UN weather agency ranks 2026 among four warmest years

The World Meteorological Organization said Monday that 2026 will rank among the four warmest years on record. Its new State of the Climate Update puts the global average surface temperature for January through September at about 1.47C above the 1850–1900 pre-industrial average. The report came out on the first day of the COP31 climate summit in Antalya, Türkiye, which runs through November 20. The agency warned that a strengthening El Niño is likely to push temperatures higher before the year ends and to drive extreme weather well into 2027.wmo.int+1

The nine-month figure is above the full-year averages for 2025 and 2023 and only slightly below 2024, the warmest year on record. The past 12 years have each been the warmest on record, and the past four occupy the top four spots.deccanherald.com+1

An El Niño "off the charts"

El Niño has been strengthening since August, and the WMO expects it to reach record strength by December. The agency normally declares an El Niño when tropical Pacific sea surface temperatures run 0.5C above average. It now forecasts they may reach nearly four times that level between November 2026 and January 2027, Saulo told reporters. The WMO said the event could add another 0.1C to 0.2C to global temperatures.wmo.int+2

"The ongoing El Niño is forecast to be one of the strongest on record, and the heat it releases from the ocean will continue to fuel high temperatures and extreme weather into 2027," Saulo said. She noted that El Niño's biggest effect on global temperatures usually comes the year after it forms, and said the world "should therefore prepare for another record-breaking year in 2027".deccanherald.com+1

Record ocean heat and sea level

Ocean heat content is on track for a tenth straight year of records. Global mean sea level reached its highest point in the satellite record, which began in 1993. Atmospheric carbon dioxide reached about 426.8 parts per million in 2025, 53% above the level in 1750. The report also found that an April heatwave exposed an estimated 146.5 million people in India to extreme heat.wmo.int+1

Pressure on COP31

Over the next two weeks, negotiators will focus on moving away from fossil fuels and on finance for countries already facing severe climate impacts. The update only includes data through September, so it does not capture El Niño's most recent effects. The WMO will publish its final State of the Global Climate 2026 report in March 2027.cnn.com+1

UN Secretary-General António Guterres said, "We have entered a new age of climate extremes. A supersized El Niño is colliding with a planet already superheated by manmade climate change." He urged leaders to cut emissions faster and to deliver the finance that vulnerable countries need.wmo.int