A potentially exceptionally strong El Niño is expected to intensify in the coming months, raising the risk of extreme weather across several parts of the world and with effects likely to continue into 2027, the World Meteorological Organization (WMO) has warned.
The United Nations weather agency said Thursday that the climate phenomenon is expected to reach “very strong” intensity towards the end of 2026 and is almost certain to persist through February 2027.
The warning comes as ocean temperatures in the central and eastern equatorial Pacific continue to rise, strengthening the atmospheric conditions associated with El Niño.
Why this El Niño is raising concern
El Niño is a naturally occurring climate pattern caused by unusually warm surface waters in the central and eastern tropical Pacific Ocean.
The warming affects atmospheric circulation, changing rainfall, temperature and wind patterns thousands of kilometres away from the Pacific.
WMO Secretary-General Celeste Saulo said the current event could become one of the strongest recorded since systematic monitoring began about four decades ago.
“If this trajectory continues, it may be stronger than anything since our monitoring began,” Saulo told reporters in Geneva.
The WMO said El Niño is expected to bring significant changes in rainfall and temperature patterns, increasing the risks of floods, drought and extreme heat.
The biggest effects may come after the peak
Although El Niño is expected to reach its peak towards the end of 2026, its influence will not necessarily end when the ocean phenomenon begins to weaken.
The WMO said the climate effects could extend well into 2027 because heat stored in the oceans is released gradually into the atmosphere.
A previous major El Niño in 2023-24 contributed to 2024 becoming the warmest year on record.
Saulo warned that another temperature record could be broken if current conditions continue.
What it could mean for weather patterns
El Niño does not produce the same weather impacts everywhere, and every event has its own characteristics.
However, strong El Niño events have historically been associated with drought in parts of the Amazon, Indonesia and Australia, disrupted monsoon patterns in India and major changes in rainfall across tropical regions.
For September to November, the WMO expects above-normal temperatures across almost all land areas.
The agency also forecasts rainfall patterns consistent with a strong El Niño, although the precise effects will vary from one region to another.
Pacific Ocean temperatures continue to climb
The warning is being driven in part by the rapid warming of the tropical Pacific.
Between May and July, sea surface temperatures in the central-eastern equatorial Pacific averaged about 1.5°C above normal.
Weekly readings from late July to mid-August were even higher, ranging from approximately 2.2°C to 2.6°C above average.
The WMO also reported that temperatures below the ocean surface were more than 8°C above average in some areas during July and early August.
The agency classifies El Niño events as weak, moderate, strong or very strong. Current forecasts indicate that the phenomenon could reach the highest category.
Warning for governments and key sectors
The potential scale of the event has prompted the WMO to call for early preparations.
Saulo warned that the effects could cause serious disruption to communities and economies, particularly in sectors that depend heavily on weather conditions.
Agriculture, water, health and energy systems are among those that could face increased pressure as rainfall and temperatures become more unpredictable.
“We are already seeing disruption and devastation from droughts and floods, and we expect these impacts to increase as El Niño intensifies,” Saulo said.
The WMO has urged disaster-management authorities to use available climate information to prepare communities before extreme weather strikes.
Climate change could make the heat worse
El Niño itself is not caused by climate change. It is part of a naturally recurring climate cycle that typically occurs every two to seven years and lasts about nine to 12 months.
However, climate change is increasing the baseline temperature of the planet, meaning an El Niño event now occurs against a warmer global background.
That combination can produce particularly intense heat.
UN Secretary-General Antonio Guterres described the situation as a warning that the world is entering increasingly unfamiliar climate conditions.
“El Nino is being supersized before our eyes,” Guterres said.
He called for faster climate action to reduce the risks facing communities around the world.
What happens next?
The WMO said there is an exceptionally high likelihood — close to 100 per cent — that the current El Niño conditions will continue through February 2027.
The immediate focus will therefore be on monitoring how quickly the Pacific Ocean continues to warm and how the resulting atmospheric changes translate into weather conditions around the world.
For governments, communities and climate-sensitive sectors, the warning provides an opportunity to strengthen preparedness before the strongest impacts are felt.
