A fifth person reported killed by now-Tropical Storm Helene was trapped inside a home by a fallen tree in Charlotte, North Carolina, authorities said. A second person in the home was rescued. Other fatalities were reported in Florida and Georgia.

Hello, this is Richard Luscombe in Florida picking up our live blog coverage of Hurricane Helene’s impact on the south eastern US.

Daylight here within the last hour has given hundreds of thousands of people their first glimpse of the devastation caused by the category 4 hurricane that swept ashore shortly after 11pm local time last night.

At least five people were killed, a death toll expected to rise; more than three million people are without power; storm watches and warnings have been posted in 12 states; and a flash flood advisory is in place in Atlanta.

Ron DeSantis, Florida’s governor, is expected to give an update within the next hour. Helene, meanwhile, has been downgraded to a tropical storm, but is still dumping rain and causing havoc over a wide area.

Stick with us for the latest developments.

Shannon Ho

Flash flood emergency issued for Atlanta area

Shannon Ho

3 million without power as 'life-threatening' conditions batter south-east US

Shannon Ho

Watch footage of swamped neighbourhoods as Hurricane Helene made landfall in Florida.

Storm watches and warnings are in place in 12 states, CNN reports.

Six states have declared emergencies.

More than 1.28 million homes and businesses in Florida were without power today, Reuters reported.

Helene weakens to tropical storm as life-threatening winds and rains continue

In a 4am update, the National Hurricane Center said “Helene continues to move inland over central Georgia and is producing hurricane-force winds and heavy rainfall.”

“This is a dangerous and life-threatening situation,” the center said.

“A University of Georgia weather station in Vidalia, Georgia recently reported a wind gust of 77 mph (124 km/h). An ASOS station at The Savannah International Airport in Georgia recently reported a sustained wind of 49 mph (79 km/h) with a gust to 76 mph (122 km/h),” it added.

Joe Biden has said he is “closely tracking Hurricane Helene.”

“I urge everyone in and near the path of Helene to listen to local officials and follow evacuation warnings,” he said.

Hurricane force winds move further into Georgia

Tell us: have you been affected by Hurricane Helene?

What is a storm surge, and what is the threat from Hurricane Helene?

Hurricane Helene is the most powerful storm to hit the US mainland since Idalia, which barreled into Florida on 30 August last year at Keaton Beach.

Similar in strength, and location at landfall, to Helene, Idalia followed an almost identical path through the Gulf of Mexico on its way to becoming the third strongest cyclone to strike Florida’s Big Bend.

Such was its strength that Florida’s famous flamingos were spotted as far north as Ohio and Pennsylvania in the storm’s aftermath. Idalia was blamed for 12 fatalities in the US, and caused damage estimated at $3.6bn. Officials fear Helene’s toll could prove much worse.

These are the five most costly hurricanes in the US, according to the National Oceanic and Atmospheric Administration (NOAA): 1, Katrina 2005 ($200bn damage; 1,200 deaths); 2, Harvey 2017 ($160bn; 107); 3, Ian 2022 ($118.5bn; 161); 4, Maria 2017 ($115.2bn; 3,059); 5, Sandy 2012 ($88.5bn; 233).

Nasa astronauts aboard the International Space Station (ISS) orbiting 260 miles above Earth recorded this video of Hurricane Helene in the Gulf of Mexico on Thursday.

The footage shows the storm, at the time packing winds of 100mph, beginning to grow in size and intensity in the hours immediately before landfall.

ISS and satellite imagery from space have proven invaluable following previous hurricanes, helping officials to assess the extent of damage and plan recovery and restoration efforts.

Helene might not be the strongest hurricane to ravage the US, but it’s certainly one of the largest.

According to the National Hurricane Center (NHC), it’s bigger in size than 90% of all other tropical cyclones to have formed in the Atlantic or Caribbean in the past 20 years, with a wind field almost 500 miles wide. That’s the same distance from Indianapolis to Washington DC, CNN says, or from London to Glasgow.

It means areas far inland that usually escape the ravages of even the most powerful of storms will be affected this time. In a lunchtime advisory Thursday, NHC senior hurricane specialist John Cangialosi said strong gusts could be expected in northern Georgia, the Carolinas, and the southern Appalachians:

Helene is a very large hurricane. In fact, comparing the system with previous hurricanes in the Gulf of Mexico over the past couple of decades, Helene is at the upper bound in terms of size.

As a result, storm surge, wind, and rainfall impacts will extend far away from the center and well outside the forecast cone, particularly on the east side.

By Thursday evening, the entire state of Florida was under storm watches or warnings, and governor Ron DeSantis had declared a state of emergency in 61 of 67 counties.

North Carolina’s governor Roy Cooper warned of “significant flash flooding, landslides, damaging debris flows, slope failures across steep terrain and river flooding” in his state.

“Even areas that typically don’t experience it may see flooding,” he said.

At least 3 killed as Hurricane Helene makes landfall