Scores of flights were grounded as a storm out of the Midwest moved toward New York City, threatening to drop as much as 5 inches of snow starting at the morning commuter rush.
New York's five boroughs, as well as northern New Jersey and the lower Hudson Valley, are expected to get more than 2 inches during the day, according to a winter weather advisory issued by the National Weather Service.
"Snow develops toward the beginning of the Tuesday morning rush hour becoming moderate to locally heavy at times toward the end of rush hour," said the agency.
The advisory, meaning snow may make travel difficult, extends from Pennsylvania to Maine's eastern coast.
As of 4 p.m. Monday, 105 flights scheduled for Tuesday had been canceled at Newark Liberty International Airport in New Jersey, according to FlightAware, a Houston-based airline tracking service.
The snowfall will be the region's third in a week. More than 1,031 flights across the U.S. were canceled because of wintery weather over the weekend, FlightAware said.
Outside of New York, the storm is expected to bring as much as 4 inches of fluffy snow to eastern Pennsylvania and southern New Jersey, including Philadelphia and Trenton, according to the weather service.
Snow will spread into eastern New England around noon, said Tom Kines, a meteorologist with AccuWeather Inc. in State College, Pennsylvania. While the weather service predicted Boston will get 2 to 4 inches, Kines said he believes the city will received as much as 6 inches.
"As the system gets closer to the coast, it will be able to draw in some Atlantic moisture," Kines said.
The storm won't be a problem for Washington or Baltimore, he said.
After it passes, temperatures along the East Coast may moderate, Kines said.
"It is going to get mild in the second half of the work week," Kines said. "Any precipitation that falls later in the week will be primarily rain."
A total of 48.4 percent of the contiguous U.S. was covered by snow yesterday, with an average depth of 3.6 inches, according to the National Operational Hydrologic Remote Sensing Center in Chanhassen, Minnesota.