Monsoon winds change their direction because of the differences in the relief features , elevated areas, high mountains, hills, valleys, contours of land effects the wind direction.
The dominant air currents that affect climate are known as prevailing winds. ... For example, warm winds that travel over water tend to collect moisture as they travel; the water vapor in the air will condense as it moves into colder climates, which is why temperate coastal areas often receive heavy rainfall.