Florida authorities issued evacuation orders for nearly half a million residents, and a hurricane warning was extended from Sebastian Inlet in central Florida to Cape Romain, South Carolina. The warning means that hurricane winds or dangerously high tides are expected within 24 hours.
Residents along Georgia's coast were boarding up windows and heading inland. "We're frantically packing up our data files," said Barb Zoodsma of the coastal resources division of the state's department of natural resources, which has its headquarters in the marshes near Brunswick.
The evacuation area includes the Kennedy Space Center at Cape Canaveral, where Nasa has moved the space shuttle Atlantis from the launch pad to the safety of its hangar.
"The hurricane is getting [too] close for comfort," a Florida state meteorologist, Mike Rucker, said.
Four people died earlier this week when Bertha, the first hurricane of the season, hit Puerto Rico and the Virgin Islands.