Hurricane Paloma slammed into southeastern Cuba, a dangerous Category 3 storm with 200-kilometre per hour winds, after lashing the Cayman Islands, the Miami-based US National Hurricane Centre said.

More than half a million people were evacuating in central provinces and some 3000 foreign tourists were being sheltered on northern holiday islands in the central region of Ciego de Avila, the Civil Defense said.

"Major Hurricane Paloma makes landfall near Santa Cruz del Sur, Cuba," the NHC said in its 7pm bulletin.

The hardscrabble town of Santa Cruz found itself in Paloma's crosshairs 76 years after another major hurricane devastated the area, leaving more than 3000 people dead in the largest natural disaster in modern Cuban history.

Cuba's Civil Defense had issued hurricane warnings for the central and eastern provinces of Camaguey, Las Tunas, Holguin, Granma, Santiago de Cuba and Guantanamo.

Expected to wreak havoc

The hurricane was expected to wreak havoc on the cash-strapped communist-ruled island of more than 11 million people — roughly the size of Portugal (the US state of Virginia) — already devastated this season by two other monster storms.

Paloma lost some steam as it approached the Cuban mainland dropping from Category 4 to 3, in the Saffir-Simpson Scale of 5.

"Steady weakening is expected for the next day or two... especially as Paloma moves across Cuba," the NHC said.

Churning east-northeast at 17 kilometres an hour, Paloma was also forecast to decrease in forward speed as it makes its way across Cuba.

Paloma had intensified to a Category 4 storm with winds up to 215 kilometres per hour as it crossed the Caribbean, leaving devastation in its wake on the Cayman Islands, a British territory with tourism and banking interests, south of Cuba's southern coast.

Cayman also hit

Residents of Grand Cayman emerged from shelters on Saturday morning to piles of debris, flattened trees, and localised flooding.

Power to most of the island had been restored by midday, and Grand Cayman's Governor Stuart Jack reported no casualties.

But the smaller islands of Cayman Brac and Little Cayman were devastated by the strongest storm to hit the islands since 2004's Hurricane Ivan.

"Probably 90 to 95 percent of homes and buildings have been damaged" on Cayman Brac, local commissioner Ernie Scott told AFP by telephone. "Some have been totally devastated."

There were no early reports of casualties, as all tourists were evacuated and most residents were moved to shelters, Scott said.

In Cuba, "potentially catastrophic storm surge flooding of 4.5 to 6.0 metres accompanied by large and dangerous battering waves is expected near and to the east of Santa Cruz del Sur along the south coast of Cuba," the NHC said.

Most residents had evacuated Santa Cruz by midday on Saturday to avoid a potential repeat of the 9 November 1932 storm that hit near Santa Cruz with winds topping 250 kilometres per hour, inundating the area with nine-metre waves and killing 70 percent of the population.

Cuba is reeling from a devastating storm season and Paloma is the third hurricane to crash into the island in 60 days. The Atlantic hurricane season stretches from 1 June to 30 November.

The season's storms, including Hurricanes Gustav and Ike, have left hundreds dead across the Caribbean and Central America and wrought billions of dollars in damage.

Paloma was forecast to power across Cuba and into the Atlantic Ocean by Sunday morning.

It is expected to reach the central Bahamas late on Sunday or Monday.

AFP