The rain-shadow effect is a common geographical phenomenon that occurs when mountain ranges block moisture-laden winds.
For the Western Ghats in India:
Moisture-laden monsoon winds from the Arabian Sea approach the Western Ghats from the west.
As these winds encounter the mountains, they're forced to rise, causing them to cool and condense, resulting in heavy rainfall on the western (windward) slopes of the Ghats.
After crossing the mountain range, the now-dry air descends on the eastern side.
As it descends, it warms up due to compression, which further reduces relative humidity and prevents rainfall.
This creates a "rain shadow" - an area of significantly reduced precipitation - on the eastern side of the Western Ghats, affecting regions of interior Karnataka, interior Tamil Nadu, and parts of Andhra Pradesh.
