Hurricane Helene prompts airlines to issue travel alerts: Here's what you need to know

TAMPA -- Hurricane Helene has prompted an array of weather alerts from airlines to cruises to ensure travelers can safely avoid areas where the Category 2 storm is expected to hit.

Airlines and cruises with routes in the region began taking preventative measures earlier this week and sent more updates about the potential impacts to itineraries on Thursday as the storm barrels towards Florida and the Southeast.

The National Hurricane Center said there is "significant additional strengthening expected before landfall" on Thursday morning, adding "there is danger of life-threatening storm surge along the entire west coast of the Florida Peninsula and Florida Big Bend."

See below for a full list of airports, cruise ship ports and other areas that have been impacted.

Air travel impacted ahead of Hurricane Helene: Airport closures, airline changes

Nearly 900 flights across the country have already been canceled due to Helene, according to Flight Aware, with the biggest impacts seen in Tampa, Fort Myers, and Atlanta as of time of publication.

RELATED: Eagles fans travel to Florida before Hurricane Helene makes landfall

While all airlines are required to offer a full refund to customers if a flight is canceled or significantly delayed due to reasons within the airline's control, per the Department of Transportation, that rule does not encompass weather-related delays or cancellations.

Florida airport closures

As of time of publication, three major Florida airports have announced temporary closures due to the storm.

Tampa International Airport suspended all commercial and cargo operations at 2 a.m. Thursday and said it will remain closed to the public until it can assess any damage after the storm.

Tallahassee International Airport and St. Pete-Clearwater International Airport have also closed and officials at each said they will be closed to the public until damage assessments are completed after the hurricane.

Other regional airports including Northwest Florida Beaches International Airport near Panama City Beach, Orlando International Airport and Jacksonville International Airport are currently open but have advised all travelers to check with airlines directly for the latest flight status and information.

Airlines prepare for Hurricane Helene, issue travel advisories

American Airlines
American issued a travel alert for the Gulf of Mexico that affects 23 airports, with 16 of those in Florida, including Tampa and Sarasota.

For passengers who bought tickets of any fare class before September 23 for travel between Sept. 24-27, the change fee will be waived.

Changes must be booked by September 27, and travel must be for the same travel origin and destination.

Delta Air Lines
The Atlanta-based carrier shared a weather advisory for Tropical Storm Helene due to forecasted path, explaining that "travel may be impacted to/from/through" 17 destinations.

"Check flight status frequently for up-to-the-minute information about your flight plans, or get updates sent directly to your mobile device or by email with One-Time Notification," the airline stated.

As of time of publication, the advisory covers 12 airports in Florida, including Jacksonville, Sarasota and Tampa, as well as select airports in Alabama, Georgia, South Carolina, Mexico and Cuba.

Travelers scheduled to fly through one of the listed airports from September 25 through 27 can rebook tickets by Monday, September 30.

JetBlue Airways
JetBlue has issued a travel alert that flights to multiple Florida destinations have been canceled on Thursday and Friday: Tallahassee and Tampa, as a result of the airport closures, as well as Fort Myers. The airline also canceled all Sarasota flights for Thursday.

All JetBlue flights to Orlando and Jacksonville are operating at this time, as well as Atlanta, Savannah and Charleston.

The airline said it will waive change, cancel fees, and fare differences for customers with travel on Sept. 26-27. Flights can be rebooked by Wednesday, Oct. 2.

Southwest Airlines
Southwest Airlines issued the travel advisory "based on the forecasted weather conditions" where the carrier's "scheduled service may be disrupted."

It lists 10 Florida airports where scheduled service may be disrupted through Friday, plus Atlanta, Charleston, Charlotte, Greenville/Spartanburg, Myrtle Beach, Nashville and Savannah.

United Airlines
The Chicago-based airline listed eight airports in Florida, plus one in Cuba and three more in Mexico, that would be impacted.

Passengers who purchased a plane ticket before Monday, September 23, for travel on Tuesday through Friday, September 24-27, to, from, or through any of the affected airports can rebook without a change fee for travel through Friday, October 4.

Frontier Airlines
The budget carrier issued a travel alert for passengers traveling in or out of six Florida airports on both Thursday and Friday, September 26-27.

Royal Caribbean, Carnival and MSC Cruises change course, update itineraries

The sunshine state and its ports are at the center of the cruise industry, accounting for nearly 60% of all U.S. embarkations, according to the Cruise Lines International Association, where multiple sailing itineraries have been impacted by Hurricane Helene.

One ship is currently stuck at sea, while two more are skipping planned stops and multiple ports, including Port Canaveral, have closed as a result of the inclement weather.

Royal Caribbean
Five ships routes have been impacted, according to a travel update from the cruise line's parent company Royal Caribbean Group.

Serenade of the Seas, which disembarked from Tampa on Sunday, changed both its Tuesday and Wednesday stops in Cozumel and Costa Maya for Freeport and Nassau, Bahamas. The ship is now set to return to Tampa on Sunday, two days later than originally scheduled delaying the next scheduled voyage that was originally set to leave on Friday.

"Due to Hurricane Helene and the planned closure of Port Tampa, our previous sailing will be delayed in returning," the cruise line stated. "As a result, our sailing will now depart on Sunday, Sept. 29 at 4:00pm. We kindly ask that you arrive during the arrival window you originally selected for an on-time departure."

Independence of the Seas departed Miami on Saturday and changed Tuesday's planned stop in Cozumel to Nassau, Bahamas.

Mariner of the Seas, which left Saturday from Galveston, Texas, also swapped out Cozumel on Tuesday for a day at sea.

Wonder of the Seas will scrap most of its planned stops, skipping Cozumel, Roatan in Honduras, and Costa Maya. The ship, which left from Florida's Port Canaveral on Sunday, will add stops in St. Thomas and St. Maarten instead.

Grandeur of the Seas will visit Nassau and Freeport in place of planned Wednesday and Thursday stops in Costa Maya and Cozumel. The cruise departed from Tampa on Monday.

Carnival Cruise Line
Both Tampa and Jacksonville ports closed Wednesday evening ahead of Hurricane Helene's projected landfall.

"Our Fleet Operations Center in Miami continues to actively monitor Hurricane Helene, which is now entering the Gulf of Mexico," the company said on its website. "The safety of our guests and crew remains our priority and our ships are sailing a safe distance from the storm."

Given the forecasted track of Helene over the next few days, Carnival announced that eight ships' itineraries are currently under watch. Click here for full details and planned changes.

Disney Cruise Line
Disney Fantasy left from Port Canaveral on Saturday and reportedly canceled its Tuesday call at George Town to replace it with a sea day, USA Today first reported.

The Disney Wish itinerary was originally scheduled to arrive at Port Canaveral on Friday morning with its next cruise departing Friday afternoon, but as of time of publication, "Port Canaveral is closed and has ceased all waterside and vessel shoreside Port operations until further notice."

Disney Cruise Lines did not immediately respond to ABC News' request for comment.

Disney is the parent company of ABC News.