“An El Niño event is forecast for late 2026, increasing the likelihood that the following year, 2027, will be the next record year,” said Leon Hermanson, lead author of the bulletin, which summarizes forecasts from 13 different institutions. The five-year average temperature forecasts for the central tropical Pacific indicate, according to the WMO, “a trend toward El Niño conditions,” particularly in 2027 and 2028. El Niño is characterized by an increase in surface temperatures in the central and eastern equatorial Pacific. It typically occurs every two to seven years and lasts about nine to twelve months.
The last El Niño event, in 2023 and 2024, made those years the two warmest on record. This cyclical phenomenon has a ripple effect on global climate for several months.
According to the report, released as parts of Europe have been experiencing an exceptional heatwave for a month of May for several days, global average temperatures are expected to remain very high over the next five years, close to historic highs. According to the WMO, between 2026 and 2030, global average annual surface temperatures will rise by 1.3°C to 1.9°C above pre-industrial levels (1850–1900). And it is “very likely” (91%) that the average surface temperature will temporarily exceed 1.5°C above the 1850-1900 average for at least one year between 2026 and 2030. This threshold was also temporarily exceeded in 2024, when the average global surface temperature was about 1.55°C above pre-industrial levels. According to the bulletin, it is “extremely unlikely” (less than 1%) that the average global surface temperature will exceed 2°C above the 1850-1900 average during any of the next five years
