Major airlines serving Hartsfield-Jackson International Airport canceled hundreds of flights to parts of the Northeast as a winter storm approached the region only a week after “superstorm” Sandy left death, destruction and major power outages.

Delta Air Lines, AirTran and Southwest joined United, American and other major carriers in canceling or delaying flights Wednesday and into Thursday.

Delta said it canceled at least 300 flights Wednesday to the two major airports in New York City — John F. Kennedy International and LaGuardia — in addition to flights to seven other airports, including Newark International in New Jersey and Philadelphia International.

Atlanta-based Delta, the largest carrier serving Hartsfield-Jackson, said it is closely monitoring the nor’easter and conditions along the storm’s expected mid-Atlantic path. The airline said travelers are entitled to a refund for canceled or significantly delayed flights. They may also make a one-time change to their ticket without incurring a fee.

Fees also are being waived at AirTran, the second-largest carrier at Hartsfield-Jackson, and Southwest, which acquired AirTran last year.

AirTran canceled flights to LaGuardia and Philadelphia on Wednesday and into Thursday. Southwest canceled flights to Newark; LaGuardia; Philadelphia; Hartford, Conn.; and Long Island, N.Y., on Wednesday and into Thursday.

United is the largest carrier with flight cancellations, at least 500. The airline warned the weather is likely to trigger more delays and cancellations throughout the region.

The National Weather Service said “a low-pressure system off the mid-Atlantic coast will continue to strengthen as it moves north, bringing rain, snow, and/or a mixture of precipitation to areas across the northern mid-Atlantic and Northeast, as well as wind gusts as high as 60 mph along the coast.” Six to 12 inches of snow could fall across the interior sections of New England. Coastal flooding also is possible.

About 1,100 workers from Georgia Power remain in New York and Pennsylvania, helping other crews from around the country restore power to just under a million people in the Northeast, according to spokeswoman Carol Boatright.

“We’ll be there until we get pretty much everyone restored,” Boatright told The Atlanta Journal-Constitution. The crews have been there for about a week and the spokeswoman said they’ll remain if they are needed to help with any problems the nor’easter leaves behind.

The storm will have little major precipitation impact on metro Atlanta’s weather, although some parts of metro Atlanta saw a little sleet and snow flurries on Wednesday. Temperatures were expected to dip into the 30s overnight and into early Thursday, with frost possible in metro Atlanta and areas farther north. The forecast calls for clear skies the remainder of the week with a high of 60 degrees Thursday but reaching 70 by Sunday. Lows will be in the upper 30s Thursday to the mid to upper 40s by Sunday.