Hurricane Milton has moved into the Atlantic Ocean after ploughing across Florida, where it knocked out power to more than three million customers and whipped up a barrage of tornadoes.

The storm caused at least six deaths and compounded the misery wrought by Helene last month while sparing Tampa a direct hit.

The system tracked to the south in the final hours and made landfall late on Wednesday as a Category 3 storm in Siesta Key, about 70 miles south of Tampa.

Hurricane Milton Weather
Hangars at Albert Whitted Airport were damaged by winds from Hurricane Milton (Mike Carlson/AP)

Damage was widespread and water levels may continue to rise for days, but governor Ron DeSantis said it was not “the worst-case scenario”.

The deadly storm surge feared for Tampa never materialised, though the storm dumped up to 18in of rain in some areas, he said.

The worst storm surge appeared to be in Sarasota County, where it was 8ft to 10ft — lower than in the worst place during Helene.

“We will better understand the extent of the damage as the day progresses,” Mr DeSantis said. “We’ve got more to do, but we will absolutely get through this.”

As dawn broke on Thursday, storm surge warnings were still posted for much of the east-central Florida coast and north into Georgia.

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People are rescued from an apartment complex in Clearwater (Mike Stewart/AP)

Tropical storm warnings were in place along the coast into South Carolina.

Officials in the hard-hit Florida counties of Hillsborough, Pinellas, Sarasota and Lee urged people to stay home, warning of downed power lines, trees in roads, blocked bridges and flooding.

“We’ll let you know when it’s safe to come out,” Sheriff Chad Chronister of Hillsborough County, home to Tampa, said.

Just inland from Tampa, the flooding in Plant City was “absolutely staggering”, according to city manager Bill McDaniel. Emergency crews rescued 35 people overnight, added Mr McDaniel, who estimated the city had 13.5in of rain.

“We have flooding in places and to levels that I’ve never seen, and I’ve lived in this community for my entire life,” he said on Thursday morning.

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A house lies toppled off its stilts in Bradenton Beach on Anna Maria Island (Rebecca Blackwell/AP)

The tiny barrier island of Matlacha, just off Fort Myers, was hit by both a tornado and a surge, with many of the colourful buildings in the fishing and tourist village sustaining serious damage.

In contrast, city workers on Anna Maria Island were grateful not to be wading through floodwaters as they picked up debris on Thursday morning, two weeks after Helene battered buildings and blew in piles of sand up to 6ft high.

Those piles may have helped shield homes from further damage, said Jeremi Roberts of the State Emergency Response Team. “I’m shocked it’s not more,” city worker Kati Sands said as she cleared the streets of siding and broken lights. “We lost so much with Helene, there wasn’t much left.”

The storm knocked out power across a large section of Florida, with more than 3.4 million homes and businesses without electricity, according to poweroutage.us.

The fabric roof of Tropicana Field — home of the Tampa Bay Rays baseball team in St Petersburg — was ripped to shreds by fierce winds. Debris littered the field, but no injuries were reported.

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The roof of the Tropicana Field the morning after Hurricane Milton hit the region (Julio Cortez/AP)

St Petersburg residents could no longer get water from their household taps because a water main break shut down service. Mayor Ken Welch had told residents to expect long power outages and the possible shutdown of the sewer system.

The mayor of St Petersburg warned residents that cranes at several construction projects across the city might fall and one came crashing down at the storm’s peak on Wednesday night.

No one was injured when the crane working on a 46-storey condominium and office building — which will be the tallest residential tower on Florida’s Gulf coast — crashed into a nearby building where the Tampa Bay Times is located.

But the twisted metal gouged a hole where part of it came to rest in the brick and concrete on one corner of the building. Wires dangled down and bits of office items were strewn about.

Another part of the crane blocked the street below.

Hurricane Milton Weather
A high rise construction crane broke apart in St Petersburg (Mike Carlson/AP)

No one was working in the newspaper office at the time of the collapse. City officials cordoned off several blocks until they can assess the damage and begin working to remove the toppled and twisted crane.

At least 340 individuals and 49 pets have been rescued in ongoing search-and-rescue operations, Mr DeSantis said on Thursday afternoon.

“We are laser-focused on search-and-rescue operations today,” said Colonel Mark Thieme, executive director of the Florida State Guard.

Among the scores of tornadoes, one touched down in the lightly populated Everglades and crossed Interstate 75. Another hit Fort Myers, snapping tree limbs and tearing a filling station’s canopy to shreds.

Spanish Lakes Country Club near Fort Pierce, on Florida’s Atlantic Coast, was hit particularly hard, with homes destroyed and several people killed in tornadoes, St Lucie County Sheriff’s Office said.

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Small boats rest on a pier in Fort Myers (Marta Lavandier/AP)

Before the hurricane arrived, about 125 homes were destroyed, many of them mobile homes in communities for senior citizens, said Kevin Guthrie, director of the Florida Division of Emergency Management.

About 90 minutes after making landfall, Milton was downgraded to a Category 2 storm. By early Thursday, it was a Category 1 storm with maximum sustained winds of about 85mph and it left the state near Cape Canaveral.

The storm slammed into a region still reeling two weeks after Hurricane Helene flooded streets and homes in western Florida and left at least 230 people dead across the South.

About 80,000 people spent the night in shelters and thousands of others fled after authorities issued mandatory evacuation orders across 15 Florida counties with a total population of about 7.2 million people.

In Orlando, Walt Disney World, Universal Orlando and Sea World remained closed on Thursday. Tampa airport, which suffered minimal damage, was expected to reopen no later than Friday, Mr DeSantis said.