The El Niño weather phenomenon is set to intensify ahead of its forecast peak in December, with sea-surface temperatures in the central and eastern tropical Pacific expected to reach record levels.
The World Meteorological Organization (WMO), in a statement issued on Thursday, October 8, 2026, stated that the strengthening El Niño is likely to influence weather patterns across the globe, bringing above-average temperatures to many regions and shifting rainfall patterns.
The changes could increase the risk of drought and floods in different parts of the world, according to the WMO’s latest Global Seasonal Climate Update.
“El Niño will continue to intensify ahead of its forecast peak in December. Sea-surface temperatures in the central & eastern tropical Pacific are set to increase to record levels,” WMO’s statement reads.
WMO Secretary-General Celeste Saulo said the climate phenomenon was strengthening rapidly and could become one of the strongest El Niño events recorded since at least 1950.
“El Niño is firmly established and strengthening rapidly. WMO forecasts indicate a near-100 per cent likelihood that it will persist through February 2027, potentially being one of the strongest since at least 1950,” Saulo said.
The forecast is based on a consensus from 13 national and international climate centres, using real-time data from ocean buoys, satellites and radiosondes coordinated by the WMO.
Sea-surface temperatures in the central-eastern equatorial Pacific, measured using the Niño 3.4 index, have already risen sharply.
The index increased from an average of 1.6°C above normal in June 2026 to 2.5°C above normal in August.
For October, November and December, the seasonal average is forecast to reach approximately 3.7°C above normal, with the peak expected around December.
According to the WMO, this would be the highest level since observations began and exceed the previous record of 2.6°C recorded between November 2015 and January 2016.
More heat and changing rainfall patterns
Saulo said the warming associated with a strong El Niño is linked to heat stored in the ocean being released into the atmosphere.
“El Niño doesn’t add new heat to the planet. It releases heat the ocean has already been storing beneath the surface – which is why a strong event so often becomes one of the hottest years measured (as with 2024),” she said.
“The ocean it’s drawing from is the warmest we’ve ever measured it. There is simply more heat available to release,” Saulo added.
The WMO said the strengthening event is expected to drive weather patterns and affect communities, ecosystems and economies around the world.
It also warned that rainfall patterns are likely to shift, increasing the risk of both drought and flooding in different regions.
Indian Ocean Dipole also influences outlook
The WMO said other ocean conditions are also contributing to the seasonal outlook.
A positive Indian Ocean Dipole (IOD), which can influence rainfall patterns around the Indian Ocean, is expected to peak in October before declining.
Its October-December seasonal anomaly is forecast at about 0.5°C.
Meanwhile, sea-surface temperatures in the equatorial Atlantic are expected to remain above normal, adding to the broader climate conditions influencing global weather patterns.
