Governments in the Eastern Caribbean began preparing on Friday for the arrival of Hurricane Beryl, a Category 1 storm with maximum sustained winds of 130 km/h (80 mph).
Authorities in Barbados issued a hurricane watch for Dominica, which was devastated last September by Hurricane Maria, while the French government issued a tropical storm watch for Martinique, Guadeloupe, St. Martin, and St. Barthelemy.
The storm comes with Carnival in full swing in St. Lucia and St. Vincent and the Grenadines and preparations for the annual celebration well under way in Barbados.
St. Lucia's prime minister, Allen Chastanet, told EFE from Jamaica, where he is attending a conference of regional leaders, that he was in touch with his Cabinet about preparations for Beryl.
In Puerto Rico, Gov. Ricky Rossello declared a state of emergency and urged residents not to underestimate the threat.
He said that public schools would be closed on Monday and announced the opening of more than 400 shelters to accommodate people living in homes still awaiting roof repairs from the damage done last year by Hurricane Maria.
The 2017 storm and its aftermath, which saw a majority of the US commonwealth's people spend months without power and water, have been blamed for more than 4,000 deaths in Puerto Rico.
As of 2100 GMT Friday, Beryl was located roughly 1,555 km (966 mi) east-southeast of the Lesser Antilles, moving to the west at 24 km/h (15 mph), the US National Hurricane Center said in its latest advisory.
The storm may strengthen before it begins to cross the Lesser Antilles late Sunday, the NHC said.