyne McHyman of badly-hit Hallandale Beach. "Basically all our windows are leaking. We just keep mopping up and taping the windows, mopping up and taping again."
Schools and offices remain closed although Miami's international airport has re-opened.
Glitzy parties and concerts ahead of the MTV Video Music Awards in Miami on Sunday had to be cancelled.
Florida Governor Jeb Bush said he had requested federal assistance for the afflicted areas.
"Federal resources are on-site and are ready to be deployed. These resources include water, food, ice and personnel, and expertise in search-and-rescue, should the state require them," said Trent Duffy, a spokesman for US President George W Bush.
Thirteen years ago this week, the maximum-strength Category Five Hurricane Andrew hit the same area of Florida - the most costly hurricane to hit the US.