1295. Third Warmest June on Record – Heatwave in Europe as Extreme Temperatures Continue in both Hemispheres

According to the Copernicus Climate Change Service (C3S), June 2025 was the third warmest June on record, with surface temperatures averaging 16.46°C, 1.30°C higher than the estimated average temperature from 1850-1900, used to define pre-industrial levels. This is 0.47°C higher than the average June temperature from 1991-2020, 0.20°C lower than the record-breaking June of 2024, and 0.06°C lower than the second-warmest June of 2023.

Across Western Europe, the average temperature was 20.49°C, the hottest June on record, 2.81°C higher than the 1991-2020 average and 0.06°C above the previous June 2003 record (20.43°C). Two major heat waves in mid- and late June 2025 affected large areas of Western and Southern Europe. Much of the region experienced "very strong heat stress" conditions, with temperatures above 38°C, and parts of Portugal experienced "extreme heat stress" conditions, with temperatures reaching around 48°C.

Outside Europe, the United States, northern Canada, Central Asia, East Asia, and Western Antarctica experienced the highest above-normal temperatures. Meanwhile, southern South America experienced the lowest below-normal temperatures, with record-cold temperatures recorded in Argentina and Chile. Temperatures were also below-normal in India and Eastern Antarctica.

Contributor: IIYAMA Miyuki, Information Program