(AP) -- Tropical Storm Maria swirled toward the eastern Caribbean on Friday, threatening to unleash heavy rain and wind on islands still struggling to recover from a recent hurricane.
The storm had maximum sustained winds of 45 mph (75 kph) Friday afternoon, with some slight strengthening possible, said the U.S. National Hurricane Center in Miami. It was centered about 215 miles (345 kilometers) east-southeast of the French Caribbean island of Guadeloupe and moving northwest at about 16 mph (26 kph).
Tropical force winds will start lashing the U.S. Virgin Islands on Saturday morning, where the storm is expected to dump up to 6 inches (15 centimeters) of rain, said Walter Snell with the National Weather Service office in Puerto Rico.
"Residents should be prepared for whatever the worst this storm can do," he said.
Maria is forecast to become a Category 1 hurricane late Monday and possibly a Category 2 hurricane by Tuesday, when it is expected to pass just east of the Bahamas as it continues on a northward path, the hurricane center said.
Flight cancellations were reported across the Caribbean region Friday.
The U.S. Virgin Islands government said it would close its airport Saturday and has advised an estimated 3,000 tourists currently in the territory to stay indoors.
In Puerto Rico, the government urged tourists to leave the islands of Vieques and Culebra, warning that the last ferry bound for the main island would depart early Friday night.
State Secretary Kenneth McClintock said all 9-11 remembrance acts planned for Sunday have been canceled as a result of the storm, including a Mass and a pilgrimage to the governor's mansion.
"At this moment, all Puerto Ricans should have as their priority the preparation for Tropical Storm Maria," he said.
In Antigua, the government said it would close the airport early Friday night after shutting schools that morning so they could be used as emergency shelters if needed.
Some residents stocked up on gas, food and water in case they lost power.
"I just wanted to get a few things to get us through the weekend," said Josephine Samuel, who lives in Antigua's central region. "I don't see what everyone's fussing about. It's a storm."
Meanwhile, officials in the British Virgin Islands warned they would likely turn off the water supply until the storm dissipated.
Many islands are still cleaning up the damage from Hurricane Irene, which lashed the region in late August, killing at least eight people.
A tropical storm warning was in effect for a host of islands: Antigua, Anguilla, Barbuda, Montserrat, Nevis, St. Kitts, the British Virgin Islands, the U.S. Virgin Islands, Guadeloupe, St. Maarten, Saba, St. Eustatius, St. Barthelemy, St. Martin, Martinique, Dominica, and Puerto Rico, including Vieques and Culebra.
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