- Latest climate model forecasts suggest a high probability of a very severe El Niño in the October–December 2026 period.
- Not all El Niño events result in droughts over India, and some drought years have occurred without El Niño conditions. Nevertheless, the probability of below-normal monsoon rainfall over India is quite high.
- The occurrence of a poor monsoon cannot be prevented, but its adverse impacts can certainly be reduced through planning, preparedness and adaptation strategies to minimise potential impacts, particularly on agriculture and water resources.
Several global climate agencies have recently indicated the possible development of a very severe El Niño by the end of this year, along with concerns regarding its potential global impacts, including on the Indian monsoon.
El Niño is a naturally occurring climate phenomenon characterised by sustained warming of sea surface temperatures over the central and eastern equatorial Pacific Ocean for several consecutive months. It represents the warm phase of the broader El Niño-Southern Oscillation (ENSO) cycle, which also includes its opposite phase, La Niña, and a neutral phase.
Variations in tropical Pacific sea surface temperatures associated with El Niño alter global atmospheric circulation patterns and influence rainfall, droughts, storms, agriculture, water resources, marine ecosystems, and economies across many regions of the world, including India.
The intensity of El Niño is commonly monitored using sea surface temperature anomalies over the Niño 3.4 region of the equatorial central Pacific Ocean. An El Niño event is declared when the three-month running mean sea surface temperature anomaly in the Niño 3.4 region remains at least +0.5°C above normal for five consecutive overlapping three-month seasons. El Niño events are further classified based on the magnitude of these temperature anomalies. When the Niño 3.4 anomaly exceeds +2.0°C, the event is generally categorised as a very strong El Niño (informally a “super” El Niño). Since 1951, 28 El Niño events of varying intensity have occurred, most of them weak. The most recent El Niño developed in 2023.
The current outlook
Recent observations indicate rapid warming of the equatorial Pacific Ocean, accompanied by a substantial build-up of warm water beneath the ocean surface. This enhanced subsurface heat content is widely regarded as a precursor to the development of a strong El Niño event.
Latest climate model forecasts suggest that this warming is likely to intensify further, with a high probability of a very severe El Niño developing during the October-December 2026 period. Some model projections indicate that the peak intensity may exceed +2.0°C in the Niño 3.4 region. There is broad consensus among global climate models regarding the development of an El Niño event this year and its likely peak during late 2026.
However, uncertainty still remains regarding its ultimate strength.
Indian monsoon and its relationship with El Niño
The southwest monsoon season from June to September accounts for nearly 70-90% of India’s annual rainfall. The lives and livelihoods of millions of people are closely linked to the performance of the monsoon. A good monsoon season usually supports higher agricultural production and contributes positively to economic growth. Conversely, weak monsoons can lead to droughts, food shortages, inflation, and broader economic stress. The economic importance of the monsoon was aptly captured by former Finance Minister Pranab Mukherjee in his 2011 Budget speech: “The monsoon is the real Finance Minister of India.”
The average seasonal rainfall over India during June-September is about 87 cm, with a coefficient of variation of nearly 10%. A monsoon season is generally considered deficient when rainfall falls below 90% of the Long Period Average. During 1901-2025, India experienced 17 deficient monsoon years, with the most severe drought occurring in 1972 when rainfall deficiency reached 22%.
Year-to-year monsoon variability is influenced by several large-scale climate factors, including ENSO, the Indian Ocean Dipole (IOD), Atlantic Ocean conditions, and land-surface conditions. Among these, ENSO remains the single most influential factor.
However, there is no one-to-one correspondence between El Niño and deficient monsoon rainfall. Not all El Niño events result in droughts over India, and some drought years have occurred without El Niño conditions, such as in 1974 and 1979. Nevertheless, if we consider all moderate, severe, and very severe El Niño events since 1951, the probability of below-normal monsoon rainfall over India is quite high. El Niño years are also often associated with an increase in the frequency and duration of monsoon “break” periods.
