Hurricane Irma regained its strength as it closed in on Florida, with devastating winds and life-threatening storm surges prompting one of the largest evacuations in US history.
The Category 4 hurricane had maximum sustained winds of 130mph, the National Hurricane Centre said, and was on path that would take it along the state's Gulf of Mexico coast, near population centres including Tampa and St Petersburg.
Irma, which killed at least 22 people in the Caribbean, was considered a life-threatening danger to Florida as well, and could inflict a natural disaster causing billions of dollars in damage to the third-most-populous US state.
Officials in Florida have ordered a total of 6.3 million people, or about a third of the state's population, to evacuate, creating massive traffic jams on highways and overcrowding shelters.
"This is a storm of enormous destructive power, and I ask everyone in the storm's path to heed ALL instructions from government officials," President Donald Trump said on Twitter.
Florida Governor Rick Scott had warned residents in the state's evacuation zones that "this is your last chance to make a good decision."
Irma was expected to rip through Florida's southwestern archipelago as a Category 4 storm, the second-highest designation on the Saffir-Simpson scale. It should then move inland over the Florida panhandle and southwestern Georgia on Monday afternoon, the NHC said
Wind gusts near hurricane force began to batter the Florida Keys late on Saturday, the NHC said, with Key West seeing gusts of more than 80 mph.
It has put out a hurricane watch and warning as well as a tropical storm warning for almost all of the state into Georgia and South Carolina - an area where about 20 million people live.
Storm surges pushed by a high tide were forecast to be as high as 15ft (4.6m) for low-lying area along the state's west coast on Sunday, which could produce catastrophic flooding for thousands of homes.
The city of Miami imposed a curfew until 7am on Sunday and more than 260,000 customers in Florida were without power on Sunday morning, utilities reported.
Irma comes just days after Hurricane Harvey dumped record-setting rain in Texas, causing one of the costliest natural disasters in US history.
