They thought they were prepared for Milton. Then the tornadoes came.

They weren’t expecting a tornado.

The couple raced into their bedroom closet, and Ostrander braced its door with his back. That’s when Gaza heard a sound that ruptured her eardrums.

They had chosen one of the few corners of the house that would survive.

“The minute we closed the closet door, the explosion happened,” Gaza said.

Even before Milton slammed into Florida’s Gulf Coast, a swarm of deadly tornadoes touched down on the other side of the state, ripping a gash through residential neighborhoods and retirement communities. At least six people were killed, county officials said, and search crews had rescued 25 people from homes and buildings that received significant damage. Search-and-rescue efforts are ongoing.

The barrage of late-afternoon twisters turned out to be among the most shocking and destructive elements of a storm that left more than 2.9 million utility customers without power, deluged a swath of Florida with record rain, and sent storm surges hurtling into neighborhoods near where Milton made landfall south of Sarasota.

Here in the Fort Pierce area, about 150 miles to the east, the tornadoes upended boats and mobile homes, tore off roofs and knocked down power poles. Though meteorologists had predicted some tornadoes, a common hazard for hurricanes to spin up, they said the scale and intensity of the ones that hit the Atlantic coast were more akin to the powerful twisters that carve paths of destruction across the Midwest and South.

“It’s awful throughout this entire community,” said Leo Vollbracht, the pastor at the Lakewood Park Church, its windows now shattered and half the roof torn off. “Our sanctuary is destroyed.”

The most severe impacts of the tornadoes were in Spanish Lakes Country Club Village, a retirement community in Lakewood Park that police had blocked off by Thursday afternoon. There, two entire blocks of manufactured housing — more commonly known as mobile homes — were destroyed, said Bob Heslop, president of the community’s homeowners association.

Heslop said he knew there was a risk of tornadoes as Milton approached Florida and was watching TV as they began tearing through nearby parts of St. Lucie County. There had been no hurricane evacuation order here, given the expectation that the storm wouldn’t be that bad on this side of Florida, he said. While there had been plenty of tornadoes in the area during past hurricanes and thunderstorms, so far, they had managed to avoid the Spanish Lakes community.

“You get to thinking that it’s like being struck by lightning or winning the lottery,” Heslop said. “It always happens to somebody else.”

But then he heard the roar of what sounded like a train. Huddled in his living room with his wife, Carol, and several neighbors, they heard debris hitting the roof as well as a crash outside as a tree snapped and fell on his car. In what seemed like less than a minute, it was over.

Soon sheriff’s deputies were knocking on the door, looking for anyone injured or killed. They took over the community’s clubhouse and turned it into a triage center where they assessed victims, Heslop said. The destroyed blocks of mobile homes were on streets known as Montoya and Rio de Palmas that run along the western edge of the community.

While a couple hundred of the community’s manufactured homes were what are known as concrete block on slab foundations — preventing tornadoes from easily tossing them into the air — the other 1,000 or so homes were not affixed to foundations and were more vulnerable, Heslop said.

Residents struggled to contact their family members Thursday without power, internet, little cellphone service and the police cordon outside the community.

They were left staggered by the scenes of the destruction inside.

“If you saw it, you wouldn’t believe it,” said Ron Perella, 80, a retired general contractor who has lived in the community for a decade. Of the more than 1,000 homes and trailers, he estimated half suffered damage.

“You drive down street after street, there’s nothing there,” he said. “A lot of our close friends, their houses are gone. I don’t mean there’s part of it there. Some of them are off the foundations and you don’t even know where they’re at. You see them up in the trees, but you don’t know one house from the other.”

Police and emergency personnel went house to house Thursday checking on residents.

“After they knew you were okay, they tied a little ribbon on your mailbox or your lamppost or something,” said Ron Perella’s wife, Carol.

They community has a wide range of activities for seniors, a golf course, two swimming pools, pickleball, tennis, bocce ball, shuffleboard and dances. They had been planning to have a big karaoke party Friday night.After the tornado, the clubhouse has been handing out water, ice and MREs, residents said.

In the nearby Holiday Pines neighborhood of Lakewood Park, a tight-knit community of teachers and pastors, firefighters and engineers, residents spent Wednesday girding themselves for possible flooding and strong winds, stockpiling water and other supplies as well as installing their hurricane shutters. They had been hit before by Hurricanes Frances and Jeanne, which struck within three weeks in 2004, and knew to take precautions.

That afternoon, their phones began buzzing with tornado warnings.

Crystal Hendley, a 38-year-old senior lifestyle counselor, had heard about the tornadoes from another friend and was rushing home from work. Rain was pelting down and Holiday Pines was flooding, so she left her Lexus in the Lakewood Park Church parking lot. It would be crushed by a tree.

“I was panicking,” Hendley said.

Her husband, Jason Hendley, a 46-year-old senior pastor in West Palm Beach, picked her up and they made it home, huddled in a closet when the tornado roared through from the south.

“It was like a freight train coming,” Crystal Hendley said.

A few doors away, Susan Smith, 75, and her son Andrew were sitting down at the kitchen table to play a game of Rummikub. She had lived through a Florida tornado in 1993. She knew the sound of one when she heard it. She jumped into her son’s arms.

“I held on to him for dear life,” said Smith, who has lived in the home for 21 years. “I thought it was the end, if you want to know the truth.”

The tornado ripped off solar panels from a house a couple hundred yards away and pinwheeled them into the windshield of her son’s truck. The metal enclosure over her backyard swimming pool was ripped off. The oak in her front yard toppled.

Along her road, Paleo Pines Circle, the tornado tumbled an Alpha Wolf mobile home onto one front yard, and a detailing company van onto another. Power lines slumped in the road.

Tornadoes are a common hurricane hazard, particularly as the storms move over land. At the edges of hurricanes, differences in wind speeds at varying levels of the atmosphere cause a rotating motion to develop, like a spinning pinwheel. Then strong updrafts within thunderstorm clouds can force that rotation to tip sideways, making winds spin like a frisbee instead and forming tornadoes.

But meteorologists said the tornadoes spawned by Milton were unusually intense, largely because of the time of day the storm’s outer bands were passing over Florida. They hit during the afternoon hours, when temperatures and atmospheric instability are highest — providing the main ingredients necessary for such strong tornadoes.

Copious humidity from unusually hot Gulf of Mexico waters probably also helped make the tornadoes especially powerful, said Kristopher Bedka, a severe storm researcher at NASA’s Langley Research Center.

On Thursday morning, in Holiday Pines, the whine of chain saws roared in the neighborhood as residents cut up fallen trees. A convoy of National Guard Humvees stopped in front of Gaza and Ostrander’s home, the one damaged worst on the block, to check on their well-being.

The couple had lived in the house for nearly a decade and loved the neighborhood. As Hurricane Milton approached, they moved belongings inside. Ostrander, a civil engineer with the Fort Pierce utility authority, was planning on making something for dessert and watching a movie.

By about 3 p.m., their house lost power. They were getting tornado warnings on their phone. When it came about 4 p.m. the tornado passed through in what felt like seconds.

Ostrander stepped out of the closet. He was wearing shorts, no shirt, no shoes. He looked up.

“It was all light,” he said.

The rest of the house was destroyed. And the hurricane that everyone worried about was yet to make landfall.

Dance reported from Washington. Kasha Patel and Allyson Chiu in Washington contributed to this report.