Question

Which one of the following causes is responsible for rainfall during winters in the northwestern part of India?
1. Retreating depression
2. Cyclonic depression
3. Western disturbances
4. South-West Monsoon

Answer 1

Correct Answer - Option 3 : Western disturbances

The correct answer is Western disturbances.

• Western Disturbances are responsible for the rainfall during winter over the northwestern part of India.
• The Western Disturbance originates in the mid-latitude region near Europe and the Atlantic Ocean.
  • The low pressure builds up over the Mediterranean Sea and moves over Iraq, Afghanistan, and Pakistan before entering India, and contains substantial amounts of moisture.
  • When these low-pressure systems reach the Indian subcontinent, they are blocked by the Himalayas and rain as snow over the northwestern plains and the higher reaches of the western Himalayas.
  • After precipitation over northwest India, they weaken and are devoid of moisture, they blow as dry winds that form dense fog over the northern plains of India.

• The period June to September is referred to as the Southwest Monsoon period.
  • Southwest Monsoon period is the principal rainy season for the Indian subcontinent.
  • This is the summer monsoon period where the southwest monsoon holds away over the country.
  • The whole country receives nearly 75% of its rainfall during this period.