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The 2026 monsoon and El Niño

Prelims and Mains

LeadA dry monsoon under a strong El NiñoSeptember 2026

Why in news

The southwest monsoon ended on 30 September 2026 at 87 per cent of the long period average, the driest season in 11 years, and Maharashtra declared drought in 265 of its 358 talukas on 26 September.

87 per centof the long period average: 759.4 mm against 868.6 mm
13thdriest monsoon since 1901
282districts deficient, over 38 per cent of the country's area
265 of 358talukas of Maharashtra declared drought hit

Background

The long period average (LPA) is the average monsoon rainfall over 1971 to 2020, and a season counts as normal when it falls between 96 and 104 per cent of it.

El Niño is the abnormal warming of the surface waters of the equatorial Pacific, which suppresses Indian rainfall, while La Niña favours it.

El Niño is declared on the Niño 3.4 index, the sea surface temperature anomaly in the central and eastern equatorial Pacific, which stood at +2.51°C.

Why the season was uneven

Low pressure systems from the Bay of Bengal were active on 77 days against a normal 57, which kept central India wet despite El Niño.
The Madden Julian Oscillation (MJO), a band of rain bearing clouds with a period of 30 to 60 days, stayed unfavourable over the south, so every southern State ended in deficit.

Inside Maharashtra the deficit was 18 per cent, but Marathwada was 38 per cent short and Vidarbha 27 per cent, both rain shadow regions.

Drought and flood in the same season

Odisha ended with a 29 per cent excess, brought by 11 Bay of Bengal systems one after another, which left the soil saturated and turned each new spell into runoff.
A deep depression meeting a Western Disturbance flooded Uttar Pradesh in the last week of September, as the monsoon was withdrawing.

What lies ahead

The India Meteorological Department (IMD) projects El Niño effects until at least March 2027.
A strong El Niño generally favours a wetter northeast monsoon over the southern peninsula, though not in every such year.
Long duration arhar flowers in October and fills its pods in November, so a dry spell then causes terminal moisture stress, and low soil moisture may hold back rabi sowing.

The way forward

Build drainage for repeated intense downpours, since one day and five day rain bursts are becoming more common even as heavy rain days decline.
Act on the forecast in crop planning: short duration pulses, millets and oilseeds where the season is expected to fail.
Document the ecological effects of this El Niño, as 188 Indian scientists have asked, since a coral reef needs about a decade to recover from bleaching.

Prelims facts

The LPA is calculated over 1971 to 2020; normal is 96 to 104 per cent of it.
A Western Disturbance is an east moving extra tropical cyclone that gathers moisture from the Mediterranean, Black, Caspian and Arabian Seas and is carried by the subtropical westerly jet stream.
The Indian Ocean Dipole can dampen or amplify El Niño's effect on India.
The MJO moves with a period of 30 to 60 days.

Open the lead on its own page

El Niño is the warm phase of the equatorial Pacific and is usually, though not always, linked to a weaker Indian monsoon.

Events are graded weak, moderate, strong or very strong; neither the World Meteorological Organization nor the India Meteorological Department recognises a "Super El Niño" category.
The phase of the El Niño Southern Oscillation (ENSO) is set by the sea surface temperature anomaly over the Niño 3.4 region of the equatorial Pacific.
Above +0.5°C is El Niño and below −0.5°C is La Niña, and episodes usually peak in the northern winter.
A positive Indian Ocean Dipole can offset El Niño.
The Department has used a Multi Model Ensemble of coupled models for its seasonal forecast since 2021.

What changed

30 Sep 2026LeadA dry monsoon under a strong El Niño

cloudburst: Sudden very heavy rain, taken by the India Meteorological Department as more than 100 mm in an hour over a small area.

State Disaster Response Fund: The fund a State draws on for relief and reconstruction immediately after a notified disaster.

State Disaster Mitigation Fund: The fund for long term works that reduce disaster risk before a disaster, rather than relief after one.

Doppler shift: The shift in a wave's frequency when its source and observer move towards or away from each other; the radar reads it to find the wind inside a cloud.

weather modification: Deliberate intervention in the atmosphere, such as seeding clouds, to change how much rain falls.

Long period average: The average June to September rainfall over 1971 to 2020, 87 cm.

Uncompensable heat stress: A condition in which the body cannot cool itself by sweating because of extreme heat and humidity.

Regional Meteorological Centre: The IMD office that coordinates weather and climate services for a group of States.

Moisture adequacy index: An index of soil moisture used in assessing drought.

Trigger-1: The first alert stage of Maharashtra's Drought Management Code, based on rainfall deficiency and a dry spell of at least 21 days.

Panchnama: A field survey that records the condition of a crop.

Kallakadal: The name fishermen in Kerala give to a swell surge.

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