This story was updated at 12:14 p.m.
Take it from the hurricane historian: There has never been a tropical cyclone quite like Irma.
“You’ve had storms this strong,” said Phil Klotzbach, a meteorologist at Colorado State University who specializes in the history of Atlantic tropical cyclones. “But the thing that sets [Irma] apart is she stayed strong for a really long time—and she’s still incredibly strong.”
Klotzbach said two things stood out to him about Irma as historically notable: its longevity and its point of origin.
As of Saturday evening, Irma has been a hurricane for 10 days, becoming the longest-lived Atlantic hurricane since Ike in 2008. It has stayed remarkably powerful over that time: When it makes landfall on Sunday, it will likely rank among the 10 lowest-pressure cyclones ever to encounter the continental United States.
But Irma had a strange origin: It became a category-five storm in a part of the world that usually does not produce huge hurricanes. When major hurricanes have struck the continental United States in the past, they have always incubated in the much warmer waters of the Gulf of Mexico or the Caribbean. That’s where Katrina grew in 2005, for instance.
Irma, on the other hand, expanded to its massive size in the tropical Atlantic, east of the Caribbean and the Gulf of Mexico. “To get something east of the islands—at least from the historical record, it hasn’t happened before,” said Klotzbach. “When people in the [Leeward] Islands were saying, ‘We’ve never seen a storm this strong,’ that’s true. They haven’t.”
Now that record-breaking cyclone comes in for its horrific finale. On Sunday morning, Irma made landfall in Florida as a category-four hurricane. It is the most ferocious storm seen in the Sunshine State since Hurricane Andrew cut east-to-west across the peninsula a quarter-century ago.
The storm’s strength has fluctuated over the past 24 hours, but officials warned that it remains extremely dangerous. On Sunday, it weakened to a category-three storm before intensifying again as it approached the Florida Keys. Forecasters expect the storm to “restrengthen a little more” over the coming hours.
The National Weather Service warned that Irma would remain an “extremely dangerous” major hurricane and bring “life-threatening wind and storm surge.” The agency has brought nearly the entire coastline of Florida—including Jacksonville, Daytona Beach, Miami, Tampa Bay, and the beaches south of Tallahassee—into its hurricane warning.
Officials described the storm as a threat to life and property with little modern precedent. “It’s not clear that this is a survivable situation for anybody who’s still there in the Keys,” said Edward Rappaport, the acting director of the National Hurricane Center, on Saturday.
“The storm is here,” said Rick Scott, the governor of Florida, in a press conference on Saturday, as tropical-storm-force winds began to batter Miami. He spoke of 15-foot storm surge, enough to submerge a one-story house. “Do not think the storm is over when the wind slows down,” he said. “The storm surge will rush in and it could kill you.”
“This is a storm of absolutely historic destructive potential. I ask everyone in the storm’s path to be vigilant and to heed all recommendations from government officials and law enforcement,” said President Donald Trump on Saturday.
“Irma has me sick to my stomach,” said Eric Blake, a scientist with the National Hurricane Center, on his personal Twitter account on Thursday evening. “This hurricane is as serious as any I have seen. No hype, just the hard facts. Take every lifesaving precaution you can.”
“I have little doubt Irma will go down as one of the most infamous in Atlantic hurricane history,” he added.
As of Saturday evening, Irma’s death toll stands at 25. The storm leaves a path of devastation across the Caribbean. On Saturday, it slammed into Cuba, becoming the first category-five hurricane to strike the island’s north end since the 1920s. The Cuban government reported 23-foot waves and sustained winds above 120 miles per hour.
In the final days of last week, the storm wrecked havoc across a series of small islands. Some of the first reports were received from the British and American Virgin islands on Saturday, after the storm made landfall on Wednesday. Videos showed devastated houses and vast expanses of flattened forest.
The storm also struck St. Martin, a tiny island of 74,000 people, popular with European tourists. Daniel Gibbs, the president of the French territory of the island of Saint Martin, estimated that 95 percent of his country had been obliterated.
