A developing El Niño has become the strongest on record by some measures, weeks before its expected peak later this year. The phenomenon is already affecting weather worldwide, with wildfires in Indonesia affecting about 12.5 million people, while scientists assess whether its unprecedented strength will produce equally severe impacts.

Daily sea surface temperatures in a key central-eastern Pacific region reached 3.05°C above average on 19 September, surpassing the previous record of 3.02°C set in 2015. Other measures, including the Relative Oceanic Niño Index, have not yet broken records, but may do so; associated effects include India’s monsoon rainfall running 15% below normal, no Atlantic hurricanes so far in 2026, and increased risks of drought, wildfires, storms and flooding in several regions.