Tens of thousands of people are fleeing the US state of Louisiana as Hurricane Ida closes in from the Gulf of Mexico.
Ida is now a category four hurricane, one below the highest level, with up to 140mph (225km/h) sustained winds.
It is expected to make landfall on Sunday evening, bringing a "life-threatening" storm surge. It could be stronger than Hurricane Katrina, which devastated much of New Orleans in 2005.
Traffic jams clogged motorways as residents heeded orders to evacuate.
The National Hurricane Center said "potentially catastrophic wind damage and flooding rainfall will impact portions of the northern Gulf coast beginning later this morning" (Sunday).
Governor John Bel Edwards warned the storm could be one of the biggest to hit the state in 150 years.
"Your window of time is closing," he warned residents on Saturday.
"By the time you go to bed tonight you need to be where you intend to ride the storm out and you need to be as prepared as you can be, because weather will start to deteriorate very quickly tomorrow."
The governor of neighbouring Mississippi has declared a state of emergency.
President Joe Biden said Ida was "turning into a very, very dangerous storm" and the federal government was ready to provide help.