Highest Rainfall in India: Mawsynram is a village in the East Khasi Hills district of Meghalaya state in north-eastern India, 56 kilometers from Shillong. It is reportedly the wettest place on Earth, with an annual rainfall of 11,872 millimetres (467.4 in). According to the Guinness Book of World Records Mawsynram received 26,000 millimetres (1,000 in) of rainfall in 1985. Mawsynram, located about 15 km north-west of Cherrapunji in the state of Meghalaya (India) appears to be the wettest place in the world or the place with the highest average annual rainfall
Three reasons for high rainfall at Mawsynram:
1. The warm moist winds of the northward-moving air from the Bay of Bengal during the monsoon, which cover an extensive area but are forced to converge into the narrower zone over the Khasi Hills, thus concentrating their moisture.
2. The alignment of the Khasi Hills (east to west) places them directly in the path of the airflow from the Bay of Bengal, producing a significant uplift (plus cooling, further condensation and thus more rain).
3. Finally, uplift over the Khasi Hills is virtually continuous in the monsoon period because the lifted air is constantly being pulled up by vigorous winds in the upper atmosphere, hence the rainfall is more or less continuous.