[Source: Reuters]

Hurricane Milton whirled into the Atlantic Ocean after ploughing across Florida, where it had whipped up a barrage of tornadoes and caused at least five deaths.

The storm knocked out power to more than three million customers and compounded the misery wrought by an earlier deadly mega storm system, Helene.

Fortunately, it spared Tampa a direct hit.

The system tracked to the south in the final hours and made landfall late Wednesday as a category three storm in Siesta Key, about 112 kilometres south of Tampa.

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 apparently did not materialise, though the storm dumped up to 45 centimetres of rain in some parts of the area, the governor said.

The worst storm surge appeared to be in Sarasota County, where it was 2.5 to three metres — lower than in the worst place during Helene.

“We will better understand the extent of the damage as the day progresses,” DeSantis said.

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

Tom Reynolds, 90, spent the morning sweeping out four feet of mud and water and collecting chunks of aluminum siding torn off by a twister that also picked up a car and threw it across the road.

Reynolds said he planned to repair the home he built three decades ago.

“What else am I going to do?” he said.

The fabric that serves as the roof of Tropicana Field — home of the Tampa Bay Rays baseball team in St Petersburg — was ripped to shreds by fierce winds.

It was not immediately clear if there was damage inside. Multiple cranes were also toppled in the storm.

St Petersburg residents could no longer get water from their household taps because a water main break led the city to shut down service.

Mayor Ken Welch had told residents to expect long power outages and the possible shutdown of the sewer system.

During a break in the storm, Tampa police rescued 15 people from a single-story home damaged by a fallen tree, authorities 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, said McDaniel, who estimated the city received 34cm 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 in a video posted online Thursday morning.

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.

In many places along the coast, municipalities raced to collect and dispose of debris before Milton’s winds and storm surge could toss it around and compound any damage.

Officials had issued dire warnings to flee or face grim odds of survival.

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 Thursday.

The Tampa airport, which took minimal damage, was expected to reopen no later than Friday, DeSantis said.