Hundreds of Christmas flights canceled

(CNN) -- Delta Air Lines has pre-emptively canceled approximately 500 Christmas Day flights, a company spokesman said, as it and other U.S. airlines work to get ahead of a storm that's threatening the East Coast.

Morgan Durrant, a Delta spokesman, said Friday that the airline has canceled roughly 300 flights in and out of Atlanta and 200 more elsewhere around the country.

Delta also has joined Continental, United and AirTran in waiving penalties for travelers who have to reschedule their trips over the weekend.

The mid-Atlantic and Northeast could see combinations of rain, sleet and snow, with the heaviest amounts of precipitation in highest elevations, CNN meteorologists said.

It's too soon to say how serious the storm system will become, forecasters say, adding that by Saturday morning the scenario will be clearer.

Across New England, there could be 6 to 8 inches of snow and isolated amounts of 10 inches into late Sunday and Monday.

From late Sunday into Monday, Boston could see mostly rain, New York could get a dusting of snow, and Philadelphia could get 2 to 4 inches of snow, forecasters say. Atlanta might have sleet and snow late Saturday into Sunday.

United Continental Holdings Inc., parent company of United and Continental airlines, said that "customers scheduled on flights to, from or through the impacted areas may reschedule their itinerary with a one-time date or time change, and the change fees will be waived."

For canceled flights, "a refund in the original form of payment may be requested," it said.

Mike Trevino, a United Airlines representative, confirmed that United will issue a waiver for customers traveling Saturday through Monday to areas affected by weather.

"Customers will not be charged a change of ticket fee. No flights have been canceled in advance of the storm," he said.

The offer applies to travelers with tickets purchased on or before Thursday and going to, from or through airports serving Newark, New Jersey; New York City, Philadelphia, Pittsburgh, Boston, Washington, Baltimore and Atlanta.

Delta is offering customers whose flight plans may be affected by winter weather across the Southeast and East "the ability to make one-time changes to their travels schedules without fees. Delta's weather advisory encourages customers to consider postponing or rerouting their travel to avoid possible inconvenience from expected flight delays."

Customers "booked on Delta-ticketed flights to, from or through" several cities "may immediately rebook for travel before or after their original travel dates as long as new flights are ticketed and rescheduled travel begins by Dec. 29."

The cities are Atlanta, for travel booked for Saturday and Sunday; and Baltimore, Boston, Newark, New York and Washington for travel booked for Sunday and Monday.

AirTran is also waiving penalties for passengers traveling to and from Atlanta from 2 p.m. Saturday to noon Sunday, and on Sunday and Monday for other cities "as long as travel is completed within three days from the date of the original scheduled departure date or five days after the original scheduled departure date, based on space availability, without fees or fare adjustments."

The locations are Allentown, Pennsylvania; Atlantic City, New Jersey; Baltimore; Boston; Buffalo, New York; Harrisburg, Pennsylvania; New York; Philadelphia; Pittsburgh; Portland, Maine; Richmond, Virginia; Rochester, New York; Washington; and White Plains, New York.