The cruise lines have canceled or changed the itineraries for a number of other cruises.
Hurricane Dorian has killed at least five people in the Bahamas.
The Category 3 storm could begin to impact Florida as soon as Tuesday evening, forecasters have said.
Six Royal Caribbean ships that boarded in Orlando, Miami, or Fort Lauderdale will return later than expected, the company said on its website. The Harmony of the Seas faces the longest delay, as it is scheduled to return to Orlando on Thursday, four days later than originally planned.
"Please know, our guests and crew safety is our top priority and being onboard a ship is one of the safest places to be during a storm," the company said.
One of the ship's passengers told the CBS affiliate WTVR that the storm had delayed her kids' return to school and her return to work.
"My kids are going to miss the first week of school, my dogs are in a kennel so I'm anxious to get back to them, and we also have two businesses," she told the station.
Disney Cruise Line's Disney Dream will return to Orlando on Thursday, one day later than expected.
"The safety of our guests and crew is always our foremost concern," the company said on its website.
Norwegian Cruise Line is extending its August 25 Norwegian Breakaway cruise by two days and changing its final destination from Miami on September 1 to New Orleans on September 3.
"While it is our every intention to maintain the original itinerary as much as possible, the security of everyone on board always takes precedence," the company said on its website.
While Carnival Cruise Line has not yet extended any of its cruises, it said on its website that the Carnival Ecstasy may not return to Jacksonville on Thursday as planned.
In addition to the extended cruises, the cruise lines have canceled or changed the itineraries for a number of other cruises.
Hurricane Dorian has killed at least five people in the Bahamas as it nears Florida. The Category 3 storm could begin to impact Florida as soon as Tuesday evening, forecasters have said.
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