Crowds of concerned residents are preparing for Storm Dorian in Puerto Rico, amid fears it could cause chaos as it heads for the Dominican Republic.
The tropical storm has already dumped immense rainfall on the Winward Islands of the eastern Caribbean.
It is set to brush past Puerto Rico's southwest cost and then to hit the eastern Dominican Republic at hurricane strength on Wednesday.
Images have shown those living in areas bracing for the storm stockpiling water and other supplies from supermarkets.
Photos from Puerto Rico showed empty supermarket shelves as people grabbed cases of bottled water, filling trolleys to the brim.
A still-uncertain long-term track showed the storm near Florida over the weekend, while the US National Hurricane Centre issued a hurricane watch for Puerto Rico and for the Dominican Republic from Isla Saona to Samana.
It also distributed tropical storm warnings for Martinique and St. Vincent and the Grenadines.
Experts at the centre said the storm has maximum sustained winds near 50 miles per hour and is forecast to strengthen during the next 48 hours before passing near or south of the US territory.
Overnight the storm knocked out power in Barbados, where crews began clearing downed trees and repairing the electrical grid early on Tuesday.
Jackie Marshall-Clarke, a spokeswoman for Barbados Light & Power, said on state-owned TV many communities in the island's northern region were without electricity.
Government officials said that by Tuesday morning, public transportation would resume and businesses would reopen.
Minister of Home Affairs Edmund Hinkson said Dorian "is said to be weakening and that is great news, but we are not out of danger yet".
