This seems to be not an easy question to answer.
For several years, a pair of towns just a few miles apart in the Khasi Hills of northeastern India has claimed the title, as each receives an average of more than 460 inches (nearly 40 feet) of rainfall every year. The town of Cherrapunji has long advertised itself as the “wettest place on planet Earth.” However, the neighboring village, Mawsynram, edges out Cherrapunji when it comes to average annual rainfall by less than 4 inches, according to the most recent reliable data.
Another serious contender to the title is Hawaii’s Mount Waialeale, which has an average of more than 450 inches of rainfall per year. In 1982, a record 683 inches of rain fell there, which works out to nearly 57 feet.
All of these “wettest” places however may turn out to be runners-up to Puerto Lopez de Micay, a small town near the coastline of western Colombia. Between April 1960 and February 2012, an average annual rainfall of just over 507 inches has been recorded at the weather observation station here, including an astonishing 937 inches of rain in 1984.