Konkan Coast faces On-Shore South West Monsoons during summer. The moist laden winds causeheavy rainfall (more than 300 cms). But these winds do not result in heavy rainfall on the Coromandel Coast lies of Western Ghats. Coromandel Coast also receives winter rainfall from North Eastern Monsoons, but on Konkan Coast these winds are off-shore and do not result in rainfall. Thus Coromandel Coast gets rainfall in both the seasons, but the total amount is less than that of Konkan Coast. Total rainfall in Chennai is about 128 cms, but it is 180 cms in Mumbai.

Tamil Nadu gets most of rain from North-Eastern Monsoons in October and November. These Winds after picking up moisture from Bay of Bengal fetch more rain on the eastern coast. This is why; Tamil Nadu receives rain in winter when the fury of monsoons is over in most parts of the country.