Warm waters surging across the tropical Pacific are setting the stage for a major El Niño, and the World Meteorological Organisation says the developing pattern is poised to push global temperatures higher and intensify extremes in weather and rainfall in the months ahead.
The agency said its forecasting models indicate an 80% certainty that above-average temperatures will be recorded almost everywhere from June to August.
It also put the likelihood at 90% that El Niño’s warming influence will persist and strengthen through November and beyond.
UN Secretary General António Guterres urged governments and communities to take the WMO’s update as an urgent climate warning, cautioning that El Niño conditions will pour fuel on the fire of an already warming world.
He said the impacts will strike harder, reach farther and cross borders with devastating speed.
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Watch: El Niño arriving with 90% certainty, says UN’s Guterres
The ocean-temperature shifts that underpin El Niño rank among the most powerful naturally occurring climate patterns on Earth.
The phenomenon is defined by unusually warm sea-surface temperatures across the central and eastern Equatorial Pacific.
El Niño events typically recur every two to seven years and generally last about nine to 12 months.
They usually begin to form between March and June, peak between November and February, and their influence on global temperatures is often most evident in the second year after development.
The WMO said there is no evidence that climate change is increasing the frequency or intensity of El Niño events.
However, it noted that additional background heating in the atmosphere linked to climate change can amplify the impacts associated with an El Niño.
Global conditions swing between El Niño and its opposite phase, La Niña, with neutral periods in between.
El Niño conditions could affect global temperature and rainfall patterns
Meteorologists say that while global temperatures are expected to be elevated this year, next year 2027 is already shaping up to be the hottest year on record.
WMO Secretary General Andrea Celeste Saulo said the world should brace for a potentially strong El Niño that could worsen drought, trigger heavier rainfall and raise the risk of heatwaves on land and in the ocean.
The last El Niño, in 2023 and 2024, ranked among the five strongest ever recorded and contributed to the record global temperatures observed in 2024.
El Niño’s typical footprint includes increased rainfall across parts of southern South America, the southern United States, areas of the Horn of Africa and central Asia, alongside drier conditions over Central America, northern South America, the Caribbean, Australia, Indonesia and parts of southern Asia.
Its warmer waters also tend to energise hurricanes in the central and eastern Pacific Ocean.
But El Niño usually suppresses hurricane formation in the Atlantic Basin, where a quieter storm season can have knock-on effects for Ireland.
WMO is warning of above normal temperatures
WMO forecast maps published with the El Niño update, showing projected warming and precipitation patterns, indicate Ireland is likely to see reduced rainfall as the event develops.
Ireland was among numerous European countries that experienced record-breaking temperatures last month.
At the same time, WMO signals suggest that while Irish temperatures are expected to be above normal, the country may avoid the strongest warming effects associated with the approaching El Niño.
Regional climate centres are forecasting “below-normal” rainfall for the crucial June-September rainy season in the northern Greater Horn of Africa; below-average monsoon rainfall in south Asia; and drier, warmer summer conditions in central America.
In the northern hemisphere summer, El Niño-linked warm waters can help fuel hurricanes in the central and eastern Pacific while hampering their development in the Atlantic Ocean.
The WMO said advance notice is intended to support preparedness, particularly in climate-sensitive sectors such as agriculture, water management, energy and health.
Additional reporting AFP
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