The powerful storm system, which is weakening, has brought severe flooding, winds and storms.
- Hurricane Ian, which peaked at a category four storm, is bringing severe flooding, high winds and storm surges to the Florida coast
- It is now losing power as it moves inland, and has been downgraded to a category one system
- More than two million customers in Florida have no electricity as a result of the hurricane
- It made landfall on Wednesday afternoon with maximum sustained wind speeds of 241km/h (150mph) near the city of Fort Myers
- Florida Governor Ron DeSantis warns people in the storm's path to get ready for "a nasty, nasty" couple of days
- US Border Patrol is looking for up to 23 migrants missing after their ship sank during the storm
- The hurricane barrelled through Cuba on Tuesday, killing two people and shattering the country's electrical grid
Hurricane Ian heads towards Disney World
Hurricane Ian is now heading through central areas of Florida, raising concerns for theme parks around Orlando such as Disney World.
Jason Allen is a CBS correspondent reporting from Tampa, on the western side of the state.
He told the BBC that things were much calmer and drier where he is, but plenty of flash flood warnings were still in place.
He added that residents in eastern areas such as Daytona Beach were now braced for the storm and those trapped in flooded buildings further south, where the storm first hit, are still awaiting rescue.
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All flights cancelled at Jacksonville International Airport
Jacksonville International Airport, in north-east Florida, cancelled all of its flights scheduled for Thursday.
In a tweet, the airport said its terminal will be closed and passengers should contact their airline for rebooking options.
On Wednesday alone, some 1,961 flights within, into and out of the United States were cancelled, according to the website Flightaware.
Screaming winds at Fort Myers
Meteorologist Mike Seidel, who works for the US-based Weather Channel, has posted dramatic video from storm-battered Fort Myers.
The ferocious winds can clearly be heard as they whip the Florida coastline.
He tweeted: "I haven't experienced anything close to this in over 30 years."
Nasa is watching what's happening with Hurricane Ian very carefully - because it has delayed a launch to the International Space Station (ISS).
The Crew-5 mission with Nasa and SpaceX is taking a four-person crew to the ISS, and was originally meant to launch from the Kennedy Space Centre on Florida's east coast on Monday.
Nasa says it will now launch no earlier than 4 October.
“Mission teams will continue to monitor the impacts of Ian on the Space Coast and Nasa's Kennedy Space Center in Florida and could adjust the launch date again, as necessary,” the American space agency said in a blog post.