May ranked 2nd-warmest on record amid early European heat wave: EU's climate change service

May 2026 was the second warmest May globally since records began, with exceptional ocean and land temperatures and an unusually early heat wave in western Europe, the Copernicus Climate Change Service (C3S) of the European Centre for Medium-Range Weather Forecasts (ECMWF) said on Wednesday.

The global average surface air temperature in May reached 15.81°C (60.45°F), which is 0.55°C above the 1991-2020 average and only lower than May 2024, according to a statement.

Sea surface temperatures remained near record highs, with the tropical Pacific continuing to show strong warming as conditions trend towards a developing El Nino event.

Europe experienced a rapid shift from cooler-than-average conditions to extreme heat in the second half of the month.

Western Europe, including France, the United Kingdom, Ireland and Portugal, saw one of the most intense early-season heat waves on record, with numerous temperature records broken for May.

"Feels-like" temperatures reached between 35°C and 40°C in several regions, creating severe heat-stress conditions.

"In Europe, an unusually early and intense heat wave demonstrates how quickly climate extremes are becoming the new normal rather than the exception," strategic lead for climate at ECMWF Samantha Burgess said.

While parts of western and southern Europe, including Spain and Italy, were drier than average, flooding affected Türkiye, Bulgaria and Moldova.

Northern Europe and parts of Scandinavia recorded wetter-than-average conditions, contrasting with widespread dryness across central and eastern Europe, where river flows fell below average in major basins, including the Danube and Vistula.

Outside Europe, wetter-than-average conditions were observed in northern and southeastern North America, parts of Asia, western China, Brazil, southern Africa and Australia.

In contrast, drier-than-average conditions affected the central United States, much of South America, Madagascar and southwestern Australia.

Arctic sea ice extent in May was about 4% below average, ranking fourth lowest on record for the month.

In the Antarctic, sea ice was around 9% below average, the seventh lowest for May, with particularly low coverage in the Bellingshausen Sea.