A strengthening Hurricane Irene is heading for the Turks and Caicos Islands and the Bahamas as it churns on a path towards the US.
The storm, the first hurricane of the Atlantic season, has maximum sustained winds of 160km/h (100mph). Irene earlier swept over Puerto Rico and the Dominican Republic, bringing strong winds and heavy downpours.
Forecasters say the storm is set to intensify further, reaching the south-eastern US by the weekend.
At 12:00 GMT, Irene, currently classed as a category two hurricane, was 110km (70 miles) south-south-east of Grand Turk Island, the US National Hurricane Center (NHC) in Miami said.
The hurricane was expected to be near the Turks and Caicos Islands and the south-eastern Bahamas by Tuesday night, forecasters said.
Irene was likely to strengthen further and could become a major hurricane within the next 72 hours as it moved over warm sea waters, they added.
"We didn't anticipate it gaining this much strength this early," meteorologist Chris Landsea told the Associated Press.
Bad memories On Monday, Irene knocked out power to more than half the island of Puerto Rico and affected water supplies to more than 100,000 people.
The Governor of Puerto Rico, Luis Fortuno, said he had asked the US government to declare Puerto Rico a disaster area so it could gain access to emergency funds.
In the Dominican Republic, authorities closed schools and evacuated coastal communities ahead of the storm's arrival.
Emergency preparations were also stepped up in neighbouring Haiti by United Nations agencies operating there.
The country, which suffers from extensive deforestation and poor infrastructure, is particularly vulnerable to heavy rainfall.
Hundreds of thousands of people still live in makeshift camps after the January 2010 earthquake.
In the UK overseas territory of the Turks and Caicos Islands, people have been trying to reinforce windows and doors, as well as stocking up on supplies.
On Grand Turk, where Hurricane Ike caused devastation in September 2008, resident Peter White told AP he was taking no chances.
"We've loaded up on water and rations, and our shutters are ready to go up. Bad memories of Ike are a big reason why we get so prepared now."
Hurricane Irene is on a projected path to reach the US by the end of the week, possibly making landfall in Georgia, South Carolina or North Carolina.
http://www.bbc.co.uk/news/world-latin-america-14625665