Travelers can expect more cancellations next week as Irma heads toward the world's busiest airport.
The latest National Oceanic and Atmospheric Administration forecast shows Irma weakening to a tropical storm and passing over northwest Georgia on Tuesday morning. While it would be a weaker storm at that point, it could still disrupt operations at Hartsfield-Jackson Atlanta International Airport.
As a tropical storm, Irma could bring winds strong as 73 miles per hour. The size of the plane and direction of the wind can determine whether a plane can take off or land in heavy winds. A spokesman for Miami International Airport says air traffic control closes if there are sustained winds of 55 miles an hour or higher.
More than 104 million travelers passed through Atlanta's airport last year, making the Delta Air Lines hub the world's busiest for passenger traffic, according to Airports Council International. Nearly 2,500 planes take off and land from the airport each day.
A spokesman said the airport is preparing kits with toothbrushes for passengers who might be stranded there and will ensure that at least one food and beverage provider will remain open 24 hours a day in each terminal. The airport may close taxiing space to allow airlines to park if they are unable to take off during the storm.
The airport is in the midst of an expansion so workers are scrambling to secure any construction materials that would pose safety risks in high winds.
Meanwhile, airlines including Delta, United, American and JetBlue are winding down operations in southern Florida on Friday afternoon or early evening as Irma, now a powerful Category 4 hurricane, approaches the state. NOAA forecasts the storm will make landfall as early as Sunday. Carriers added flights and capped fares ahead of the storm, after travelers complained of sky-high prices.
Atlanta would be the third major airport hub to be hit by a major storm in a month. Hurricane Harvey knocked out service at United hub George Bush Intercontinental Airport in Houston last month. The airline said the storm would cost it $400 million in revenue this quarter.
Irma is expected to plow into south Florida, where American Airlines operates a hub out of Miami International Airport.
The storm's exact path once it makes landfall is still unknown but flight cancellations due to Irma, currently at more than 4,000, will likely swell if the storm hits the much larger Atlanta hub.
As a weakened tropical depression, NOAA expects the storm to pass over central Tennessee early Wednesday, east of Memphis, home to FedEx and the world's second-busiest airport for air cargo after Hong Kong.