By LUCAS L. JOHNSON II
NASHVILLE, Tenn. (AP) - With a rare Christmas snowfall descending on the Southeast and likely headed for the Mid-Atlantic, airlines canceled hundreds of flights and urged travelers to rethink their plans, while travel authorities warned of potentially dangerous roads.
After blanketing parts of the Midwest and hampering motorists there on Christmas Eve, the storm dipped south late Friday. Winter weather advisories were in effect Friday night from Missouri to West Virginia and from Iowa and Illinois down to Georgia and the Carolinas.
The wintry weather is the result of a low pressure system moving along the Gulf coast. It is expected to intensify and move northeast on Sunday to the mid-Atlantic states and New England. Just how far off the coast the low pressure system stays will determine whether areas such as Washington, D.C. get hit with snow on Sunday, said National Weather Service forecaster Jared Klein in northern Virginia
The weather service was forecasting possible snow for the New York and Boston areas, starting Sunday and continuing into Sunday night, with overnight temperatures in the 20s and wind gusts up to 30 mph.
The weather did not cause big problems for the airlines Friday, but Delta Air Lines spokesman Morgan Durrant said 500 weather-related flight cancellations were planned for Saturday nationwide. That included 300 of the 800 scheduled departures from the Atlanta hub. Durrant said those affected had been notified.
He recommended that passengers not travel by air in the Southeast on Christmas if they can help it.
"Atlanta will see more cancellations (Saturday) than on Sunday," he said. The Mid-Atlantic region could see cancellations Sunday.
Air Tran spokeswoman Judy Graham-Weaver said Friday evening that the carrier had only canceled two Saturday flights and was taking a wait-and-see approach to the storm.
Both airlines encouraged passengers to monitor their websites, and both offered to waive ticket-change fees for some flights scheduled for this weekend in the South and Mid-Atlantic.
In southern states, many were waiting to see whether they would enjoy a rare white Christmas.
By late Friday night, 2 to 3 inches of snow had fallen over several hours in Paducah, Ky. in the southwest part of the state, according to National Weather Service forecaster Jayson Wilson. "It's well above normal," he said.
Kentucky road crews were to load up with salt after 6 p.m. Friday for the anticipated snow in and around Louisville. Interstates and some roadways were pretreated with brine on Thursday.
Louisville last had snowfall on Christmas in 2002, when a half-inch fell.
The Weather Service said that for the first Christmas in 17 years, Nashville and Atlanta could get more than just a dusting of snow. The last time there was measurable snowfall on Christmas Day in Atlanta was in 1881, when 1.6 inches of snow fell on the city.
In the Atlanta suburb of Decatur, Vincenzo Tortorici said the prospect of snow evoked the memory of childhood Christmas visits to his relatives in Ohio.
"Snow was like frozen white icing on the cake of a magical time of my childhood," he said Friday. "I'm glad the weather might cooperate to give my own son a white Christmas this year."
In parts of Tennessee, Georgia and the Carolinas, the overnight snow was likely to be mixed with sleet and rain before turning entirely to snow. Temperatures in Georgia are expected to dip into the 20s on Christmas night, possibly leading to slick road conditions.
"If roads aren't able to dry up during the day, that's what will freeze up Saturday night into Sunday morning," said the weather service's Vaughn Smith in Atlanta.
Lon Anderson, a spokesman for AAA Mid-Atlantic, said people traveling by car on the East Coast over the holidays should check the weather forecasts.
"The fact is Mother Nature is going to be a big factor" in holiday travel, he said. "She's calling the shots this holiday season and in many places it will be very tough going." He said motorists should make sure their car is ready, especially their tires, and that they have enough windshield wiper fluid.
"It doesn't take much in the Mid-Atlantic area to cause mayhem," Anderson said.
In Minnesota, the storm brought 6 inches of snow Friday to Minneapolis and St. Paul. It pushed the monthly total there to 33.4 inches, topping the previous December record set in 1969.
The snow made traveling tough Friday in northeastern Iowa, where the bulk of the storm hovered. Cedar Rapids received more than 7 inches of snow.
Scott and Lori Whiting left Chicago for Colorado Springs, Colo., with their nine children Thursday evening. By morning, they had only reached Des Moines, a trip that normally takes about four hours, Lori Whiting said.
"The cars are really sliding around up there," Lori Whiting said. "It's kind of slushy. Some parts it's packed, and you don't think it's going to be slick and all of a sudden your car is fishtailing."
Scott Whiting got into a fender bender at a Des Moines truck stop. Still, the family was in good spirits and the children were singing carols.
Lori Whiting said they were hoping to make it to Colorado Springs for Christmas Eve.
"Depending on the number of potty breaks, you understand," she said.
Travelers could see airport screeners taking a closer look at empty insulated beverage containers like thermoses because air carriers were alerted about a potential terror tactic involving them, an administration official said.
The official, who spoke Thursday on condition of anonymity to discuss sensitive security matters, stressed that there is no intelligence about an active terror plot. The Homeland Security Department regularly alerts law enforcement about evolving terror tactics.
The Air Transport Association was expecting 44.3 million people on U.S. flights between Dec. 16 and Jan. 5 - up 3 percent over the same period a year ago but still below pre-recession travel volume. The average ticket price was $421, up by 5 percent.
The AAA predicted overall holiday travel to rise about 3 percent this year, with more than 92 million people planning to go more than 50 miles by Jan. 2. More than 90 percent said they would be driving.
Said Anderson of the storm: "The timing is really bad."
Contributing to this report were Associated Press writers Karen Hawkins in Chicago; Warren Levinson and Verena Dobnik in New York City; David Goodman in Detroit; Eileen Sullivan and Samantha Bomkamp in Washington; Michelle Price in Phoenix; Dylan Lovan in Louisville, Leonard Pallats and Greg Bluestein in Atlanta and Mark Pratt in Boston.