SAN JUAN, P.R. — One of the most powerful Atlantic hurricanes ever recorded crescendoed over the Caribbean on Thursday, crumpling islands better known as beach paradises into half-habitable emergency zones and sideswiping Puerto Rico before churning north. It is expected to hit the Florida Keys and South Florida by Saturday night.
More than 60 percent of households in Puerto Rico were without power. On St. Martin, an official said 95 percent of the island was destroyed. The Haitian government called for all agencies, stores and banks to shut down as the storm hit. Prime Minister Gaston Browne of Antigua and Barbuda said that half of Barbuda had been left homeless.
Watching Hurricane Irma maraud across Barbuda and Anguilla, residents of Florida and others who found themselves on the wrong side of the forecast were hastening to get out of the way. Government officials in Florida, Georgia and South Carolina pleaded for people to evacuate vulnerable areas, triggering a scramble for the essentials — gasoline, water, sandbags — that, even for hurricane-hardened Floridians, was laced with dread and punctuated with dire warnings from every direction.
A shortage of gasoline and bottled water, always a headache in the days before hurricanes, grew more acute in the wake of Hurricane Harvey, as the production of Houston oil refineries shrank and fuel and water were diverted to Texas. Pump lines in South Florida sprawled for blocks as fleeing residents sucked up what gas they could, and some drivers chased after tankers they had spied on the roads.
Gov. Rick Scott of Florida urged extreme caution in the face of a powerful storm that could quickly change course. “Every Florida family must prepare to evacuate regardless of the coast you live on,” he said.
By the time Rosi Edreira and her husband got the order to leave their home in Cutler Bay, part of the second evacuation zone in Miami-Dade County, they had already made plans to seek shelter in Charlotte, N.C. Into the car would go photo albums, birth certificates, nearly 400 Christmas ornaments collected over a quarter-century and their two dogs, JJ and Coco Puff, and cat, Dicky.
“I did Andrew,” said Ms. Edreira, 49, recalling the massive Category 5 hurricane that ripped off her roof 25 years ago last month. “I’m not doing that again.”
By Thursday night, Irma’s 175-mile-an-hour winds and pelting rains had already serially ransacked the islands of the eastern Caribbean, leaving at least seven dead and whole communities flattened.
Not all the news was awful. Despite the loss of power to most of the island, damage and loss of life on Puerto Rico was far less than feared. Haiti and the Dominican Republic, which share the island of Hispaniola, were also spared direct hits.
But the terror of the storm left people grasping for superlatives.
“There are shipwrecks everywhere, destroyed houses everywhere, torn-off roofs everywhere,” the president of the French territorial council on St. Martin, Daniel Gibbs, told Radio Caraïbes International.
“It’s just unbelievable,” he added. “It’s indescribable.”
In Puerto Rico — among Irma’s less unfortunate casualties — the lights were out. In many places, so was running water.
Though the hurricane barely brushed the island, it managed to knock out its aging electrical system. More than a million customers were without power on Thursday, and a little more than half of the hospitals were functional. Even before a single raindrop fell, the head of the company, which is effectively bankrupt, had predicted that if the storm packed a wallop, it could take four to six months to completely re-establish service. His prediction infuriated Puerto Ricans, who see the latest development as yet another shameful indignity in the island’s yearslong economic decline.
How is it possible, they wanted to know, that a hurricane that had passed at a safe distance and hardly claimed a shingle could leave so many in the dark?
Puerto Rico’s plunge into darkness has been long coming. In July, the huge, government-owned power authority defaulted on a deal to restructure $9 billion in debt, effectively declaring bankruptcy.
It has neither modernized nor kept up with maintenance. Trees have gone untrimmed, poles unattended. (The electric company did not respond to repeated requests for comment.)
Gov. Ricardo A. Rosselló said the authorities could not estimate how long it would take to get the power back until officials were able to survey the damage.
Thursday afternoon he said service had been restored to 144,000 households — which still left nearly a million out.
Still, he said, things could have been much worse.
“We would like to start out thanking the almighty,” Mr. Rosselló said. “Our prayers were answered.”
On other islands, the reckoning was far more stark.
On St. Martin, a part-French, part-Dutch possession where at least four people died as a result of the storm, aerial footage taken by the military showed streets inundated with water and homes devastated by winds. The second wave of destruction, for businesses at least, was man-made: looters were picking through the remains, sometimes in view of police officers who stood idly by, “as if they were buying groceries,” said Maeva-Myriam Ponet, a correspondent for a television network based in Guadeloupe, another French Overseas Territory in the Caribbean.
St. Martin remained mostly isolated from the outside world on Thursday, lacking power and most cellphone service.
Ms. Ponet, who reports for the Guadeloupe 1ère network, said the residents of St. Martin felt utterly neglected. “Help will arrive tonight,” she said, “but for the moment, they don’t have anything.”
The nearby island of St. Barthélemy, another French territory, was also hard hit, as was Barbuda, where half of the island’s residents were reportedly left homeless.
The network’s correspondent in St. Barthélemy, Eric Rayapin, described a “spectacle of desolation,” with the island all but severed from the outside world. There had been little or no phone service, water or electricity since Tuesday night.
Buildings have been “ravaged,” he said, and many roads have been destroyed.
“The population here is suffering enormously,” Mr. Rayapin reported. “Some of them have lost their houses, the cars have been flipped over in the middle of the street, and all vegetation has been destroyed.”
He added: ”It’s a very hard blow.”
John McKendrick, Anguilla’s attorney general, said that the island, a British possession, had suffered “huge devastation” from the hurricane.
Most of the island’s homes had been damaged, fallen trees had blocked many roads, cellphone service was interrupted and electrical service was cut. The entire island was still without power midday Thursday, and the ports and the airport remained closed. One person in Anguilla died, Mr. Kendrick said, though he did not know the circumstances.
“It’s been bad,” Mr. McKendrick said in a telephone interview from London, where he had been traveling when the hurricane struck the island. “A lot of people are exhausted and a lot of homes are damaged.”
He said the authorities were still trying to assess the full scope of the destruction.
In Haiti, the government called for all institutions to be shut down from noon on Thursday until further notice. President Jovenel Moïse urged people to get to a safe place.
“The hurricane is not a game,” he said.
The danger was not only of drownings and injuries from the storm. Officials worried that a surge of cholera could follow, as it did last year after Hurricane Matthew devastated the country’s southwest. Government reports show that the cholera that broke out in Haiti starting in 2010 has killed 104 people to date. In an effort to avert another flare-up, Haiti’s minister of public health urged people to add bleach to their drinking and bathing water and to assemble first-aid kits at home.
Among the deepest concerns of Mr. McKendrick, the Anguilla attorney general, was the approach of Hurricane Jose, declared a Category 3 storm on Thursday, which is expected to make its way through this same part of the Caribbean on Saturday. A Hurricane Watch was in effect for Antigua and Barbuda and a Tropical Storm watch was issued for Anguilla, Montserrat, St. Kitts, Nevis, Saba and St. Eustatius.
“A 137-mile-per-hour storm is on the way,” he said. “I’m not sure how the island can respond to that.”
In Miami, Elizabeth Chifari, 66, was determined to stay home with her white alley cat, Friday, and ride out the storm.
She would have gone to stay with her son, Andrew. But he lives in Houston.
“If they lived anywhere else,” she said, “I would’ve considered it.”