The cooling La Niña weather phenomenon may return between September and November, but even if it does, global temperatures are expected to be above average, the United Nations has said.
La Niña is a naturally occurring climate phenomenon that cools surface temperatures in the central and eastern equatorial Pacific Ocean. It brings changes in winds, pressure and rainfall patterns.
Conditions oscillate between La Niña and its opposite, El Niño, with neutral conditions in between.
After a brief spell of weak La Niña conditions, neutral conditions have persisted since March, the UN’s World Meteorological Organization (WMO) said.
“There is a 55% chance for sea surface temperatures in the equatorial Pacific to cool to La Niña levels” between September and November, it said.
“For October to December 2025, the probability of La Niña conditions slightly increases to about 60%,” the weather and climate agency added.
There is little chance of El Niño developing during September to December.
In many locations, especially in the tropics, La Niña produces the opposite climate impacts to El Niño, which heats up the surface of the oceans, leading to drought in some parts of the world and triggering heavy downpours elsewhere.
The unusually protracted 2020-2023 La Niña was the first “triple-dip” La Niña of the 21st century – and only the third since 1950. It intensified drought and flooding.
However, despite La Niña’s cooling effect, it did nothing to break the run of exceptionally hot years. The past 10 years make up the hottest 10 individual years ever recorded.
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Temperatures have remained at record or near-record levels even after El Niño conditions faded last year – with 2024 the hottest year on record.
The WMO underlined that naturally occurring climate events such as La Niña and El Niño take place against the backdrop of human-induced climate change, “which is increasing global temperatures, exacerbating extreme weather, and impacting seasonal rainfall and temperature patterns”.
The WMO’s latest update said temperatures between September and November were expected to be above normal in much of the northern hemisphere and large parts of the southern hemisphere.
