The Himalayas
The Himalayas play a significant role in preventing the southwest monsoon winds from escaping from India. Here's how:

Barrier to Wind Flow:
- The Himalayas act as a physical barrier to the southwest monsoon winds, which blow from the Arabian Sea towards the Indian subcontinent during the summer months.
- As the winds approach the Himalayas, they encounter the massive mountain range, which obstructs their path and forces them to rise upwards.
- This upward movement of the winds leads to the formation of a temporary high-pressure cell over the Himalayan region, known as the Tibetan High. This high-pressure system acts as a barrier to the winds, preventing their escape.

Diverting Wind Flow:
- The Himalayas not only block the direct passage of the monsoon winds but also divert their flow.
- When the winds encounter the Himalayas, they are forced to split into two branches: the Arabian Sea branch and the Bay of Bengal branch.
- The Arabian Sea branch moves towards the northwest, affecting the western parts of India, while the Bay of Bengal branch moves towards the northeast, influencing the eastern parts of the country.
- This diversion of wind flow ensures that most parts of India receive rainfall during the monsoon season.

Enhancing Precipitation:
- The Himalayas also contribute to increased precipitation in the Indian subcontinent.
- As the monsoon winds are forced to rise over the Himalayas, they cool down, leading to condensation and the formation of clouds.
- These clouds bring rainfall to the northern plains of India and the foothills of the Himalayas.
- The high altitude of the Himalayas also enhances orographic precipitation, where moist air is forced to rise and release moisture as it encounters the mountain slopes.

Conclusion:
In conclusion, the Himalayas act as a barrier to the southwest monsoon winds, preventing their escape from India. The mountain range diverts the wind flow, ensures widespread rainfall across the country, and enhances precipitation through orographic effects.