A hurricane has killed at least 10 people in Cuba and driven hundreds of thousands from their homes.
More than half-a-million people across Cuba have fled their homes.
Hurricane Dennis made landfall in the south-east of the country on Friday, bringing torrential rains and winds of up to 240km/h (150mph).
The storm is expected to pass east of the capital, Havana, travelling into the Gulf of Mexico before hitting southern Florida at the weekend.
Earlier it killed at least 10 in Haiti and caused heavy flooding in Jamaica.
Hurricane Dennis has "arrived, with all its diabolical force", Cuban President Fidel Castro said.
He added that eight people had died in Granma province and two in Santiago.
The storm also damaged buildings and knocked out power. About 600,000 people have fled their homes.
Cuban Meteorological Institute chief Jose Rubiera said the storm made landfall at 1300 (1700 GMT) near the central province of Cienfuegos.
At the US navy base at Guantanamo Bay, on the southern tip of Cuba, a guard tower was torn down by the fierce winds.
The storm later weakened from a category four hurricane to a category two, but it is expected to gain strength again once it reaches the Gulf of Mexico.
At 2300 (0300 GMT), the storm was 30km (20 miles) east of Havana and about 180km (110 miles) south of Key West in Florida.
The hurricane is expected to dump up to 38cm of rain on eastern Cuba, according to the US National Hurricane Center (NHC) in Miami.
Dennis, the Atlantic's first hurricane this year, is likely to rip through the Gulf of Mexico later, where oil companies have begun evacuating rigs.
A state of emergency has been declared in Florida, and tourists in the Florida Keys have been ordered to leave in anticipation of the storm's arrival.
The hurricane is the strongest to form in the Atlantic this early in the season since records began in 1851, the centre said.
Earlier, residential areas along the south coast of Jamaica were evacuated but the authorities complained that some people were refusing to leave their homes. Airports and supermarkets were closed.
Thunderstorms thrashed the Dominican Republic and southern Haiti on Thursday.
Parts of Jamaica were flooded by heavy rains
Haiti, large areas of which have been deforested, is highly vulnerable to flooding in such circumstances.
At least four people were feared dead when a bridge collapsed under pressure from a swollen river, and another died when a tree fell on a house.
Rivers burst their banks, flooding homes with 1m of water, and roofs were torn off buildings.
Oil prices surged due to the threat to oil production in the Gulf of Mexico.
Fears of another season of heavy storms pushed the price of US light sweet crude to a record $61.63 a barrel on Thursday.