Residents in parts of Miami have been ordered to leave their homes as Hurricane Irma barrels towards Florida with potentially catastrophic winds.
Florida Governor Rick Scott has declared a state of emergency and strongly urged people on Wednesday to leave if asked to do so by officials.
He warned Irma was "bigger, faster and stronger" than Hurricane Andrew, the last category-five storm to hit the state 25 years ago.
Mayors in Miami-Dade and Broward counties issued mandatory evacuation orders for barrier islands and low-lying mainland areas in the metro area of six million, where forecasters predict the hurricane with winds of 290km/h could strike by early Sunday.
The most powerful hurricane recorded in the Atlantic caused deaths and injuries, destroyed homes and flooded streets as it roared through islands in the northern Caribbean.
The US National Hurricane Center said it could rake the entire length of Florida's east coast and push into Georgia and the Carolinas.
"This thing is a buzz saw," Colorado State University meteorology professor Phil Klotzbach said.
"I don't see any way out of it."
An estimated 25,000 people or more left the Florida Keys after all visitors were ordered to clear out, causing bumper-to-bumper traffic.
Amid the dire forecasts and the devastating damage done by Hurricane Harvey less than two weeks ago in Houston, some people who usually ride out storms in Florida seemed unwilling to risk it this time.
"Should we leave? A lot of people that I wouldn't expect to leave are leaving. So, it's like, 'Oh, wow!'" said Martie McClain, 66, who lives in the South Florida town of Plantation.
