Cuba and the Bahamas in path of Hurricane Michelle

Cuba braced itself yesterday for what may be the worst storm to hit the island in more than 50 years, amid predictions that Hurricane Michelle was to lash its shores with waves up to 25ft high.

The hurricane, which has already killed 10 people and left 26 missing in Central America, was expected to race across the tobacco-growing provinces of western Cuba before hitting the Bahamas and the American state of Florida with 135mph winds. As the fringe of the hurricane hit Cuba's southern coastline yesterday, 13ft waves pounded the shore, accompanied by heavy rain.

Jose Rubiera, the country's chief meteorologist, said the danger should not be underestimated. "It's an imminent threat, the most dangerous one we have had in the last 50 years," he said.

The island's communist authorities have gone on to full alert, ordering the evacuation of 150,000 people from rotting apartment blocks in the capital, Havana, and supervising measures to protect houses and official buildings.

Although Havana is not in the hurricane's projected pathway, neighbourhood Committees for the Defence of the Revolution told residents to tape up their windows and tie down roofs.

The precautions were taken because meteorologists have warned that only a small deviation by the hurricane to the left of its expected path could bring it on to the northern coast beside Havana.

That could result in waves of up to 25ft breaking against Havana's sea wall, sending water into residential areas.

Most incoming international flights and domestic flights were suspended. In the western province of Pinar del Rio, likely to be the hardest hit, workers rushed to harvest tobacco leaves for Cuba's Havana cigars

President Fidel Castro said the nation should remain calm. "It's not very nice to be visited by a cyclone now," he said on television on Friday night. "But no one's in a panic ... we're calm, serene and secure."

Michelle has generated far stronger winds than Hurricane Lili, which wiped out crops and left thousands homeless when it hit Cuba in 1996.

A disastrous hurricane in 1932 flattened the northern coastal town of Santa Cruz del Sur and killed more than 3,000 people. Authorities in the United States are already hunkering down in anticipation of Michelle's arrival. The National Hurricane Service in Miami said Michelle was "an extremely dangerous hurricane". Tourists and residents of mobile homes and low-lying areas were being evacuated from the Florida Keys as a hurricane watch went into effect.

Although only one main road links the islands, US1, traffic was reported to be light – probably because many Keys residents normally ignore evacuation orders. Hurricanes Andrew, which devastated southern Florida in 1992, and Hugo, which ravaged several south-east American states in 1989, were category 4 storms, the same level as Michelle.

In Central America, rescuers were struggling yesterday to reach thousands of people left homeless by floods caused by the storm. In Honduras, the authorities said the storm had killed six people, left 14 missing and forced 100,000 to flee their homes in search of higher ground.

The Bahamian government also issued a hurricane watch for its north-western and central islands, including Grand Bahama.