All this wet air is pulled in by a high pressure area over the Indian Ocean and a low pressure area to the south.
And, the southward moved axis of monsoon trough today passes through Bikaner, Deesa, Jabalpur, Raipur, Center of low pressure area.
They generally arise when a continuous pressure differential allows blood to flow constantly from a high to a low pressure area, as may occur in a variety of congenital defects, most commonly patent ductus arteriosus, anomalous origin of the left coronary artery, or coronary arteriovenous fistula.
Thus, air ordinarily moves from cooler places to warmer places, and winds blow from high pressure areas to low pressure areas.
