On Wednesday, Cuba undertook a massive evacuation effort, moving hundreds of thousands of residents into shelters as a powerful hurricane loomed. A hurricane warning was issued for the provinces of Granma, Santiago de Cuba, Guantánamo, Holguín, and Las Tunas, as well as for the southeastern and central regions of the Bahamas.

The storm, named Melissa, was packing maximum sustained winds of 165 km/h and advancing north-northeast at a speed of 22 km/h, according to meteorological reports.

As of the latest advisory, Melissa was positioned 72 kilometers northwest of Guantánamo, Cuba, and about 330 kilometers south of the central Bahamas.

Authorities emphasized the urgency of storm preparations in the Bahamas, urging that these efforts “should be rushed to completion” to ensure safety.

Earlier, on Tuesday, Melissa had lashed Jamaica with fierce winds reaching up to 295 km/h before losing some intensity as it crossed over land.

It was forecast to continue weakening as it crossed Cuba and remain a strong hurricane as it moves across the southeastern or central Bahamas later on Wednesday (early Thursday AEDT).

The storm is expected to make its way late on Thursday (Friday AEDT) near or to the west of Bermuda, where a hurricane watch is in effect.

The storm was expected to generate a storm surge of up to 3.6 metres in the region and drop up to 51 centimetres of rain in parts of eastern Cuba.

The intense rain could cause life-threatening flooding with numerous landslides, US forecasters said.

The hurricane could worsen Cuba’s severe economic crisis, which already has led to prolonged power blackouts, as well as fuel and food shortages.

“There will be a lot of work to do. We know there will be a lot of damage,” Cuban President Miguel Díaz-Canel said in a televised address, adding that “no one is left behind and no resources are spared to protect the lives of the population.”

He urged the population not to underestimate the power of Melissa, “the strongest ever to hit national territory”.

Officials in Jamaica were analysing the damage.

More than half a million customers were without power late Tuesday as officials reported that most of the island had downed trees, power lines and extensive flooding.

Extensive damage was reported in parts of Clarendon in the south and in the south-western parish of St Elizabeth, which was “under water”, said Desmond McKenzie, deputy chairman of Jamaica’s Disaster Risk Management Council.

The storm damaged four hospitals and left one without power, forcing officials to evacuate 75 patients.

The government said it hopes to reopen all of Jamaica’s airports as early as Thursday to ensure quick distribution of emergency relief supplies.

The storm already was blamed for seven deaths in the Caribbean, including three in Jamaica, three in Haiti and one in the Dominican Republic, where another person remains missing.