El Niño Could Become Strongest in Four Decades, WMO Warns

The United Nations' weather agency has warned that a rapidly intensifying El Niño could become the strongest recorded since monitoring began four decades ago, raising the risk of extreme heat, floods and droughts across the world.

The World Meteorological Organization (WMO) said Thursday that the naturally occurring climate phenomenon is expected to strengthen to “very strong” intensity in the coming months and is almost certain to persist through February.

WMO Secretary-General Celeste Saulo said the current trajectory was unprecedented in the agency's four decades of monitoring.

“If this trajectory continues, it may be stronger than anything since our monitoring began — so literally off the charts we have used for the past four decades,” Saulo told reporters in Geneva.

The phenomenon is expected to peak towards the end of 2026, although its effects on global temperatures and weather patterns could continue into 2027.

El Niño Threatens More Extreme Weather

El Niño occurs when surface waters in the central and eastern equatorial Pacific Ocean become unusually warm, triggering changes in atmospheric circulation, winds, pressure and rainfall patterns around the world.

The WMO said the current event is already firmly established and is expected to intensify further.

“El Niño is firmly established and will intensify into a very strong event in the coming months, with big impacts on rainfall and temperature patterns and associated risks of floods, drought and extreme heat,” the agency said.

The warning has placed governments and disaster-response agencies on alert as they prepare for potentially severe weather conditions in vulnerable regions.

UN Warns World Is in “Danger Zone”

UN Secretary-General António Guterres described the developing El Niño as a major warning for a planet already experiencing record-breaking temperatures.

“El Niño is being supersized before our eyes,” Guterres said.

He warned that rising ocean and atmospheric temperatures were pushing the planet into increasingly dangerous climate territory.

“The science leaves no room for doubt: the planet is in uncharted waters, and those waters are heating up.”

Guterres said governments must accelerate climate action and strengthen measures to protect populations from the growing risks associated with extreme weather.

“The race now is between rising risks and our commitment to take climate action and protect people. We must win that race,” he said.

Risk of Major Economic Disruption

WMO chief Saulo warned that an exceptionally strong El Niño could have serious consequences for communities and economies around the world.

“This exceptional El Niño... has the potential to deliver a massive blow to communities and economies across the world,” she said.

The agency is already seeing disruption caused by droughts and floods and expects those impacts to intensify as the El Niño event strengthens.

Saulo urged disaster-management authorities and climate-sensitive sectors, including agriculture, health, energy and water, to accelerate preparations.

She warned there was “no time to lose” in preparing for the potential consequences.

2024 Heat Record Could Be Broken

The developing El Niño could also push global temperatures to new highs.

The powerful 2023–24 El Niño contributed to 2024 becoming the warmest year on record, according to the WMO.

Saulo said the latest event could potentially produce another temperature record.

“We should not be surprised if this record is broken,” she said.

Although El Niño itself is a natural climate phenomenon and is not caused by climate change, scientists expect it to amplify the warming effects of a planet already being heated by greenhouse-gas emissions from fossil fuels.

Pacific Ocean Shows Strong Warming

The WMO said unusually warm ocean conditions across the tropical Pacific are fuelling the intensification of the current event.

The index used to measure sea-surface temperature anomalies in the central and eastern equatorial Pacific showed temperatures averaging 1.5°C above normal between May and July.

Weekly readings between late July and mid-August rose further, ranging from approximately 2.2°C to 2.6°C above average.

In some areas beneath the ocean surface, temperatures were more than 8°C above average during July and early August.

The WMO said the ocean measurements indicate that El Niño is continuing to strengthen.

Global Weather Patterns Expected to Shift

El Niño can influence weather thousands of kilometres away from the tropical Pacific.

Its effects can include drought in parts of the Amazon, Indonesia and Australia, disruptions to monsoon patterns in India and significant changes in rainfall across tropical regions.

For September through November, WMO forecasts indicate a heightened likelihood of above-normal temperatures across almost all land areas.

The agency also expects rainfall patterns associated with a strong El Niño to emerge more clearly during the period.

What Happens Next?

El Niño typically occurs every two to seven years and lasts between nine and 12 months.

The climate system alternates between El Niño and its cooler counterpart, La Niña, with neutral conditions occurring between the two phases.

The WMO said there is an “exceptionally high likelihood of nearly 100 percent” that the current El Niño will continue through February.

While the event is expected to peak later this year, its influence on global temperatures and weather could extend well into 2027.

With the possibility of an exceptionally strong event ahead, governments and climate-sensitive industries are being urged to strengthen preparedness for extreme heat, flooding, drought and other weather-related disruptions.