Rising water masses caused by Hurricane Helene led to this Briana Gagnier and her family swim out of their home on Florida's Gulf Coast.

Ms. Gagnier, who lives in Holmes Beach, north of Sarasota, had stayed behind with her family to protect their one-story home. She placed sandbags at each door and placed her belongings on high furniture to keep them dry. They even used towels to prevent water from entering.

Then came a loud bang. Her garage door opened violently – and collapsed after Helene's powerful storm surge. The water quickly rose to their shoulders, forcing them to flee quickly.

“Everyone was screaming and panicking,” she told the BBC. “Whatever your worst idea of ​​this storm is, this is what we’re seeing.”

Ms. Gagnier is one of many Florida residents living along the state's Big Bend Coast who are now suffering the effects of Hurricane Helene, a strong, deadly Category 4 hurricane that made landfall Thursday evening before moving inland a tropical storm weakened.

Millions of homes across the southeastern United States were without power Friday morning, and the storm is blamed for several deaths in the region.

A storm surge of up to 6m – the size of a two-story building – was forecast in some coastal areas.

Authorities say at least one person died in Florida after a traffic sign fell on their car.

Two others died in Georgia, where the storm caused a tornado that toppled a mobile home.

Footage from the aftermath of Storm Helene shows flooded neighborhoods and submerged cars, requiring multiple rescue operations for those trapped by the storm, while locals reported widespread devastation.

In one rescue, a man and his dog were rescued by the U.S. Coast Guard after his 36-foot sailboat began taking on water.

The man, who the Coast Guard did not name, was sailing 25 miles off the coast of Sanibel Island when he was struck by the hurricane. He called Channel 16 – the marine emergency channel – to call for help.

On land, residents saw uncontrollable water pouring into homes and businesses as the hurricane approached.

ML Fergusona resident of Anna Maria Island told the BBC that the streets in the area had turned into rivers.

When she returned to her home late Thursday, she found it, too, flooded.

“Oh my God, it literally comes down to the second step,” she told the BBC in a telephone interview, before quickly hanging up and rushing to prevent more water from getting in.

After Ms. Gagnier, the Holmes Beach resident, swam out of her home, she and her family ran across the street to a neighbor's house, where they eventually rescued two elderly people whose home had burst into flames.

She said the cause was unclear but appeared to be related to a golf cart battery.

As she looked around, she said she saw couches, chairs, a bench and even a car driving by. The water was over her mailbox for part of the evening, she added.

“I just can't believe this is real. The eye of the storm didn’t even hit us directly,” Ms. Gagnier said. “This island is completely destroyed. Everywhere I look, devastation.”

In Tallahassee, Florida, some residents like Cainnon Gregg had huddled together to weather the storm. Mr. Gregg, who was staying at a friend's shelter, said he wanted to stay near the water to check on his oyster farm as soon as it was safe to do so.

He had spent the last few days protecting it by sinking it into the ocean floor. His farm was destroyed once before during Hurricane Michael — a Category Five hurricane that hit the Florida panhandle in 2018 — and he said he is determined to learn from that lesson.

“Hopefully, and nothing is certain, the farm will be nice and safe on the bottom,” he said before the storm. “But anything could happen.”