The storm, driving sustained winds of nearly 95 kmh, was at 2100 GMT (5am Singapore time) centred near the vacation hub of Key West, or about 235 km south of mainland Florida at Fort Myers.

A state of emergency was in place in Florida in anticipation of Fay's landfall, expected 'over the southwestern coast of Florida on Tuesday,' the Miami-based National Hurricane Center said.

The storm's tail of heavy rain was still pounding Cuba, which escaped Fay's passage with little more than blown-off roofs, uprooted trees and some flooding, but no deaths.

The Dominican Republic and Haiti were not so lucky, with numerous deaths reported. The worst incident was in Haiti, where a truck carrying around 60 passengers plunged into a swollen river.

Civil protection officials said half the passengers were missing, with many feared drowned, but no firm toll was immediately available.

Four people were killed in the Dominican Republic due to the heavy rains, with thousands evacuated, media said.

One woman also reportedly died in Jamaica after her vehicle overturned in flood waters.

In Florida authorities ordered the evacuation of tourists and closed schools in the Keys. In Key West, four shelters were set up in case residents were also forced to abandon their homes. Flights were canceled.

The NHC warned people to complete 'Preparations to protect life and property.'

It said the storm was powering up to a possible category one hurricane - when winds top 120 kmh - with storm tides up to 1.5 m higher than normal.

Florida Governor Charlie Crist said the storm would likely have an impact over a broad area.

'Tornadoes are likely in some areas tonight (Monday) and tomorrow, and maybe even into the next few days,' he told a media conference.

Some 500 national guard members were deployed, with another 8,500 available if needed, Mr Crist said.

In Miami, anxious residents descended on gas stations and supermarkets to grab petrol and bottled water. Television stations broadcast warnings about the risk of power cuts.

But crude oil prices fell on Monday as Fay's path appeared likely to bypass oil and gas production facilities in the Gulf of Mexico.

Royal Dutch Shell said it had evacuated 425 staff from the Gulf of Mexico but added that no more workers would leave as Fay appeared likely to miss its energy installations.

Spain's government offered to help Dominican Republic, Haitian and Cuban authorities cope with Fay's aftermath.

After roaring through Florida, the storm is expected to continue north, albeit with less power, into Georgia state, although its path was unpredictable.

Fay is the sixth named storm of this year's Atlantic hurricane season, which runs from June 1 to November 30. -- AFP