2009–10 North American winter

The 2009–10 North American winter saw several major blizzards affect the Northeastern United States. It refers to winter as it occurred across the North American continent from late 2009 to early 2010. While there is no well-agreed-upon date used to indicate the start of winter in the Northern Hemisphere, there are two definitions of winter which may be used. Based on the astronomical definition, winter begins at the winter solstice, which in 2009 occurred on December 21, and ends at the March equinox, which in 2010 occurred on March 20. Based on the meteorological definition, the first day of winter is December 1 and the last day February 28. Both definitions involve a period of approximately three months, with some variability.