The southwest Monsoon brings rains towards the end of summer as the high pressure built in the Indian Ocean pushes the wind masses towards the low pressure formed  on land. The southwestern summer Monsoons occur from July through September. Northern and central Indian subcontinent heats up during the hot summers. This causes a low pressure area over the northern and central Indian subcontinent. To fill this void, the moisture-laden winds from the Indian Ocean rush in to the subcontinent. These winds, rich in moisture, are drawn towards the Himalayas. The Himalayas act like a high wall, blocking the winds from passing into Central Asia and forcing them to rise. As the clouds rise their temperature drops and precipitation occurs.