Wind and rain are whipping North Carolina's coast, after the storm made landfall
Authorities have confirmed at least three deaths linked to the storm
Evacuation warnings are in place for up to 1.7 million people across South Carolina, North Carolina and Virginia
Eight months' worth of rain is expected to fall in three days
Serious flooding is still expected even though it has been downgraded to a tropical storm with 70mph (110km/h) winds
The BBC's Darren Bett takes a look at the updates around Hurricane Florence, as torrential rain and damaging winds begin lashing parts of the East Coast.
Hurricane Florence approaches Carolinas
Image source, NOAAHurricane Florence off the coast of the US
The relationship between climate change and hurricanes is a complex one.
Warmer seas power hurricanes. So as the temperature of ocean water goes up, we might expect the intensity of hurricanes to increase in future.
A hotter atmosphere can also hold more water, so this should allow hurricanes to dump more water on affected areas.
But there are so many factors that contribute to these rare events, it has been difficult to tease out clear trends from the data.
Read more on how climate change could affect hurricanes here.
The US Air Force Reserve Hurricane Hunter team flew into Florence again, capturing this eerily calm footage of the storm's eye.
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Reports of damage caused by storm surge during high tide in North Carolina are already appearing.
The National Hurricane Center says the greatest storm surge inundation will probably be between Cape Fear and Cape Hatteras in North Carolina. In these areas, water levels could rise to 13ft (4m).
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ABC 13 News tweeted video of a terrifying moment when storm surge nearly carried off a photographer in North Carolina.
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South Carolina Governor Henry McMaster warned his state that conditions "will not be normal for many days".
"If you’re going to leave - and you should leave - if you haven’t left yet, you should leave now. Time is running out...Power will be out for a long time, think about what you need."
According to officials, 420,000 people have been evacuated in the state so far.
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The Weather Channel has tweeted this frightening graphic which illustrates how high raging flood levels may get.
It's worth a full watch.
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The BBC's Paul Blake captures the storm battering Morehead City on the North Carolina coast.
Hurricane Florence hits Morehead City, North Carolina
Image source, AFPHurricane Florence evacuation shelter at Conway High School in South Carolina
Joan Meacham, acting director of the state department of social services, said South Carolina can shelter an additional 35,000 people or more, according to Reuters.
Meacham said 61 shelters are now open, housing over 4,000 evacuees.
Officials estimate 421,000 have evacuated from South Carolina's coastal areas.
Image source, Getty ImagesA Fema member prepares for the storm's arrival
The Federal Emergency Management Agency (Fema) has set up a website to counter several rumours that have been spreading ahead of the storm.
Many of the rumours cover what animals and pets are permitted at emergency shelters.
Other entries on the "rumor control" website seek to reassure people that Fema has the money and resources to manage the aftermath of Florence.
Image source, Getty ImagesThe National Weather Service for Morehead City, North Carolina, shared this local footage of ocean water making its way inland as Florence nears the coast.
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Why do people ignore hurricane warnings?
Swells are picking up as the storm moves closer to making landfall.
A camera at the Frying Pan, a decommissioned lighthouse along the North Carolina coast, is currently filming a slowly eroding US flag.
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Several businesses offered free plywood boards for people to cover their windows ahead of the storm.
The BBC's Mat Morrison is in Charleston, South Carolina, where he has seen plywood boards telling previous hurricanes (Matthew and Irma) to "go away".
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Image source, Getty Images
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The state's emergency management team reports as of this afternoon, 16,711 residents were without power. The areas with the most outages are coastal Carteret, Craven and Pender counties.
Earlier, Governor Roy Cooper tweeted that new shelters for evacuees are opening up across North Carolina.
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Hurricane Florence: 'Everybody's frightened'
Image source, AFP/GettyPolice blocked parts of the highways to allow residents to evacuate in recent days.
On Monday, South Carolina officials announced they would not remove inmates from at least two prisons , externalinside mandatory evacuation zones.
"In the past, it's been safer to leave them there," a spokesman for the South Carolina Department of Corrections said.
Many on social media are drawing parallels with the devastating Hurricane Katrina, in 2005, when thousands of inmates endured terrible conditions in a facility that had not been evacuated.
The BBC's Paul Blake captured this footage of stormy waters in Morehead City, North Carolina, a port town north of Wilmington that's expected to see winds of over 75mph (120km/h) this afternoon.
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Image source, ReutersEvacuating residents spray paint prayers on boarded up homes and businesses in the Carolinas
Nearly 1.7 million Americans have been ordered to evacuate, although some people have chosen to stay behind.
The most recent graphs show that the storm will stall out after making landfall, and may remain in the same place for nearly 36 hours, dumping an average of 20-30 inches (50-75cm) of rain.
Rainfall of up to 40 inches may affect some isolated regions as the storm moves south across South Carolina and into Georgia.
BBC World News America's Laura Trevelyan says serious rains are starting to pour down on Wilmington, North Carolina.
Florence was initially predicted to make landfall there, though current models say it could be closer to Cape Fear, North Carolina, some 40 miles (64km) away.
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