Monsoons are found not only in South Asia; they are part of a global-scale circulation that affects almost all tropical regions (e.g., Australian monsoon, African monsoon, etc.). One occurs in North America too, the North American monsoon, which affects western Mexico and the southwestern United States, in particular, Arizona and New Mexico.
Click here for original story, The formation of the North American Monsoon: A unique case in the world
Source: Phys.org