"Now the fun begins!" said a National Weather Service advisory from the forecast office in Mt. Holly, N.J. The center of the storm, said forecasters, was likely to reach the coast of North Carolina on Saturday morning, but after that, computer models disagreed on how close it would stay to land.
"Low pressure tracks to near Cape Hatteras Saturday morning, then deepens as it tracks to the northeast over the Atlantic Saturday night," said the Weather Service office for the New York City area. "The intense low will produce a swath of heavy snowfall...as well as a corridor of high winds. Once again...a track difference of only 100 miles will have a significant impact on the weather across the region."
Generally, snowfall in the northeastern U.S. can be expected to be heaviest along the coastline, said forecasters.
Next week, a second storm could bring a white Christmas to much of the country -- in a wide arc that could stretch from the Rockies to the mid-South to New England.
"A new surge of cold air will press southward later this weekend and lay the groundwork for snow, ice and rain over a large swath of the nation during Christmas week," said AccuWeather's Alex Sosnowski.
But the short-term forecast was of more concern. "I guess it's a good thing it's happening on a weekend," said a forecaster.
Additional information from ABC News' Lisa Stark. The Associated Press also contributed to this report.