Indian Monsoon In Global Warming Era: Lessons And Warnings From A Possible Super El Niño

As the southwest monsoon advances across India each year, millions of farmers look to the sky with expectation. The first showers influence sowing decisions, reservoir storage, groundwater recharge, hydropower generation and rural livelihoods. In India, the monsoon is not merely a weather system; it is the foundation of agriculture, water security and economic resilience.

India’s dependence on this monsoonal system is exceptional. The southwest monsoon, active from June to September, contributes nearly 80% of India’s annual rainfall and supports the Kharif cropping season.

People quench their thirst at a tap at the Sangam area on a hot summer day in Prayagraj (ANI)

The northeast monsoon, from October to December, is also crucial for Tamil Nadu, southern Andhra Pradesh and parts of Rayalaseema. This rainfall supports agriculture, replenishes rivers and reservoirs, recharges groundwater, sustains hydroelectric power generation, and influences food prices and economic growth. Thus, India’s monsoon is not a single rainfall spell, but a complex seasonal water cycle that supports more than a billion people.

Scientifically, the monsoon is driven by the seasonal reversal of winds caused by differential heating between land and ocean. During summer, the Indian landmass heats faster than the surrounding seas, creating a broad low-pressure region that draws moisture-laden winds from the Arabian Sea and the Bay of Bengal. These winds are organized by the low-level jet, the monsoon trough and the thermal influence of the Tibetan Plateau, together sustaining one of the most powerful rainfall systems on Earth.

Although monsoon systems occur in several regions of the world, including Africa, Australia, and East Asia, the Indian monsoon is among the most powerful and influential. Nearly half of the world's population lives in monsoon-dependent regions, but few countries depend on monsoon rainfall as much as India.

Harvested wheat is being checked by a farmer under scorching conditions in Samba (ANI)

Why the 2026 monsoon needs close attention

This year, discussions about the monsoon have become even more important because climate scientists are closely monitoring the possibility of a strong El Niño event developing during 2026. El Niño is related to increases in the likelihood of above- and below-average precipitation over many regions of the globe. Historically, El Niño years have often been associated with weaker monsoon rainfall over India.

Understandably, many farmers, and policymakers are asking a simple question: Will the monsoon continue to support India in a warming climate?

Timing of wet and dry conditions related to El Niño (Source: Climate Hazards Center, United States of America)

The 2026 monsoon should be viewed not only as a seasonal forecast issue, but also as a climate-risk warning for agriculture, water management and disaster preparedness.

The India Meteorological Department’s updated Long-Range Forecast (LRF) indicates that June-September 2026 rainfall over India is likely to be below normal, around 90% of the Long Period Average (LPA), with a model error of +/-4%. Since the current all-India seasonal monsoon LPA is 87 cm, this implies rainfall of roughly 78 cm, about 9 cm below the long-term normal.

The probability signal is equally important. IMD estimates an 84% probability of below normal or deficient rainfall over the country as a whole. The Monsoon Core Zone, which covers many rainfed agricultural areas, is also likely to receive below-normal rainfall. Northwest India, Central India and South Peninsular India appear more vulnerable, while parts of Northeast India and eastern peninsular India have a relatively better chance of normal to above-normal rainfall.

Infograpbhics for Indian Monsoon (ETV Bharat)

El Niño risk: Preparedness, Not Panic

A developing El Niño adds to this concern. El Niño is marked by abnormal warming of the central and eastern equatorial Pacific Ocean and is often associated with a weaker Indian summer monsoon. IMD has indicated that ENSO conditions are moving toward El Niño during the monsoon season, while the Indian Ocean Dipole is likely to remain neutral. A neutral IOD may limit the possibility of offsetting El Niño’s suppressing influence on monsoon rainfall.

International ENSO outlooks also point to a high probability of El Niño conditions in 2026, with the possibility of further strengthening later in the year. However, El Niño should not be interpreted as an automatic drought warning. Indian monsoon rainfall is shaped by several interacting systems, including Indian Ocean temperatures, monsoon depressions, land-surface heating, snow cover, the Madden-Julian Oscillation and regional circulation patterns. Some El Niño years have produced severe rainfall deficits, while others have shown mixed regional impacts. The practical message is therefore preparedness, not panic.

