Hurricane Ernesto is moving towards the Caribbean island of Bermuda, passing Puerto Rico, where more than half of the homes and businesses are without power.
Luma Energy, Puerto Rico’s main electricity supplier, said some 998,000 customers were without power as of 03:05 EDT (07:05 GMT), according to the BBC’s US partner CBS News.
Ernesto, which developed into a hurricane on Wednesday, continues to strengthen to 85mph (140km/h) ahead of its landfall in Bermuda on Friday.
Forecasters have predicted that it will become a major cyclone in the next 48 hours.
Forecasters have previously warned of the role of climate change in making such storms more intense.
Ernesto crossed Puerto Rico overnight, and the US National Hurricane Center (NHC) said up to 10in (25cm) of rain could fall in some places.
Luma president and CEO Juan Saga said more than 1,500 employees were working in the field to “re-establish service” and get power back on.
“We have to evaluate what needs to be done to solve it,” he told Reuters news agency.
Puerto Rico’s power grid has been destroyed by hurricanes before. In 2022, when Hurricane Fiona hit the island, nearly 80% of homes and businesses were cut off for nearly a month.
Ernesto is the fifth Atlantic storm of the season.
Hurricane Beryl It was the first Category 5 storm on record in the Atlantic when it hit the Caribbean and Texas Gulf Coast last month, killing dozens and leaving millions without power.
Earlier this year, the US weather agency Nova warned that the North Atlantic could receive seven major hurricanes – category three or more this year, which is twice the usual number.
Although there is no evidence that climate change is creating more hurricanes, it is making more powerful hurricanes more frequent and bringing more rainfall.
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