As Florida prepares to bear the brunt of Hurricane Ian, more than 2,000 flights in the US have been cancelled.
About 350 flights either into the country, inside it or leaving it were cancelled on Tuesday, data from flight-tracking website FlightAware.com showed. More than 1,700 have been cancelled for Wednesday.
Hurricane Ian entered the Gulf of Mexico on Tuesday after making landfall in Cuba, and is forecast to strengthen into a Category 4 hurricane.
The storm is expected to deliver winds up to 209 kilometres an hour and 60 centimetres of rain to the Tampa area of Florida into Thursday evening.
It will be the city's first direct contact with a hurricane in more than a century.
Airports in the cities of Tampa and Clearwater halted operations on Tuesday. Orlando International will cease flights on Wednesday morning.
US President Joe Biden's trip to Fort Lauderdale and Orlando was also cancelled because of the hurricane, the White House said.
Mr Biden directed the Federal Emergency Management Agency to ensure support was ready to be provided to areas of Florida so they could respond to the storm's damage, the White House said after he called the cities' mayors.
The Federal Aviation Administration said it was “closely monitoring” Hurricane Ian's path.
Southwest Airlines announced it had temporarily halted operations in Havana, Cuba.
The US airline said it would stop flying from the Florida cities of Tampa, Sarasota and Fort Myers on Tuesday evening through to Thursday.
American Airlines has issued travel alerts for airports in the western Caribbean and Florida, which are forecast to be in Hurricane Ian's path. The carrier has also capped fares for one-way flights out of Florida.
Disney World announced on Tuesday night that its theme parks will be closed on Wednesday and Thursday.
“We are continuing to closely monitor Hurricane Ian and are making necessary operational adjustments to maintain the safety of our guests and cast members,” the resort said.
The Associated Press contributed to this report