How the 2026 monsoon is evolving

The current season has already shown a spatially uneven evolution. IMD declared the onset of the southwest monsoon over Kerala on 4 June 2026, slightly later than the normal date of 1 June. During 1-10 June, all-India monsoon rainfall was 26% below normal, with larger deficits over East and Northeast India (-39%) and Central India (-45%). In contrast, South Peninsular India was close to normal to slightly above normal (+3%). This pattern shows that the early-season concern is not a failed monsoon, but a slow and uneven advance with weak rainfall over several agriculturally important regions.

The southwest monsoon normally advances in surges and covers the entire country by around mid-July.

Infograpbhics for Indian Monsoon (ETV Bharat)

Therefore, early June deficits should be monitored carefully, but they should not be interpreted as the final seasonal outcome. A recovery during late June and July remains possible if monsoon circulation strengthens. However, emerging El Niño conditions, changing large-scale circulation and intermittent weather disturbances may enhance intraseasonal variability during the season.

The main risk in 2026 is therefore not only the seasonal rainfall total, but also the timing, distribution and intensity of rainfall. Longer dry spells may be interrupted by short, intense rainfall episodes, increasing the risk of flash floods, urban flooding and crop stress even if seasonal rainfall eventually approaches normal levels. For Telangana, Rayalaseema and Coastal Andhra Pradesh, this uneven rainfall distribution is especially important because sowing, reservoir inflows and groundwater recharge depend strongly on the timing of rainfall.

Looking ahead, if El Niño persists into the post-monsoon season, the Northeast Monsoon during October-December over southeast India, particularly Tamil Nadu, Rayalaseema and Coastal Andhra Pradesh, may become more active. Historical studies show that El Niño years often favour normal to above-normal northeast monsoon rainfall over southern peninsular India. This possibility also requires close monitoring of Bay of Bengal depressions and cyclonic systems, which can produce intense rainfall along the southeast coast. Overall, 2026 may be better understood as a year of high monsoon variability rather than simply a weak monsoon year.

A warmer climate is changing the risks

The larger concern is that El Niño is now developing in a warmer climate system. Recent assessments indicate that India’s mean temperature during 2015-2024 was about 0.89°C above the 1901-1930 baseline. IMD also reports a significant all-India warming trend of about 0.68°C per 100 years during 1901-2024, with 2024 being the warmest year since records began in 1901. The tropical Indian Ocean has also warmed rapidly, at about 0.12°C per decade since 1950, while the broader Indian Ocean warmed at about 1.2°C per century during 1950-2020. A warmer atmosphere can hold nearly 7% more water vapour for every 1°C of warming, increasing the potential for short-duration, high-intensity rainfall events.

This means that a below-normal monsoon season can still produce damaging cloudbursts, flash floods and urban inundation. Recent studies using IMD gridded rainfall data show widespread extreme rainfall events over central India have increased nearly threefold since 1950. Updated analyses for 1951-2024 further indicate spatially uneven intensification of extreme precipitation over many parts of central India. The emerging risk is not simply less rain or more rain; it is uneven rainfall, delayed onset, long dry spells and sudden heavy downpours within the same season.

In the Telugu states, especially Telangana, Rayalaseema and South Coastal Andhra Pradesh, this variability has direct implications. A weak or delayed southwest monsoon can affect sowing, reservoir inflows and groundwater recharge. In Rayalaseema and south coastal districts, the northeast monsoon remains equally important for agriculture and drinking-water security. Therefore, seasonal rainfall forecasts must be translated into district-level advisories, crop-contingency planning and water-management decisions.

Key Scientific Signals For Public Understanding

The 2026 monsoon is a reminder that India’s rainfall future is becoming more complex. A developing El Niño, a below-normal IMD rainfall outlook, warming oceans and increasing rainfall extremes together point toward a more uncertain monsoon regime. Crop planning, reservoir operations, drought monitoring, groundwater conservation and district-level advisories must be strengthened before rainfall deficits become visible. The Indian monsoon will continue to sustain the country, but it may no longer follow the familiar rhythm of the past. In a warming world, India must prepare not only for weak monsoons, but also for delayed, uneven and extreme rainfall. The future of monsoon resilience will depend on how effectively science, governance, agriculture and local communities work together.

(The author Koteswararao Kundeti is a Senior Climate Analyst at UAE Weather Bureau.)