Question

why patna get more rainfall than delhi

Answer 1

North eastern India receives abundant rainfall from South West Monsoon winds because of the presence of hills and mountains int he region. There is a decrease in rainfall as one goes from east to west. So Kolkata receives heavier rainfall than Patna and Patna receives heavier rainfall than Delhi. It is because as winds go from east to west they start loosing their moisture. So places in  the east get more rainfall than te places located in the west. Patna is located to the east of Delhi.