Monsoon

Monsoon, wind system in which the prevailing wind direction reverses in the course of the seasons, occurring where large temperature (hence pressure) differences arise between oceans and large land masses. Best known is that of Southeast Asia. In summer, moist winds, with associated hurricanes, blow from the Indian Ocean into the low-pressure region of northwestern India caused by intense heating of the land. In winter, cold, dry winds sweep south from the high-pressure region of southern Siberia.