The area behind a mountain with little rain is called a rain shadow.

Here's why:

* Orographic Lift: When moist air encounters a mountain range, it is forced to rise. As air rises, it cools, causing water vapor to condense and form clouds. This leads to precipitation on the windward side of the mountain.

* Descending Air: The air that has already released its moisture descends on the leeward side of the mountain. As it descends, it warms and becomes drier, creating a dry area known as the rain shadow.

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