IRI predicts a very strong El Niño by late 2026, raising climate risk for India

The International Research Institute released an ENSO forecast on September 21 indicating that the Nino 3.4 index, a primary measure of Pacific Ocean warmth, hit +3.0 °C in mid-September. Every one of the 22 climate models it evaluated—13 dynamical and nine statistical—projects very strong El Niño conditions lasting through the 2026-27 winter, assigning a 100 % probability of El Niño through February 2027 and a 61 % chance by mid-2027.

The forecast could rank among the strongest on record. Simultaneously, the IRI expects the Indian Ocean Dipole to turn strongly positive from September through December 2026 before easing toward neutral in early 2027; a positive IOD often coincides with El Niño but can also develop independently. While the institute cautions that the forecast does not provide precise rainfall or crop-output predictions, it notes that El Niño typically brings reduced monsoon rains, warmer and drier winters, and heightened stress on agriculture and water resources in India.