Banana Belt

A banana belt is any segment of a larger geographic region that enjoys warmer weather conditions than the region as a whole, especially in the wintertime. The term "banana belt" is broad enough that it can be used to describe everything from the entire Antarctic Peninsula, to the southern part of American midwest states, to microclimate areas of mountain ranges.

Banana belts of the latter type may form on the lee sides of mountain slopes caused by orographic lift. When air rises over the top of a mountain range, it cools and releases moisture on the windward slope. As the air is pulled down the other side, it is compressed and heated via adiabatic heating, and it warms and dries territory in the mountain's rain shadow.

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