At least 43 people have been killed across the southeast US since Storm Helene made landfall in Florida last night - including first responders in South Carolina and Georgia who died trying to save others
Streets are underwater in parts of Georgia, where the National Weather Service has issued flash flood warnings and warned more than a million people are at risk. At least 15 have died in the state
In Florida, clean up operations are under way, with a Cedar Key resident telling the BBC his home "miraculously survived" while others "are missing or flattened" entirely
One of the biggest storms to ever hit the Gulf Coast, Helene has barrelled across Georgia, Tennessee and the Carolinas after devastating Florida with fierce winds and flash flooding.
Originally a category four hurricane, Helene was downgraded to a tropical storm on Friday and then a tropical depression
Dramatic flooding and rescues as Hurricane Helene hits Florida
Nasa has released images of what Hurricane Helene looks like from space, as the storm makes its way towards Florida.
Image source, NASA
Image source, NASADriving rain has already flooded roadways in the state and closed down both Tampa International Airport and Tallahassee International Airport.
We're continuing to monitor the situation and will bring you the latest.
Image source, NASA
Isabelle Gerretsen
Senior journalist, BBC Future
Helene quickly intensified from a category one storm into a catastrophic category three hurricane.
Rapid intensification of hurricanes is becoming more common as oceans get hotter. The heat in the oceans is the fuel that powers storms - so the warmer the water is, the more energy they can pump into hurricanes.
Storms are now 25% more likely than they were 40 years ago to be classified as a major hurricane, reaching wind speeds of 111mph (180km/h).
With record-breaking ocean temperatures every day over the past year, scientists say more intense hurricanes are unsurprising.
Flooding in Florida ahead of Hurricane Helene landfall
Nadine Yousif
North America reporter
Cainnon Gregg works as an oyster farmer in Wakulla County on Florida’s Big Bend, where Hurricane Helene is expected to make landfall in a few hours.
He told me that he had spent the last few days trying to protect his oyster farm by sinking it onto the ocean bed.
It was once destroyed during Hurricane Michael, a category 5 hurricane that hit the Florida panhandle in 2018, and Gregg said he is determined to learn from that lesson.
“Hopefully, and nothing is for certain, the farm is sitting nice and safe on the bottom,” he said. “But anything could happen.”
To weather the storm, Gregg will be hunkering down in his hometown of Tallahassee with a friend who has a shelter.
The city is also in the hurricane’s projected path, and it has not experienced a storm of this magnitude in recent memory.
“Right now it’s pretty much a ghost town. Everything’s closed. Everything’s boarded up.” he said.
“Even Waffle House is closed,” he added, referencing the ubiquitous US restaurant chain that is known for operating 24 hours, 365 days a year, rain or shine.
Federal Emergency Management Agency (FEMA) Administrator Deanne Criswell has briefed President Joe Biden about the storm.
Earlier today, Criswell told reporters at the White House that FEMA have been preparing for days for Hurricane Helene.
"This is going to be a multi-state event with the potential for significant impacts from Florida all the way to Tennessee," she said.
Criswell said she will head to Florida tomorrow to see the impact of the storm first-hand.
Hurricane Helene is expected make landfall at Florida's Big Bend at 19:30 local time (00:30 BST).
The storm is currently a category three, with 120mph (195 km/h) winds.
The storm surge is expected to reach as high 20 feet (6m) in some areas and higher than 9ft (2.7m) in areas near the city of Tallahassee.
As much rainfall as 18 inches (45 cm) could fall in some parts, potentially causing serious flash flooding.
Image source, Getty ImagesJamika Bowens and James Womack (R) watch waves break as Hurricane Helene passes offshore in St. Petersburg, Florida
Image source, ReutersWaves batter a seawall in front of a house in Eastpoint, Florida ahead of Hurricane Helene's landfall
Image source, Getty ImagesWaves from the Gulf of Mexico crash on shore as Hurricane Helene churns offshore at St. Pete Beach, Florida.
Image source, Getty ImagesVehicles drive along a flooded street in St. Pete Beach
Nadine Yousif
North America reporter
Michael Bobbit, a clam farmer in the island of Cedar Key on Florida's Big Bend, said that some people in his community have decided to stay behind despite the warnings.
“The last several hours have really just been a frantic effort to beg people to leave,” Bobbit, 48, told the BBC. “Here in Florida, we sort of believe that we’ll just ride it out, it’s no big deal. But this is not one of those storms.”
He added that locals have been trying, "to sandbag as many buildings as we can," as well as board up windows and get the island's clam farms secured.
"The mood is sombre," Bobbit said. "A lot of people when they’re leaving the island are hugging each other and crying, saying ‘I hope we have a home to go back to.'"
Helene to make landfall in Florida as category 4 hurricane
Florida’s governor has been warning about Hurricane Helene for the last couple of days, describing it as “very large” and saying it will bring tropical storm conditions to much of his state.
“Every minute that goes by brings us conditions that are simply going to be too dangerous to navigate,” Ron DeSantis said earlier - adding that people should expect flight delays and cancellations.
About 14 tornado warnings were issued overnight on Wednesday, with DeSantis saying more are likely in the coming day.
He also said Tallahassee, Florida’s capital city of 200,000 residents, could be significantly affected if the hurricane makes landfall on the city as expected.
“This area has not had a major hurricane hit in quite some time, and nobody in recent memory has seen a storm of this magnitude hit,” DeSantis said, urging residents in impacted regions to leave as soon as possible.
Sam Hancock
Live page editor, in Washington DC
A number of evacuation orders are in place across Florida as the state prepares for the arrival of Hurricane Helene.
The storm had grown into a category three hurricane and is expected to make landfall south of state capital Tallahassee as a category four hurricane later on Thursday.
Floridians - especially those living in coastal areas along Helene’s path - have been warned that it will bring an "unsurvivable" storm surge and “life-threatening” weather.
Florida Governor Ron DeSantis says conditions “are simply going to be too dangerous to navigate“.
We’re keeping an eye on the storm as it develops and will bring you the latest lines, plus any relevant analysis and reaction, right here.
Stay tuned.