<P> The influence of the Southwest Monsoon is felt as far north as in China's Xinjiang . It is estimated that about 70% of all precipitation in the central part of the Tian Shan Mountains falls during the three summer months, when the region is under the monsoon influence; about 70% of that is directly of "cyclonic" (i.e., monsoon - driven) origin (as opposed to "local convection"). </P> <P> Around September, with the sun fast retreating south, the northern land mass of the Indian subcontinent begins to cool off rapidly . With this air pressure begins to build over northern India, the Indian Ocean and its surrounding atmosphere still holds its heat . This causes the cold wind to sweep down from the Himalayas and Indo - Gangetic Plain towards the vast spans of the Indian Ocean south of the Deccan peninsula . This is known as the Northeast Monsoon or Retreating Monsoon . </P> <P> While traveling towards the Indian Ocean, the dry cold wind picks up some moisture from the Bay of Bengal and pours it over peninsular India and parts of Sri Lanka . Cities like Madras, which get less rain from the Southwest Monsoon, receives rain from this Monsoon . About 50% to 60% of the rain received by the state of Tamil Nadu is from the Northeast Monsoon . In Southern Asia, the northeastern monsoons take place from December to early March when the surface high - pressure system is strongest . The jet stream in this region splits into the southern subtropical jet and the polar jet . The subtropical flow directs northeasterly winds to blow across southern Asia, creating dry air streams which produce clear skies over India . Meanwhile, a low pressure system develops over South - East Asia and Australasia and winds are directed toward Australia known as a monsoon trough . </P> <P> The East Asian monsoon affects large parts of Indochina, Philippines, China, Korea and Japan . It is characterised by a warm, rainy summer monsoon and a cold, dry winter monsoon . The rain occurs in a concentrated belt that stretches east - west except in East China where it is tilted east - northeast over Korea and Japan . The seasonal rain is known as Meiyu in China, Changma in Korea, and Bai - u in Japan, with the latter two resembling frontal rain . The onset of the summer monsoon is marked by a period of premonsoonal rain over South China and Taiwan in early May . From May through August, the summer monsoon shifts through a series of dry and rainy phases as the rain belt moves northward, beginning over Indochina and the South China Sea (May), to the Yangtze River Basin and Japan (June) and finally to North China and Korea (July). When the monsoon ends in August, the rain belt moves back to South China . </P>

Which country in south asia averages the greatest amount of rainfall