A hurricane warning is in effect for Jamaica and a hurricane watch for Grand Cayman, Little Cayman and Cayman Brac.
Beryl is rated at a Category 5 but is forecast to start losing intensity on Tuesday, though will still be near major hurricane strength when it passes near Jamaica on Wednesday, the Cayman Islands on Thursday and Mexico's Yucatan Peninsula on Friday, according to the National Hurricane Centre.
Beryl is the earliest Category 5 storm to form in the Atlantic, fuelled by record warm waters. (AP PHOTO)
The centre warned Beryl was expected to bring life-threatening winds and storm surges to Jamaica, where officials warned residents in flood-prone areas to prepare for evacuation.
"I am encouraging all Jamaicans to take the hurricane as a serious threat," Prime Minister Andrew Holness said in a public address late on Monday. "It is, however, not a time to panic."
Beryl is the earliest Category 5 storm ever to form in the Atlantic, fuelled by record warm waters.
Early on Tuesday, the storm was located about 485km southeast of Isla Beata in the Dominican Republic.
It had top winds of 270km/h and was moving west-northwest at 35km/h.
"Beryl remains an impressive Category 5 hurricane," the National Hurricane Centre said.
A tropical storm warning was in place for the entire southern coast of Hispaniola, an island shared by Haiti and the Dominican Republic.
As the storm barrelled through the Caribbean Sea, rescue crews in the southeast Caribbean fanned out across the region to determine the extent of the damage.
One person was reported killed in Grenada and another in St Vincent and the Grenadines, officials said.
The fatality in Grenada occurred after a tree fell on a house, Kerryne James, minister of climate resilience, environment and renewable energy, told The Associated Press.
One person was killed after a tree fell on a house in the hurricane-force winds. (AP PHOTO)
She said the nearby islands of Carriacou and Petit Martinique sustained the greatest damage, with water, food and baby formula a priority.
"There is no communication whatsoever," she said. "The prime minister is doing his best to get people over there to render assistance."
An emergency team was expected to travel to Carriacou on Tuesday morning.
"The situation requires our immediate attention, and all efforts must be made to support our sister islands," said Grenadian Prime Minister Dickon Mitchell.
Meanwhile, Ralph Gonsalves, prime minister of St Vincent and the Grenadines, promised to rebuild the archipelago in a statement.
He noted that 90 per cent of homes on Union Island were destroyed, and "similar levels of devastation" were expected on the islands of Myreau and Canouan.
The last strong hurricane to hit the southeast Caribbean was Hurricane Ivan 20 years ago, which killed dozens of people in Grenada.
Beryl has broken several records, including marking the farthest east that a hurricane has formed in the tropical Atlantic in June, according to Philip Klotzbach, Colorado State University hurricane researcher.
The National Oceanic and Atmospheric Administration predicted the 2024 hurricane season would be well above average, with between 17 and 25 named storms.
