Question

why does the rainfall decrease from the east to the west in northern India
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Answer 1

$\huge\mathrm{Answer}$

Because the Western disturbances carry a lot of moisture and shared their rainfall in the North Eastern part of India . when it reaches the west its intensity of moisture decreases and thus the West Northern receives less rainfall than the East Northern

Answer 2

Answer: The amount of rainfall decreases from east to west in Northern India because of the progressive decrease in the humidity of the winds. As the moisture-bearing winds of the Bay of Bengal branch of the southwest monsoon move further and further inland, they exhaust most of the moisture they carry along with them.