The second warmest May on record saw warming oceans and atmosphere combine to drive weather extremes across multiple continents. | Photo Credit: PTI

May 2026 was the second warmest ever recorded globally for land and sea, the Copernicus Climate Change Service (C3S), implemented by the European Centre for Medium-Range Weather Forecasts (ECMWF), reported.

Global temperature

The ERA5 record shows May 2026 was the second warmest May on record, with an average surface air temperature of 15.81°C, or 0.55°C above the May 1991-2020 average, only surpassed by May 2024. This was 1.42°C higher than the estimated average for 1850–1900, before industrialisation.

Sea Surface Temperature

The average May 2026 SST (sea surface temperature) in the 60°S-60°N band was tied for the second warmest on record for the month at 20.90°C, behind May 2024 (20.93°C).

Heat extremes

Europe moved rapidly from much colder than average conditions this month to one of the hottest heatwaves recorded so early in the year in Western Europe.

The heatwave broke numerous records for the month, with France, the UK, Ireland and Portugal being especially hard hit. The event fits into the rapid warming trend in Europe and the longer-term trend of more frequent, more intense and earlier-season heatwaves.

There was also a contrast between dry and wet conditions. Much of western, central and eastern Europe – including Italy and Spain – was drier than average for the month.

By contrast, parts of northwest continental Europe, north Scandinavia, Finland, Türkiye and the Black Sea region were wetter than average, and there was widespread flooding in Türkiye, Bulgaria and Moldova.

Samantha Burgess, strategic lead for climate at ECMWF, commented: “May 2026 was the second warmest May on record globally, extending the exceptional global warmth, with near-record temperatures in both the atmosphere and the ocean.

In Europe, an unusually early and intense heatwave demonstrates how quickly climate extremes are becoming the new normal rather than the exception.”

SSTs continue to be very warm over a broad expanse of the tropical Pacific as the equatorial Pacific shifts towards El Nino conditions that are forecast to develop during the next few months, the report added.

Moisture divide

Outside Europe, wetter-than-average areas in May 2026 included northern and southeastern North America, regions of Asia north of the Indian subcontinent and in western China, as well as a region of Brazil, southern Africa and large parts of Australia.

In contrast, drier-than-average conditions were present over the central US, large portions of Central Asia, Madagascar, southwestern Australia and much of South America.

Extratropical regions that were wetter than average during March to May 2026 include parts of northern and eastern North America, Iraq and the Middle East, central Asia and China, and much of southern Africa and Australia. Drier than average conditions extended across the southern US, much of South America, Madagascar and southwestern Australia.

Published on June 10, 2026