Forecasters on Tuesday issued a tropical storm warning for Puerto Rico and other parts of the Caribbean, saying a disturbance in the Atlantic is likely to soon strengthen into a tropical storm that might eventually reach the U.S. mainland.

The storm, which could be named Isaias if it gains force, was expected to move through the Leeward Islands on Wednesday, and near or over the Virgin Islands and Puerto Rico on Wednesday night. It would be over Hispaniola on Thursday.

The U.S. National Hurricane Center in Miami issued warnings for Puerto Rico, the British and U.S. Virgin Islands, Antigua, Barbuda, Dominica, Martinique , Montserrat, St. Kitts and Nevis, Guadeloupe, Martinique, St. Martin, St. Maarten, Saba, St. Eustatius and portions of the Dominican Republic. A tropical storm warning means that tropical storm conditions are expected somewhere within the warning area within 36 hours.

The long-term forecast showed the storm headed toward the southeastern U.S., though the Hurricane Center said, “It cannot be stressed enough that since the system is still in the formative stage, greater than average uncertainty exists regarding both the short-term and longer-term track and intensity forecasts.”

Officials in Puerto Rico said in a news conference that they were concerned about potential flooding and urged people not to lower their guard, noting that the U.S. territory is struggling with a spike in COVID-19 cases.ñ The island also is still trying to recover from 2017's devastating Hurricane Maria and a string of earthquakes earlier this year that damaged or destroyed hundreds of homes in the island's south.

“We're not facing a situation like Maria, but we have to remain wary,” said Pedro Janer, secretary of the Department of Public Safety.

Many worried about whether Puerto Rico's fragile power grid, which was destroyed by Maria, would withstand tropical storm force winds. On Tuesday, the island's power company announced that more than 250,000 customers were left without electricity when a plant was knocked offline for unknown reasons.

On Tuesday afternoon, the storm system was centered 435 miles (700 kilometers) east-southeast of the Leeward Islands. It was moving west at 23 mph (37 kph).

The maximum sustained winds were 40 mph (65 kph) with higher gusts. Forecasters said some strengthening was expected during the next 48 hours, with the system expected to become a tropical storm Tuesday night or Wednesday.

Forecasters estimated the northern Leeward Islands, British and U.S. Virgin Islands and Puerto Rico would experience 3 to 6 inches (8 to 15 cm) of rainfall with maximum amounts of 10 inches (25 cm).

By DÁNICA COTO
Associated Press

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