Tropical Storm Gustav slammed Jamaica overnight with 65 mph winds. The storm’s path was expected to take it to Grand Cayman later on Friday.
Gustav could intensify into a Category 3 hurricane (winds above 111 mph) by the time it reaches western Cuba on Saturday, according to the National Hurricane Center.
On Thursday, the U.S. Department of State issued a travel warning to U.S. citizens about traveling to storm-affected areas, including Haiti, Jamaica and the Cayman Islands.
In Jamaica, both airports in Montego Bay and Kingston remained closed on Friday morning. More than 700 people were in 31 shelters along Jamaica's south coast.
Gustav knocked out electricity, flooded roads and caused storm surges and mudslides along its path as it lumbered on a west-northwest track from Kingston, the island's capital.
Cayman Airways added 12 flights between Grand Cayman and Miami on Friday, although there was not yet a mandatory evacuation policy in place for Cayman Islands visitors or residents.
Beyond Jamaica, oil companies were pulling workers off drilling rigs in the Gulf of Mexico, and both Louisiana and Mississippi declared a state of emergency as forecasters warned of a U.S. landfall early next week.
Meanwhile, Tropical Storm Hanna, which formed on Thursday northeast of Puerto Rico as the eighth named storm of the Atlantic hurricane season, is forecast to veer between the Bahamas and Bermuda over the next few days.
Gradual strengthening is forecasted, and Hanna could become a hurricane by Saturday.