The correct answer is Western Disturbance. Explanation & Key Takeaways: • Western disturbances originate from the Mediterranean Sea, Black Sea, and Atlantic Ocean and reach the northwestern regions of India through westerly winds. • They cause rain and snowfall mainly in the winter season in North India and Pakistan. They are very important for Rabi crops like wheat. • Western disturbances cause heavy snowfall in the hilly areas and winter rainfall in the plains, which affects the normal winter season. • Western disturbances are not a part of the monsoon. It is a non-monsoon system which remains active in the winter season in India. Related Concepts: Arabian Sea Branch: • This is the main branch of the South-West monsoon. • It carries moisture from the warm winds of the Arabian Sea and causes heavy rainfall on the western coast of India. • The monsoon enters the Kerala coast through this branch. • It emerges on the Western Ghats and brings most of the rain. • The Arabian Sea branch reaches Maharashtra, Gujarat, Rajasthan and Punjab. • This branch causes heavy rainfall on the western coast. Rainfall gap: • The reduction in rainfall during the monsoon is called the rain gap. • It is also called a break in monsoon. • It generally occurs between June to September. • This phenomenon occurs when the monsoon winds become weak. • During this period, there may be drought in some parts of the country and heavy rainfall in some parts. • The duration of the rain gap may range from a few days to a few weeks. Cloud burst: • The phenomenon of sudden and excessive rainfall is called cloudburst. • In this, a huge amount of water falls in a very short period of time. • This phenomenon occurs mostly in hilly areas. • Cloudbursts can cause floods and landslides. • It is caused by the sudden meeting of hot air and cold air. • Cloudburst is common during monsoon and in low-pressure areas.