South West Monsoon Winds

Añadido: 2026-06-01

[00:00:02]In our last video, we learned about the main seasonal winds of India. The southwest winds, western disturbances and northeast winds. In this session, we will understand the southwest winds in detail. Before that we will first learn about the Tibetan plateau, Himalayas and the subtropical jetream which together play a major role in creating and controlling India's monsoon system.

[00:00:33]Later we will see the direction of the southwest winds and which states receive rainfall from these monsoon winds.

[00:00:46]First, let's understand the concept of winds flowing from a high pressure region to a low pressure region with a simple playground example. Imagine a playground that is already full of kids playing inside. Since it is not empty, the kids waiting outside cannot enter the playground.

[00:01:07]There is also a gatekeeper who has been told not to allow anyone inside until playing kids leave the playground.

[00:01:16]After some time when the kids inside leave the playground, the gatekeeper also leaves. Now empty space is created inside the playground and the waiting kids quickly rush into play. In the same way when the hot air rises up it creates an empty space below which is called low pressure and then the air moves from a high pressure region to a low pressure region to fill that empty space.

[00:01:48]Now in next few pages we will try to understand how the teamwork of the Tibetan plateau the subtropical jetream and the Himalayas brings the southwest monsoon into India. The Tibetan plateau acts like an engine or a powerful heater that pulls the southwest monsoon towards India. The subtropical jet stream acts like a gatekeeper until it moves away.

[00:02:16]The southwest monsoon cannot enter into India. The Himalayas act like a giant wall that blocks the monsoon winds to go away from India.

[00:02:34]The Tibetan plateau is like a huge flat mountain in the sky behind the Himalayas.

[00:02:41]The plateau goes through three different stages throughout the year.

[00:02:46]In winters, the Tibetan plateau is covered with ice and very cold. From April to May, it starts warming up slowly as the ice melts.

[00:02:58]By the end of May and in June, it becomes extremely hot. When the Tibetan plateau becomes very hot, the hot air above it starts moving upward like a hot air balloon. As the hot air rises, it leaves behind an empty space creating a low pressure area. Since the Tibetan plateau is already at a very high level, this rising air creates a giant empty space much higher in the sky like a huge suction engine pulling air towards it.

[00:03:35]And that how it helps in pulling the moisture southwest monsoon winds towards India.

[00:03:42]Do you know Tibetan plateau is so high that it is also called as roof of the world? It is around 4,000 m above sea level.

[00:04:01]The subtropical jetream acts like a gatekeeper in the sky. During winter and early summer, it blows over northern India from west to east and prevents the monsoon winds from entering. When summer becomes stronger, Tibetan plateau becomes very hot and strong enough to shift this jetream northwards away from India. Once this gatekeeper moves aside, the southwest monsoon gets a clear path to enter India.

[00:04:41]The Himalaya act like a giant wall. They stop the southwest monsoon winds from escaping towards central Asia. As the winds hit the Himalaya, they are forced to rise upward, cool down and release heavy rainfall over many parts of India.

[00:05:01]Without the Himalaya, much of the monsoon moisture would move away and India would receive far less rainfall.

[00:05:11]Similarly, the western guards help bring heavy rainfall to the western coastal regions of India by blocking the way of the southwest monsoon winds.

[00:05:23]This is also the reason few part of southern India do not receive much rainfall during this time.

[00:05:37]The southwest monsoon winds enter India from the Indian Ocean and split into two big branches.

[00:05:45]One branch travels along the Arabian Sea and the western coast while the other moves through the Bay of Bengal towards northeast India. These winds bring heavy rain to many parts of India.

[00:06:06]The Arabian sea branch of the southwest monsoon first hits the western Gads on India's west coast. The mountain forced the winds to rise higher causing heavy rain in coastal places like Kerala, coastal Karnatak, Goa, coastal Maharashtra. Southern regions which are on the eastern side of these gads receive much less rain because the mountains block many of the rain clouds.

[00:06:44]A part of the winds of Arabian sea branch travel further and hit the Himalayas rise up and bring heavy rain in northern and central Indian places like Punjab, Hana, Himachal Pradesh, Uttar Pradesh, Uttarakand, Madhya Pradesh, Chhattisgarh, Gujarat and some parts of Rajasthan.

[00:07:18]The Bay of Blingol branch travels along India's east coast and moves towards northeast India. These winds bring very heavy rain to the northeast states.

[00:07:31]After that the winds turn westward and spread rain across many parts of central and northern India. This brings rains heavily in Assam, Meghal, Nagaland, Manipur, Mizoram, Tripura, Arunachal Pradesh and then rains in Odisha, West Bengal, Jharkand, Bihar, Uttar Pradesh and many other states.

[00:08:07]So we have seen how the Tibetan plateau heats up and pulls the winds. The subtropical jet stream is the gatekeeper and stops the winds to enter until plateau turns into a powerful suction engine and drifts away the jet. We have also seen how Himalayas and western guards stop the winds to move further away and bring rain to many parts of India. How the southwest monsoon divides into two branches and moves further.

[00:08:47]Do you know how the eastern coast which received much less rain because of the western guards now gets its much needed rain? Think about it until we meet again to discover the answer together. Stay tuned.