Islands in the eastern Caribbean were ready for Hurricane Dean, as it approached on Thursday with 80 mph (130 kph) winds and hotels in Dominica and Martinique prepared to evacuate tourists from seaside rooms.
"We have an intensifying hurricane," said Richard Pasch, a hurricane specialist at the National Hurricane Center in Miami.
Forecasters said it was too early to say which island would catch the brunt of the storm early Friday as it passes from the Atlantic over the Lesser Antilles and into the Caribbean.
Once over the warm waters of the Caribbean, it is expected to gain strength and take a bead on Jamaica and the southern coasts of the Dominican Republic and the impoverished country of Haiti.
About 18 guests at the Jungle Bay Resort & Spa, on Dominica's Atlantic coast, will be evacuated from their cottages to spend Thursday night in a reinforced steel-and-concrete shelter, hotel spokeswoman Laura Ell said.
"Everyone's very calm but taking it seriously," she said. "Many of our guests are from Florida and used to these kinds of things."
The islands of Dominica and St. Lucia issued hurricane warnings.
"We should prepare for a worst case scenario," Cecil Shillingford, Dominica's disaster preparedness coordinator, said on state-owned DBS radio.
Yves Noel, working the front desk at the Sofitel Bakoua in Martinique, said the hotel was keeping some garden rooms available in case seafront rooms are threatened by high surf.
The hotel had about 160 guests - mostly from Europe, the United States and the Caribbean - and had seen only one or two cancellations of reservations, despite the approach of the Category 1 hurricane.
It would become a Category 2 hurricane when winds 95 mph (153 kph).
"We have to wait and see what happens," Noel said. "It's not sure if the hurricane will pass over Martinique or maybe go to the north."
A U.S. Air Force Reserve hurricane hunter aircraft will investigate Dean on Thursday afternoon, the National Hurricane Center said. It predicted waves at 2 to 4 feet above normal tide levels near the center of Dean and total possible rainfalls of 7 inches in mountainous areas.
The Hurricane Center said Dean would likely be a dangerous Category 3 hurricane by the time it reaches the central Caribbean early Sunday.
At 8 a.m. EDT, Dean was centered about 415 miles (665 kilometers) east of Barbados and about 510 miles (820 kilometers) east of Martinique, according to the Hurricane Center. It was moving west near 24 mph (39 kph), and was expected to continue the same path for the next 24 hours.
Hurricane force winds of at least 74 mph (119 kph) extended up to 25 miles (40 kilometers) from the center of the storm, and tropical storm force winds of at least 39 mph (63 kph) extended up to 70 miles (110 kilometers).
Islands near the hurricane's path could suffer wind damage and flooding from the storm, which could drop 2 to 5 inches (5 to 13 centimeters) of rain, forecasters said.
Hurricane watches were in effect for the islands of Martinique and Guadeloupe and its dependencies, Saba and St. Eustaties. Tropical storm watches have been issued for Antigua and Barbuda, Montserrat, St. Kitts and Nevis, and St. Maarten.