Jamaica’s Prime Minister Andrew Holness has toured what remains of parishes in the path of Hurricane Melissa, describing the “heartbreaking scenes”.

Aerial footage shows streets and streets of humble homes and sprawling mansions flattened along the island’s south-west coastline.

All that seems to remain are the wrecks of buildings with their roofs blown off.

Power cables are knocked down and fields are strewn with rubble.

Few buildings appear to be standing or untouched by the destructive winds that lashed with speeds of up to 300km/h when the storm made landfall on Wednesday (AEDT).

Melissa thrashed cities and towns, and isolated communities in the Caribbean, leaving dozens of people dead and a long recovery ahead.

Holness said there were images of destruction all around.

“The devastation is truly heartbreaking, yet the spirit of the people remains unbroken,” he posted to X after touring the parishes of St Elizabeth and St James.

“The strength, resilience and determination of the people of St. Elizabeth are already shining through as they focus on recovery.

“The parish of St James was also greatly affected by the passage of Hurricane Melissa.

“The impact has been significant, affecting homes, infrastructure and livelihoods across several communities.”

US forecaster AccuWeather estimated Melissa cost $US22 billion ($A33.4 billion) in damages and economic loss in Jamaica alone, and that rebuilding would take at least a decade.

Local authorities said floodwaters had washed up four bodies in the south-western agricultural hub of St Elizabeth.

The capital Kingston was spared the worst damage, with its main airport to reopen on Thursday.

Holness visited Black River Hospital, the only public hospital in St Elizabeth.

Hospital workers there said the building showed some significant damage, and staff told Holness they spent the night fearing for their own families while working by torchlight to care for patients.

“It was the most terrifying experience in all my life,” one worker said. “It is beyond imagining. At one point it was as if missiles were blowing through the glass.”

After leaving Jamaica, Hurricane Melissa thrashed Cuba’s second-biggest city, isolating hundreds of rural communities.

The storm did not directly hit Haiti, the Caribbean’s most populous nation, but it hurled days of rain over the island nation. Authorities reported at least 25 deaths, largely due to floods in Petit-Goave, a coastal town 64 kilometres west of the capital where a river burst its banks.

At least 10 children were killed and 12 people remain missing there, Haiti’s disaster management agency said.

In Haiti, where a gang conflict has displaced more than 1.3 million people, authorities said more than 1000 homes were flooded. People living in makeshift camps said the flooding made it impossible to sit or sleep, and said the government and aid groups were slow to bring supplies.

Fortune Vital, a displaced man in Les Cayes, said he was separated from his family, who already lacked sufficient food.

“If the hurricane comes on top of all the problems we already have, we’ll simply die,” he said.

Melissa was a still major category-three storm when it hit Cuba overnight with winds of 190km/h, landing in Guama, a rural, mountainous area some 40 kilometres west of Santiago de Cuba, the island’s second-most populous city.

At least 241 communities remained isolated and without communications on Wednesday following the storm’s passage across Santiago province, according to preliminary media reports, affecting as many as 140,000 residents.

Across eastern Cuba, authorities evacuated about 735,000 people as the storm approached. Most remained in emergency centres.

No deaths were reported on Wednesday but President Miguel Diaz-Canel said the island had suffered extensive damage and warned of vigilance as rains continue to lash the region.

Meteorologists at AccuWeather said Melissa was the third-most intense hurricane seen in the Caribbean, after Wilma in 2005 and Gilbert in 1988 – the last major storm to directly hit Jamaica.

But scientists say hurricanes are intensifying faster with greater frequency as a result of warming ocean waters caused by greenhouse gas emissions. Many Caribbean leaders have called on wealthy, heavy-polluting nations to provide reparations in the form of aid or debt relief to tropical island countries.

-with AAP