Residents in South Florida's Palm Beach County were told to evacuate their homes by 2 p.m. (1800 GMT) Thursday, and authorities prepared to place the southeastern state on a hurricane watch.

While some forecasts have the hurricane slamming into Georgia or South Carolina over the weekend, most experts believe there is a stronger chance it will hit Florida, after churning over the Turks and Caicos and the Bahamas.

"We want everybody in the state to know there will likely be some impact from this very dangerous hurricane," said Max Mayfield, director of the Miami-based National Hurricane Center.

"If it remains a category four hurricane it certainly will cause extreme damage," he said at a news conference.

He also warned that because of the size of the storm, whose winds extend 130 kilometers (80 miles) from the center, "the hurricane will not be just a coastal event. Wherever it strikes land, those strong winds, heavy rains and some of the tornadoes will spread well inland."

At 5:00 p.m. (2100 GMT) hurricane hunter planes located Frances 1,050 kilometers (650 miles) east-southeast of the Florida coast. It packed winds of 220 kilometers (140 miles) per hour, with higher gusts.

Florida is still recovering from the death and destruction wrought earlier this month by Hurricane Charley, which hit southwestern areas.

"Wherever Frances makes landfall it will likely have impact over a much, much larger area," said Mayfield.

Stores in South Florida were doing booming business with hurricane supplies, including plywood to board up windows, bottled water and generators.

The eventual track of the hurricane will depend largely on a ridge of high pressure just north of the storm. If that system remains where it is and maintains its strength "it will be a Florida hurricane," said Mayfield.

All rights reserved. � 2005 Agence France-Presse. Sections of the information displayed on this page (dispatches, photographs, logos) are protected by intellectual property rights owned by Agence France-Presse. As a consequence, you may not copy, reproduce, modify, transmit, publish, display or in any way commercially exploit any of the content of this section without the prior written consent of Agence France-Presse.