India Records 40% Monsoon Deficit in June Due to El Niño Disruptions

The India Meteorological Department (IMD) has reported that the first leg of the South-West Monsoon in June 2026 recorded a 40% deficit in rainfall. The slow progress and weak intensity of the monsoon have been linked to El Niño conditions in the equatorial Pacific, raising concerns for the agricultural sector.

1. The ENSO Cycle: El Niño vs. La Niña

The El Niño-Southern Oscillation (ENSO) is a climate pattern in the tropical Pacific Ocean that influences global weather. It consists of three phases:

• El Niño: Characterized by the warming of sea surface temperatures in the central and eastern tropical Pacific. This weakens the atmospheric Walker Circulation and the trade winds, causing warm water to shift eastward. This shift typically suppresses rainfall over the Indian subcontinent, leading to weaker monsoons.
• La Niña: The opposite phase, characterized by cooler-than-average sea surface temperatures in the central and eastern Pacific. This strengthens the trade winds, pushing warm water westward and typically enhancing monsoon rainfall over India.
• Neutral Phase: Occurs when sea surface temperatures are close to long-term averages.

2. The South-West Monsoon Mechanism

The South-West Monsoon is driven by the differential heating of land and water. During summer, the landmass of Central Asia and India heats up rapidly, creating a low-pressure zone. Meanwhile, a high-pressure zone forms over the cooler southern Indian Ocean (near the Mascarene Islands). This pressure gradient drives moisture-laden winds across the equator toward India. These winds split into two branches: the Arabian Sea Branch and the Bay of Bengal Branch, bringing seasonal rains to the country.

3. Agricultural and Economic Implications

The South-West monsoon accounts for nearly 70-80% of India's annual rainfall. It is critical for the **Kharif season** (crops sown in June-July and harvested in September-October, such as rice, maize, cotton, and soybean). A significant rainfall deficit in June delays sowing operations, reduces reservoir storage levels, and increases dependency on groundwater, affecting crop yields and rural incomes.