Question

why the most parts of the country receive rainfall from June to September but some parts like the Tamil Nadu coast it's a large portion of its rain during October and November please explain why this happen

Answer 1

In winter air over Siberia cools down and sinks causing a high pressure area north of the Himalayas. This in turn create winds that blow across India towards the Indian ocean . This wind system is known as north-east monsoon which is responsible for most of the rainfall in Tamil Nadu .

India is affected by southwest monsoon (July to September) and Northeast monsoon (October to December ). During southwest monsoon entire India receives rainfall except Tamil Nadu . As TN has to be in the rain shadow area(its on the leeward side of the Western Ghats which obstructs the southwest monsoon) there is very little precipitation during thus period.

On the other hand it gets rainfall during northeast monsoon winds which originates as dry winds and picks up a lot of moisture along its way through the Bay of Bengal and strike the eastern coast of TN which is the only coastern region along its path towards Sri Lanka .

That's it!! Phewww