* Windward Side: When moist air from the ocean encounters a mountain range, it is forced to rise. As the air rises, it cools, and the water vapor condenses, forming clouds and precipitation on the windward side of the mountain.

* Leeward Side: The air that passes over the mountain is now dry because much of its moisture has been released as rain. This dry air descends on the leeward side, warming and becoming even drier, creating a rain shadow where there is very little rainfall.

In summary, the leeward side of a mountain receives less rainfall due to the rain shadow effect.