Since 1951, three “Super” El Niño events have occurred — in 1982, 1997, and 2015. The Indian monsoon rainfall was significantly deficient during 1982 and 2015. However, despite the strong 1997 El Niño, India experienced near-normal monsoon rainfall. This was largely attributed to the compensating influence of a strong positive Indian Ocean Dipole.
Prospects for the 2026 monsoon
Current climate forecasts indicate a high probability of a below-normal Indian summer monsoon in 2026, primarily due to the likely development of a strong El Niño event in the equatorial Pacific Ocean.
In its updated long-range forecast issued on May 29, 2026, the India Meteorological Department (IMD) projected the seasonal rainfall over the country at about 90% of the Long Period Average (LPA), with a 60% probability of a deficient monsoon. The forecast also indicates an increased likelihood of below-normal rainfall across most parts of the country, except over Northeast India. Similar outlooks issued by several leading global climate centres likewise suggest a heightened probability of below-normal or deficient rainfall during the 2026 southwest monsoon season.
Although not every El Niño event results in deficient monsoon rainfall over India, the risk of a weak monsoon increases substantially when the El Niño is particularly strong, as currently projected by many climate models.
Some climate agencies also predict the development of a positive Indian Ocean Dipole (IOD) event during the latter part of the monsoon season. A positive IOD can partially offset the adverse influence of El Niño on the Indian monsoon. However, forecasts of the IOD at this lead time remain highly uncertain, and its predictability is considerably lower than that of El Niño.
Therefore, while the projected positive IOD offers some hope, it may not be sufficient to fully counteract the impact of a strong El Niño on the 2026 monsoon.
Potential impacts of a deficient monsoon in 2026
Historically, deficient monsoon seasons have had wide-ranging consequences for the Indian economy because the monsoon remains central to agriculture, water security, rural livelihoods, and energy production.
Agriculture is usually the first and most severely affected sector. Nearly half of India’s net sown area still depends on rainfall. Rainfed agriculture in central, western, and peninsular India becomes particularly vulnerable during deficient monsoon years. Poor rainfall can delay sowing, reduce cropped area, create moisture stress during critical crop growth stages, and lower crop yields. Kharif crops are especially vulnerable because they depend heavily on monsoon rainfall during June–September.
Lower agricultural production can reduce foodgrain availability and contribute to higher food inflation, which may spill over into overall retail inflation and complicate monetary policy management. Reduced farm income can also weaken rural demand and adversely affect the broader rural economy.
Deficient monsoon rainfall also reduces storage levels in major reservoirs, affecting irrigation, drinking water supply, industrial water use, and hydropower generation. Groundwater recharge declines sharply during drought years, even as extraction increases, leading to falling water tables. Urban areas and industries may experience water shortages. Reduced hydropower generation can further increase dependence on thermal power, raising coal demand and power generation costs.
At the macroeconomic level, a weak monsoon can contribute to slower GDP growth, increased fiscal burden through drought relief and support measures, higher inflation, and additional monetary policy challenges. Although the Indian economy today is more resilient than in the past, a severe monsoon failure can still significantly affect agriculture, inflation, water security, energy production, and rural livelihoods, with consequences extending across the broader economy.
There is, however, no reason for panic. What is important is to formulate and implement effective preparedness and adaptation strategies to minimise potential impacts, particularly on agriculture and water resources. The occurrence of a poor monsoon cannot be prevented, but its adverse impacts can certainly be reduced.
India today possesses substantial scientific knowledge, improved climate prediction capabilities, and better observational systems. The need of the hour is to use these capabilities effectively for preparedness, planning, risk management, and climate adaptation.
Banner image: A man exits a foot bridge over a flooded street after heavy monsoon rains in Guwahati, Assam in 2025. Representative image. (AP Photo/Anupam Nath)
The author is the Vice Chancellor, Atria University, Bengaluru and the Former Secretary, Ministry of Earth Sciences, Government of India.
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