orographic lifting

Orographic lifting occurs when moist air is forced to ascend over a mountain or elevated terrain. As the air rises, it cools, causing moisture to condense into clouds and often leading to precipitation on the windward side of the mountain. Once past the peak, the drier air descends on the leeward side, warming and drying out, which often results in a rain shadow—a dry area. This process explains why mountains influence local weather patterns and why regions near mountains can be significantly wetter on one side and drier on the other.