Nor’easter had right mix
Altitude, differences of air masses key to snowfall variations
The October nor’easter that dumped more than two feet of snow on parts of Massachusetts was not only unusually early, but it was also striking for the large variation in the snowfall amounts around the state. The storm was the result of the collision of two air masses - cold air coming from Canada and humid, warm air moving up the coast. The storm buried some communities in snow and soaked others with rain primarily because of variations in temperature due to slight changes in altitude.