GENEVA, April 24 (Xinhua) --An El Nino event is expected to develop from mid-2026, impacting global temperature and rainfall patterns, said the World Meteorological Organization (WMO) in a news release on Friday.

A man jumps into a pond of Hampstead Heath in London, Britain, on June 20, 2025. Britain recorded its hottest day of the year on Thursday as an amber heat health alert was issued across England. (Photo: Xinhua)

The latest monthly Global Seasonal Climate Update from the WMO signals a clear shift in the Equatorial Pacific: sea-surface temperatures are rising rapidly, pointing to a likely return of El Nino conditions as early as May-July 2026. Forecasts indicate there is a "nearly global dominance of above-normal land surface temperatures" in the upcoming three-month period, and regional variations in rainfall patterns.

"After a period of neutral conditions at the start of the year, climate models are now strongly aligned, and there is high confidence in the onset of El Nino, followed by further intensification in the months that follow," said Wilfran Moufouma Okia, chief of climate prediction at WMO in the press release.

The WMO explains that El Nino is characterized by a warming of ocean surface temperatures in the central and eastern Equatorial Pacific. It typically occurs every two to seven years and lasts around nine to twelve months.

El Nino events affect temperature and rainfall patterns in different regions, and typically have a warming effect on the global climate. Thus, 2024 was the hottest year on record because of the combination of the powerful 2023-2024 El Nino and human-induced climate change from greenhouse gas emissions.

There is no evidence that climate change increases the frequency or intensity of El Nino events. But it can amplify associated impacts because a warmer ocean and atmosphere increases the availability of energy and moisture for extreme weather events such as heatwaves and heavy rainfall.

Each El Nino event is unique in terms of its evolution, spatial pattern and impacts. However, it is typically associated with increased rainfall in parts of southern South America, the southern United States, the Horn of Africa and central Asia, and drought over Australia, Indonesia, and parts of southern Asia.

During the Boreal summer, El Nino's warm water can fuel hurricanes in the central/eastern Pacific Ocean, while it hinders hurricane formation in the Atlantic Basin.