India’s weak southwest monsoon and a 40% June rainfall deficit have sharpened focus on the Indian Ocean Dipole (IOD)
It's a key climate pattern that can influence rains, crop yields and the broader economy
IMD says only a strong positive IOD can partly offset El Niño, shaping food prices, inflation and even electricity demand
India’s southwest monsoon has entered a crucial phase, with rainfall remaining below normal after a weak start to the season. While weather experts continue to monitor the strengthening El Niño over the Pacific Ocean, another climate pattern closer to home — the Indian Ocean Dipole (IOD) — has come into focus for its potential influence on rainfall, agriculture and the broader economy.
India reportedly recorded a rainfall deficit of around 40% during June compared with the long-period average, raising concerns over crop prospects in several parts of the country.
1 June 2026
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However, meteorologists say the IOD could still play an important role if it shifts into a positive phase later in the monsoon.
What Is The Indian Ocean Dipole?
The IOD is a climate phenomenon that measures differences in sea surface temperatures between the western Indian Ocean near East Africa and the eastern Indian Ocean close to Indonesia.
The phenomenon operates in three phases — positive, negative and neutral.
A positive IOD develops when waters in the western Indian Ocean become warmer than those in the east. This strengthens moisture-bearing winds towards India and East Africa, often supporting monsoon rainfall.
A negative IOD produces the opposite effect by directing moisture away from the Indian subcontinent, while a neutral phase has little influence on rainfall patterns.
A strong positive IOD helped offset one of the strongest El Niño events on record in 1997, allowing India to finish the monsoon season with rainfall around 2% above normal despite expectations of severe drought.
How is the IOD Building Up Right Now?
The IMD currently expects moderate to strong El Niño conditions during the southwest monsoon while forecasting neutral IOD conditions throughout the season.
Australia's Bureau of Meteorology, however, has indicated a possibility of a positive IOD emerging later in the season, but forecasts differ on both its timing and strength.
"The El Niño is like the big brother, and the IOD cannot fully compensate," said Mrutyunjay Mohapatra, Director-General of the India Meteorological Department (IMD), as per a report by The Hindu.
He added that only a strong positive IOD has historically been capable of significantly offsetting El Niño's impact.
Why Farmers Watch The IOD Closely
For farmers, the timing and distribution of rainfall are often as important as the seasonal total.
September is particularly important because many standing kharif crops enter their grain-filling stage, when adequate moisture is essential.
How Monsoon Patterns Affect Food Prices and Inflation
Rainfall directly affects agricultural output, particularly kharif crops such as rice, pulses, cotton and oilseeds that depend heavily on the southwest monsoon.
Poor rainfall can reduce yields, tighten supplies and eventually push up food prices.
Large parts of central, eastern and north-eastern India experienced deficient rainfall during June, making the coming weeks critical for crop development.
Economists generally monitor monsoon progress closely because food inflation remains one of the biggest contributors to overall retail inflation in India.
A prolonged rainfall deficit can therefore influence household budgets through higher prices of vegetables, cereals and pulses.
Lower agricultural production often creates supply shortages that feed into food inflation. Higher food prices can, in turn, influence overall inflation and monetary policy decisions.
If rainfall improves during July and August, pressure on food prices may ease. However, if El Niño strengthens without support from a positive IOD, concerns over crop output and inflation could persist.
Can IOD Change Electricity Demand?
Weather patterns can also affect electricity consumption. A weak monsoon generally leads to hotter conditions across many regions, increasing demand for air conditioning and cooling.
Reduced rainfall may also affect hydropower generation in some river basins, potentially increasing dependence on thermal power during periods of peak demand.
Although the IOD itself does not directly determine electricity consumption, its influence on rainfall can indirectly affect both power demand and energy supply.
