Why do the Western Ghats receive heavy rainfall in Keralam?

The Western Ghats in Keralam receive heavy rainfall primarily due to the phenomenon of orographic precipitation.

As moisture-laden winds from the Arabian Sea—specifically those associated with the southwest monsoon—approach the coast, they encounter the steep, seaward slopes of the Western Ghats. The mountain range acts as a physical barrier, forcing the air to rise abruptly. As this air ascends, it cools, losing its capacity to hold moisture and resulting in heavy rainfall on the windward side of the highlands.1234

This process is highly effective in Keralam, where the mountains intercept the monsoon winds, leading to significant annual precipitation that can exceed 200 inches (5,000 mm) in some elevated areas. Conversely, this mechanism creates a rain shadow effect on the leeward side of the range, where the descending air is much drier.324