This year’s El Niño is expected to intensify before peaking in December and has a near-100% chance of lasting through February 2027, the World Meteorological Organization (WMO) said Thursday, warning that sea surface temperatures could reach record levels.

“WMO forecasts indicate a near-100% likelihood that El Niño will persist through February 2027, potentially being one of the strongest since at least 1950,” WMO Secretary-General Celeste Saulo said in a statement accompanying the organisation’s monthly climate bulletin.

The UN weather agency said sea surface temperatures in the central and eastern tropical Pacific, the region at the heart of the El Niño phenomenon, are expected to reach 3.7C (6.7F) above normal between October and December.

That forecast anomaly is significantly higher than the previous record of 2.6C recorded between November 2015 and January 2016, it said.

“The ocean it’s drawing from is the warmest we’ve ever measured it. There is simply more heat available to release,” Saulo said.

El Niño is the warm phase of the naturally occurring El Niño-Southern Oscillation cycle, a climate pattern that influences weather around the world. It tends to raise global temperatures and disrupt rainfall patterns across large regions, causing drought in some areas and heavy rainfall in others. The phenomenon typically occurs every two to seven years.

Mean global temperatures in August reached 16.96C, tying with July 2023 as the hottest month on record, according to the European Union’s Copernicus Climate Change Service.

Researchers at the University of Chicago’s Climate Impact Lab predicted last month that this year’s “super El Niño” could result in as many as 451,000 excess deaths worldwide between June and February 2027.