BOSTON (AP) - Some schools stayed closed Monday morning and airlines struggled to catch up as the Northeast plowed out after the powerful weekend snowstorm that piled snow nearly 4 feet deep in places.

"It's not unique but it is unusual that we would have a December snowstorm that would yield this amount of snow," said National Weather Service meteorologist Charlie Foley.

Thirteen deaths were linked to the storm.

A few snow flurries lingered in northern Maine on Monday morning but the storm, which started blowing up the Eastern Seaboard on Friday, had moved out into the Atlanta east of Nova Scotia, the National Weather Service said.

Connecticut schools opened a little late, and high school sports organizers worked to reschedule six football championships that were postponed over the weekend.

The deepest snow, 47 inches, was recorded in Pinkham Notch at Mount Washington in New Hampshire. Some other parts of New England were blanketed by nearly 3 feet, with western Maine and the North Shore of Massachusetts particularly buried. Up to 2 feet fell in eastern New York, and Cliffside Park, N.J., had almost as much, 23 inches.

Ten high school students and two adults were missing on a weekend hiking and camping trip in western Maine. A Maine game warden pilot searched from the air Monday morning for the hikers, who left Friday and were due back Sunday.

In some places, snow fell for more than 36 hours.

In addition to snow, flooding was a problem in some coastal areas where the storm's high wind drove waves onto shore and over seawalls. Water was a few feet deep on some streets in Scituate, Mass., said fire Capt. George Anderson.

One rescue was needed Sunday in Scituate. "We had people stranded in a car," Anderson said. "The water on the street was two or three feet deep."

As the snow melted, some other areas were warned of a chance of light flooding because of poor drainage and snow-clogged sewers.

Lines were long at Boston's Logan International Airport, which was still operating with one runway Monday morning instead of its usual two. Airport spokesman Phil Orlandella said officials hoped to open the second runway by midday.

There were no more delays Monday at the New York City area's Kennedy, La Guard and Newark airports, but flights from La Guardia to Boston were canceled because of Logan's problems, said Dan Maynard, a spokesman for the Port Authority of New York and New Jersey.

During the weekend, hundreds of flights had to be canceled at Logan, Philadelphia, Kennedy, La Guardia and Newark airports.

Cleaning the roads had taken a huge expenditure in money and man hours.

Early Sunday, when the storm peaked in Massachusetts, about 3,300 plows and other equipment were out on the state's highways, said Jon Carlisle, spokesman for MassHighway. The cost to the state wasn't immediately calculated, but Boston Mayor Thomas Menino estimated removal costs in the city at $3 million.

New Jersey used more than 70,000 tons of salt and sand statewide on its roads, said Anna Farneski, spokeswoman for the state Department of Transportation.

The storm was blamed for three traffic deaths in New Jersey, two each in Vermont and Virginia, and one each in Pennsylvania, Connecticut and upstate New York. One man died in a sledding accident in Rhode Island, and New Jersey and Rhode Island each reported one person dead after collapsing while shoveling snow.

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