El Niño Sets the Odds, Not the Outcome: What 1997, 2015 and 2026 Reveal About India's Monsoon

A Forecasting Problem India Has Been Solving Since 1877

India's attempt to read the monsoon began with catastrophe. After the drought and famine of 1877, the government asked H.F. Blanford to estimate the coming rains and the first regular forecast followed on 4 June 1886. Gilbert Walker, who led the department from 1904 to 1924, then tied the monsoon to global conditions through the Southern Oscillation.

Walker's great insight was that India's rain could be influenced from far beyond India. The 2026 monsoon, closing at 87.4% of its long-period average, shows that this insight is still only part of the answer. The easy reading of 2026 is that El Niño arrived and the rains failed.

History does not support so simple a rule. Only seven of the 16 El Niño years since 1950 were linked with below-normal monsoon rain.

Three El Niños, Three Different Oceans

1997 is the year that breaks the rule. A very strong El Niño coincided with a monsoon at 102% of average, as a favourable Indian Ocean Dipole offset much of the Pacific's drying effect. 2015 is the warning against treating that rescue as automatic.

That extreme El Niño came with only a weak positive dipole, unlike the very strong dipole of 1997-98. The season closed at 86% of average. 2026 offered less help still. The IMD's September outlook described neutral dipole conditions and expected its own model to keep them neutral through the month, though international centres saw a possible positive turn.

Timing adds to the problem. The dipole is usually strongest from September to November, when the monsoon is ending or over. Here the parallel with 1997 has limits. It teaches that the Indian Ocean can matter, not that it will always rescue India.

Warming patterns also differed: the warmest waters of 1997 lay further east and research since 2006 has linked warmth in the mid-Pacific with higher odds of weak Indian rain. No single index can explain all three years.

The Failure the National Figure Hides

Walker's generation looked for one monsoon verdict for the whole of India. Today, that single number is what misleads. Central India received 97% of its normal rain and Northwest India 94.1%. The South Peninsula received 76%, its fourth-lowest total since 1901.

East and Northeast India received 74%, the driest season in a record reaching back to 1901. A farmer in Central India and a farmer in the Northeast therefore lived through two different monsoons, though both appear under the same 12.6% shortfall.