A severe El Niño could begin in a matter of weeks and will “pour fuel on the fire of a warming world”, UN ​Secretary-General Antonio Guterres has warned.

The UN’s World Meteorological Organisation said the looming El Nino would drive up global temperatures and increase the risk ‌of extreme weather in coming months.

In Australia, the weather pattern could lead to drought conditions which can damage crops, affect livestock and impact the food chain.

Some ​national ​weather agencies have forecast the strongest El Nino in a ​decade.

However, the WMO said there was still uncertainty about the strength as some models did not predict a strong El Nino.

The most recent El Nino, in 2023-24, contributed to making 2024 the hottest year on record.

El Nino is a periodic warming of sea surface temperatures in the central and eastern Pacific Ocean. It typically lasts between ‌nine and 12 months.

The WMO predicted above-average temperatures in most parts of the world from June to August.

The WMO said it was likely the El Nino would continue until November.

“We need to prepare for a potentially strong El Nino event — which will exacerbate drought and heavy rainfall and increase the risk of heatwaves both on land and in the ‌ocean,” WMO Secretary-General Celeste ‌Saulo said late on Tuesday (AEST).

The weather pattern ⁠is known to disrupt regional climates, potentially bringing warmer temperatures across the globe.

It can increase rainfall in ​southern South America, the southern US, parts of the Horn of Africa and central Asia.

It could also cause drought in Australia, central America, Indonesia, and sections of southern Asia, and lead to hurricanes in the central and eastern Pacific Ocean, the WMO said.

Drier weather is anticipated across Asia in the second half of ‌2026.

“Extreme heat alone is ⁠already one of the deadliest climate hazards we face, and an El Nino event ‌could intensify ​the threat,” Saulo said.

The risks include more heat-related illness, a wider spread of vector-borne diseases and increased pressure on food and water systems.

“Communities that were ​already struggling ‌will be pushed farther beyond their limits,” she said.

A shift had been observed in the Equatorial Pacific, with sea surface temperatures rising rapidly from ​late April to mid-May, suggesting El Nino conditions were developing, the WMO said.

The agency said it has observed unusually warm subsurface conditions across the tropical Pacific with temperatures more than six degrees above average, creating a reservoir of heat that is driving surface warming.

-with AAP