How Hurricane Helene became the near-perfect storm, bringing widespread destruction in Southern US

A person inspects Biltmore Village with bicycle in the aftermath of Hurricane Helene on September 28, 2024 in Asheville, North Carolina. – Getty Images/AFP

HURRICANE Helene killed and destroyed far and wide – from Tampa to Atlanta to Asheville, North Carolina in the United States, its high winds, heavy rains and sheer size created a perfect mix for devastation.

The storm made landfall late Thursday (Sept 26) along a largely undeveloped expanse of pine trees and salt marshes on Florida's Big Bend coast, but it immediately displayed its far-reaching power several hundred miles away. As of Sunday morning, at least 64 people were confirmed killed.

Tampa Bay was inundated with a massive storm surge that sent water up to people's attics. Atlanta got more than 11 inches of rain, more than any 48-hour period in recorded history. So many trees were toppled in South Carolina that at one point more than 40% of the state lost electricity. In North Carolina, dams were in jeopardy of failing and entire communities are cut off by floods. Floodwaters submerged a hospital in Tennessee so quickly that more than 50 patients had to be rescued from the roof via helicopter.

How did a single storm unleash destruction so far away?

Dan Brown, a specialist at the National Hurricane Center near Miami, said Helene had all the attributes that make a storm widely destructive.

It was large, about 560km wide. It was strong, with winds reaching 225kmh when it made landfall late Thursday, creating widespread storm surge. It carried heavy rains. And it was fast, speeding north at up to 39kmh offshore and 48kmh inland.

He compared the geographic scale of Helene's destruction to 1972's Hurricane Agnes, 1989's Hurricane Hugo and 2004's Hurricane Ivan.

"Systems that get very powerful, large and fast moving unfortunately do bring the potential for impact and damage well inland," Brown said Saturday.

Here is a look at the many deadly tentacles of Helene.

Helene's devastation began Thursday, hours before it made landfall, as it swept through the Gulf of Mexico. Its then-193kmh winds created storm surge that pushed 2m-4.5m of water into island and coastal neighbourhoods all along Florida's west coast.

Nine people who drowned were residents who stayed behind after their Tampa Bay area neighbourhoods were ordered evacuated.

Pinellas County Sheriff Bob Gualtieri expressed his frustration – issuing evacuation orders isn't a decision that's made lightly, he said. Many who ignored officials then called for help as some sought refuge in their attics from the rising waters. Deputies tried to help, using boats and high-profile vehicles, but they couldn't reach many neighbourhoods.

"We made our case, we told people what they needed to do and they chose otherwise," Gualtieri said at a Friday press conference.

Late Thursday, Helene's eye slammed into the northwest Florida coast in the Big Bend area, the spot where the Panhandle makes its westward jut from the peninsula – Hurricanes Idalia and Debby had previously hit the area within the last 13 months.

Susan Sauls Hartway had evacuated her seaside home – it was gone and when she returned Friday.

"I knew it would be bad, but I had no idea it was going to be this bad," Hartway said. "This is unbelievable."

After making landfall, Helene sped into Georgia. Among more than 20 dead were a 27-year-old mother and her one-month old twins died Friday when trees fell on their house in Thomson, just west of Augusta. An 89-year-old woman was killed when trees fell on her house nearby.

Rhonda Bell and her husband were spending a sleepless night in the downstairs bedroom of their century-old home just outside Valdosta, where Helene's center passed shortly after midnight.

The winds broke off limbs, tore away neighbours' roof shingles and knocked down fence panels in the neighbourhood with train tracks along one edge. Then a towering oak tree crashed through the roof of an upstairs bedroom.

"I just felt the whole house shake," Bell said. "Thank God we're both alive to tell about it."

Atlanta was hit with 28cm of rain, the heaviest 48-hour downfall since the city began keeping records in 1878. Streets flooded, submerging cars. Firefighters rescued at least 20 people.

Helene's heavy rains in the state's western mountains caused massive flooding and mudslides in the Asheville region, cutting off most communication and making the roads impassable.

Video posted online shows large portions of the city underwater.

More than 1,610km away in Texas, Jessica Drye Turner begged on Facebook on Friday for someone to rescue her family members stranded on their Asheville rooftop.

But in a follow-up message Saturday, Turner said the roof had collapsed before help arrived and her parents, both in their 70s, and her 6-year-old nephew had drowned.

"I cannot convey in words the sorrow, heartbreak and devastation my sisters and I are going through," she wrote.

Jeff Muenstermann and his wife, Lisa, friends of Turner's, told The Associated Press on Saturday they had spoken to Turner after she posted the initial plea for help. At her request, they messaged members of The Village Church in Flower Mound, Texas, where they all attend, to pray for the family's safety back in North Carolina.

"I just thought they were going to be rescued," Jeff Muenstermann said. "I asked everybody to pray and they did. And then a couple hours later, her husband called me, completely distraught and said... we lost them. They all drowned."

The storm was especially deadly in South Carolina. The biggest impact appears to be falling trees. The storm also produced tornadoes in the state.

In Saluda County, two firefighters were killed when a tree fell on their truck while they were answering a call. In Greenville County, four people were killed by falling trees. Four people were also killed in Aiken County by trees falling on homes, including a 78-year-old husband and his 74-year-old wife.

Helene's heavy rains caused the state's eastern rivers to overflow their banks and threatened to break dams, endangering those living nearby and forcing them to flee.

Patients and others at a hospital near the North Carolina border had to be evacuated to the roof Friday when torrents from the overflowing Nolichucky River rushed into the building.

Unicoi County Hospital tried to evacuate 11 patients and dozens of others, but the water was too treacherous for boats sent by the Tennessee Emergency Management Agency to navigate.

Helicopters were flown in to help rescue them. Eventually, everyone was evacuated. – AP