Climatic Regions of the United States, Humid Continental Climates
The eastern part of the United States includes two climate types: Humid Continental and Subtropical. Humid Continental is the largest climate type in the United States. It has two subtypes: those areas with hot summers and those with warm summers. The Humid Continental climates are transitional climates between the severe Subarctic climate region in Canada and the warmer Humid Subtropical region of the southern and southeastern United States. These climates are battlegrounds between cold polar air masses surging southward and tropical air moving northward. Humid Continental climates have four distinct seasons and large variations in temperature. They are warm in summer and cold enough to sustain winter snow for some months.
These climate zones were similar to the climates of Europe and allowed European settlers to continue farming as they had in their homelands. They established family farms and concentrated on raising crops and using some of the produce to feed the farm's livestock. Eventually, this system of general crop and livestock farming spread westward across the United States.