India is staring at a ‘below normal’ southwest monsoon, the India Meteorological Department warned for the first time in 11 years in its April forecast. Between the monsoon months of June-September, India is likely to receive only 92% of the Long Period Average (LPA) of 87 cm this monsoon, M. Ravichandran, Secretary, Ministry of Earth Sciences said at a press briefing on Monday.

India last experienced reduced monsoon rainfall in 2023, when the IMD had warned of “near normal” rainfall at 96% of the LPA. In 2015, the IMD’s warning of below normal rain -- at 93% of the LPA -- turned out to be an underestimate. Actual rainfall was recorded at 86% and it ended as one of India’s worst drought years.

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M. Mohapatra, Director-General, IMD, said the main reason for this year’s below-normal monsoon warning is the likely development of an El Nino — a periodic warming of the Central Equatorial Pacific, which in the 16 years it has emerged since 1950, had depressed India’s monsoon rainfall nine times. With disruptions of fertilizer supply ahead of the Kharif season anticipated in the wake of the West Asia war, insufficient rain could impact farming in the country, which is significantly rainfed.

At present, “weak” La Niña-like conditions – the converse of an El Nino — are transitioning to neutral conditions over the equatorial Pacific. The effects of the El Nino are only likely to come into full effect in the second half of the monsoon, during the months of August and September.

Mr. Mohapatra said that despite the links between an El Nino and weak monsoon, two factors could blunt its impact. The first is the so called ‘positive’ IOD (Indian Ocean Dipole), a condition that is likely to develop towards the end of the southwest monsoon season. The second is that the extent of northern hemisphere snow cover from January to March 2026 has been slightly below normal. The dipole refers to oscillations of sea-surface temperatures between the western (near Africa) and eastern (near Indonesia) tropical Indian Ocean. A “positive” dipole and reduced snow cover generally tend to bring more rain to India and can offset El Nino’s “negative” impact, Mr Mohapatra said.

2024 and 2025 have been years of surplus monsoon. Save for 2023, India has received “normal” or excess rainfall in all years since 2020.

Last week, private weather forecaster Skymet also forecast “below normal” monsoon with an expectation of 94% of the LPA.

The IMD is expected to update its monsoon forecast in May. The IMD’s past history shows that its forecasts of a weak monsoon in April generally hold true though there have been several instances of the IMD predicting a “normal” monsoon and India staring at a drought.

In 2002, the IMD predicted a normal monsoon but India experienced one of its worst droughts (81% of LPA). In 2009, the IMD’s April forecast predicted a near-normal monsoon (96–98% of LPA) but actual rainfall was around 77% of the LPA, resulting in one of the worst droughts in over a century. In 2018, IMD’s April forecast predicted 97% of normal levels, and even the May update held the figure at 97%, but actual rainfall turned out to be 91% — well below normal. The IMD’s official parlance doesn’t use the term “drought” and refers to rain less than 90% of the LPA as “deficient”.