The ugly winter weather already blamed for at least seven deaths across the country continued Monday, bringing the first snow accumulations of the season to major cities such as Philadelphia and Boston and delaying millions of travelers.

The National Weather Service forecast heavy snow for the Northeast and freezing rain over the region through Tuesday, especially in the northernmost areas of New England. Fifty-three million people are facing winter weather alerts from West Virginia up thorough Maine.

Boston and coastal areas of Massachusetts were expected to get as much as 6 inches of snow, while areas farther inland could get up to 11 inches, with ice accumulations up to a tenth of an inch. The Philadelphia area could get as much as 5 inches, with up to a foot in areas of the southern Poconos and extreme northwest New Jersey.

New York City is expected to miss the worst of the storm, but a band of heavy snow could fall somewhere over the city near rush hour, which forecasters say will drop anywhere from three to six inches. Areas farther north could receive several more inches, forecasters said. Snow showers are supposed to end around 4 a.m. ET.

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While the stubborn system isn't as big as typical midwinter storms, the snow and ice were enough to put a big crimp on travel plans as families returned home from their Thanksgiving holidays.

Boston Logan International Airport reported that 124 arrivals and departures were canceled Sunday, along with 119 at Newark Liberty International Airport in New Jersey, 69 at Philadelphia International Airport and 31 at LaGuardia Airport in New York. Across the country, more than 3,000 flights were already canceled as of Monday afternoon, and nearly 13,000 were delayed, as the storms continue, according to the live flight tracking site Flight Aware.

At Buffalo-Niagara International Airport in New York, ice caused a Delta-owned Endeavor Air flight from LaGuardia to skid off the taxiway on arrival Sunday morning, airport officials said.

No injuries were reported among the 72 passengers and crew, Bill Major, the airport's fire chief, said. Twenty-five other arrivals and departures were canceled Sunday as rain iced up the runways during a fast drop in temperature, Major said.

"The weather and icing is an issue for the airfield," Major said. "It's one of the bigger challenges they have, because it's hard to keep up with."

Snow and ice both helped and hampered firefighters as they battled a fire at the Mid-Station Lodge at Whiteface Mountain in Wilmington, New York, near Burlington, Vermont, authorities said Saturday night.

No cause had immediately been determined for the fire, in which no one was injured, NBC affiliate WPTZ of Burlington reported.

Assistant Chief Cliff Holzer of the Wilmington Fire Department, told WPTZ that the location of the fire was difficult to reach. But he said crews were able to take advantage of equipment at the site, using the giant guns that help to create artificial snow for skiers to attack the fire.

Scott Christiansen, vice president of the Olympic Regional Development Authority, the state agency that manages the lodge, said the building was destroyed.

The nasty holiday-week weather also slammed the Midwest on Saturday and Sunday, burying Duluth, Minnesota, under 20 inches of snow, where big waves near Lake Superior are causing flooding and officials are closing roads as the tide rises.

The weather has also proved deadly, blamed for at least seven confirmed deaths across the country, and one in Canada.

The Missouri State Highway Patrol said three people were killed in two separate water-related incidents in heavily flooded Bollinger County, south of St. Louis, on Saturday.

Two boys, ages 5 and 8, drowned near Patton when the vehicle they were riding in was swept off a flooded road, the patrol said, and a Louisiana man was killed when his vehicle was swept into the Whitewater River.

Motorists navigate an intersection in Pittsfield, Massachusetts, in the early hours of a snowstorm that hit the region Sunday. Gillian Jones / AP

In Arizona, two children, both about 5 years old, were found dead Saturday after they were reported missing when a vehicle was swept up a creek in Tonto Basin, about 50 miles northeast of Phoenix, the sheriff's office said. Crews were still searching Sunday for a 6-year-old girl.

A 6-year-old boy died after he fell and struck his head when snow-removal equipment being driven by his father lurched in unincorporated Provo Canyon on Friday morning, the Utah County Sheriff's Office said. The boy's 9-year-old brother was unhurt in the incident, in which authorities said their father wasn't at fault.

In Canada, one person died in Ontario after the same storm caused a 30 car pile-up on a busy highway as the road conditions deteriorated.

And in South Dakota, a man was killed early Friday when he lost control of his pickup truck on an ice-covered road near Cavour, in Beadle County, the state highway patrol said. Two other people in the truck weren't seriously injured.

Near Chamberlain, South Dakota, in Brule County, investigators were also trying to determine to what extent the rough weather played a role in the crash of a single-engine turboprop plane shortly after takeoff Saturday.

Nine people, including two children, were killed, the Brule County state's attorney's office said. The area was under a winter storm warning, with a few inches of snow having accumulated, the National Weather Service said.

While no official cause for the crash had been determined, "definitely we'll be looking into the weather conditions," Peter Knudson, a spokesman for the National Transportation Safety Board, said.

An initial report isn't expected for about two weeks, Knudson said.