“There are shipwrecks everywhere, destroyed houses everywhere, torn-off roofs everywhere,” he told Radio Caraïbes International, as translated by The New York Times. “It’s just unbelievable. It’s indescribable.”
Witnesses described similar scenes on the island’s Dutch half. “It’s like someone with a lawn mower from the sky has gone over the island,” said Mairlou Rohan, a European tourist visiting Sint Maarten, part of the Netherlands.
Officials also described outright devastation on the tiny island of Barbuda, which the storm directly hit earlier in the week. The prime minister of Antigua and Barbuda said the vast majority of that island’s housing had been destroyed. “Barbuda right now is literally a rubble,” he said. Some of the first overhead footage showed the island to be almost completely defoliated.
And though Puerto Rico was spared a direct encounter with Irma’s massive center, about 60 percent of its households were left without power on Friday. 50,000 people are without water on the island, according to the government.
The storm turned northward overnight, passing over the Straits of Florida and into the Florida Keys. After tearing through the keys, it will make landfall near Cape Coral and skirt “near or over” the Florida peninsula.
By Sunday morning, hurricane conditions set in across much of South Florida. “People in Southwest Florida need to realize this is not a Hurricane Charlie,” said Klotzbach. Hurricane Charlie made landfall as a category-four storm in 2004, killing 15 people and causing $16 billion in damages. “Charlie was bad but it was small. The winds are going to be similar, but they’ll be over a much wider area. And there will be a lot more rain, a lot more storm surge,” he said.
If Irma’s path ticks a bit further to the west, then the aggravated storm-surge effects in Tampa Bay could be catastrophic. In 2010, Tampa officials and FEMA practiced preparation for “Hurricane Phoenix,” a fictitious category-five storm that would directly strike the city. In the scenario, a tropical cyclone approached the city from the south, trapping water in Tampa Bay and deluging the region with up to 30 feet of storm surge.
For context, a maximum of eight feet of storm surge was observed during Hurricane Sandy’s catastrophic flooding of Brooklyn and lower Manhattan.
And as Eric Holthaus writes at Rolling Stone, research from the past few years has suggested that the storm-surge estimates used in the “Hurricane Phoenix” exercise were perhaps six feet too conservative.
No matter how it makes landfall, Irma’s effects will be felt across the state. As of Saturday evening, the National Weather Service said tropical-storm force windswere all but assured for most of Florida and southern Georgia. Dangerous and sustained hurricane-force winds, defined as any sustained blast faster than 75 miles per hour, were virtually certain for the state’s west coast.
Floridians fled in Irma’s path. More than 7 million people were asked by authorities to leave their homes, the largest evacuation in state history. Yet there are some signs that evacuation orders will be ignored—or simply haven’t reached some Floridians yet. The Miami Herald has found mobile-home parks where half of the residents are planning on riding out the storm. Thousands of people are also too poor to be able to afford the high gas costs of evacuating.
The storm’s last-minute westward shift also confounded preparation efforts. Irma was due to pass near Naples, which has not been directly hit by a major hurricane since it was a small town in 1921. A research model estimated it could receive more than 10 feet of storm surge. USA Today reports that it remains unclear whether some of Naples’ official shelters could withstand category-four winds.
Some Miami residents who had fled to the state’s west coast now wound up racing to return home, according to reports from Chris Hayes, an MSNBC anchor.
No matter what future devastation Irma may cause, the global hurricane records Irma has broken are already remarkable. It is the first storm ever observed, in any ocean, to sustain winds of 185 miles per hour for longer than 24 hours. (They whipped around its eye wall at that speed for 37 straight hours.) And Irma helped make Thursday the most energetic day for hurricanes on record in the Atlantic. Two other cyclones, Jose and Katia, are also churning through the Atlantic basin.
Irma’s effects can already be felt far from Florida. Hotels in Atlanta were sold out of space. And a team of meteorologists—including experts from Florida and the continental United States, and two from Hawaii—have flown into the Washington, D.C., area to staff an emergency backup National Hurricane Center. If the proper center in Miami loses contact with the world during the storm, an emergency meteorology team in College Park, Maryland, will leap into action—forecasting a storm that has marooned their colleagues to the south.