Atlanta-based Delta Air Lines has cancelled about 1,350 flights ahead of storms.
That includes about 140 flights from Atlanta cancelled for Friday and about 100 more for Saturday.
Delta is cancelling about 40 Atlanta flights Friday evening "due to the frozen precipitation likely arriving here earlier than projected," said spokesman Michael Thomas.
The 1,200 cancellations from Friday through Sunday include flights to Charlotte, Richmond, Baltimore, Washington Dulles, Washington Reagan and New York.
The Charlotte airport was closed Friday, with operations expected to resume Saturday morning, and the situation is similar in Richmond, Raleigh-Durham, Roanoke, Knoxville and other airports in the region, according to Delta.
The Washington, D.C. airports expect 15 to 20 inches of snow, Delta said, and the Metro transit system will be shut down Saturday and Sunday. The airline has cancelled its schedule of departures from Washington for Saturday.
And Delta said it is cancelling most of its international flights in New York for Saturday. It expects to operate some flights Saturday evening.
Those with Delta flights booked to, from or through affected airports can change their travel plans without paying a change fee to avoid the storm, with certain restrictions.
Delta said it is sending a "de-ice go team" of workers to Atlanta and the Northeast to help with operations.
Dallas-based Southwest Airlines, the second largest carrier in Atlanta, said across its system, it canceled about 500 flights for Friday, 600 for Saturday and 100 for Sunday. It said it would adjust plans as the storm progressed.
Southwest did not plan any changes targeted at Atlanta, but those with flights booked to cities harder hit by storms could still see their flights cancelled.
Southwest said it was ceasing flights to Baltimore and Washington, D.C.-area airports on Friday afternoon and to New York and Philadelphia on Friday evening, with no flights Saturday, and tentatively planned to resume service Sunday morning.
Hartsfield-Jackson is telling passengers to check with their airlines for their flight status before coming to the airport, and to allow plenty of time to get through parking and security.