Some schools are closing in parts of Ohio, the mid-Atlantic, and the northeast as another winter storm heads toward the eastern United States one day after temperatures soared to between 10 and 15 degrees Celsius.The National Weather Service (NWS) said the storm could bring up to 20 centimeters of snow Monday to Philadelphia and New York City. Temperatures are returning to freezing.The snowstorm was making it difficult for some people to travel. About 1,000 airline flights were cancelled in cities including Philadelphia, Newark, and New York.Schools closed in Ohio, Pennsylvania, New Jersey, Delaware, and Connecticut ahead of the storm.