Western Europe and the Mediterranean gripped by major heatwaves in June
June 2025 was the third warmest June on record globally, as reported in the latest Climate Bulletin by the Copernicus Climate Change Service (C3S). Major heatwaves – intensified by high sea surface temperatures in the western Mediterranean Sea – led to ‘very strong heat stress’ in large parts of western and southern Europe.
In June 2025, western Europe as a whole saw its warmest June on record, with an average temperature of 20.49°C, surpassing the previous record for the month from 2003 by only 0.06°C. Two major heatwaves led to ‘very strong heat stress’ in large parts of western and southern Europe, with ‘extreme heat stress’ and feels-like temperatures reaching 48°C in parts of Portugal. Spain experienced its warmest June in 64 years while England reported the highest temperatures for June since data records began in 1884.
The average temperature over European land for June 2025 was 18.46°C, 1.10°C above the 1991-2020 average for June, making it the fifth-warmest June on record.
Outside of Europe, warmer-than-average temperatures were observed in a large part of the United States, northern Canada and central Asia, while record-breaking warmth was reported in Japan, some regions of China and many Korean cities. In contrast, southern South America experienced notably cold conditions in June, with record lows set in Argentina and Chile due to cold air circulation out of Antarctica.
Globally, June 2025 saw an average surface air temperature of 16.46°C, 0.47°C above the 1991–2020 average for June according to the ERA5 dataset. At +1.30°C above the pre-industrial baseline (1850–1900), it was the third month in the last 24 with a global temperature below 1.5°C.
Global-average surface air temperature anomalies relative to the 1850–1900 pre-industrial reference period for each June, all months, and running 12-month averages from 1979 to 2025. Use the grey and yellow toggles to change the temporal sampling. Data source: ERA5. Credit: C3S/ECMWF.
An exceptional marine heatwave in the western Mediterranean Sea in June led to the highest daily SST ever recorded in June for the region as a whole: 27.0°C (+3.7°C above average).
Record-breaking SSTs for the month of June were also observed in the western North Atlantic and western North Pacific, and warm anomalies continued in the western equatorial Pacific to the northeast of Australia.
June 2025 saw drier-than-average conditions in Europe’s western and southern regions as well as much of the UK and parts of southern Scandinavia and western Russia, with some records for the month broken at local scale. The dry conditions favoured the development of wildfires in Portugal and Türkiye.
Conversely, Iceland, Ireland, northern UK, Denmark, much of Fennoscandia, the Baltic states, Belarus and parts of Ukraine and Russia saw above-average precipitation. Heavy rainfall broke records at local scale in some regions, and in some cases, led to flash floods.
Beyond Europe, June 2025 brought drier-than-average conditions to eastern Africa, the Arabian Peninsula, central Asia, east China, Japan, Australia, southern Africa and much of southern South America. In northern USA and Canada, dry conditions also contributed to wildfires.
Wetter-than-average conditions were seen in the southern USA, northern Mexico, northern and southwestern Asia, parts of China, northern Australia and southern Brazil. Across Asia and in Brazil, flooding and associated damage resulted from heavy precipitation.
Arctic sea ice extent was 6% below the 1991–2020 average for June, marking the second lowest June extent in the 47-year satellite record. From 10 June onward, daily sea ice extent values set record lows for the season, with 9.6 million km² at month’s end—the lowest on record for that date.
Time series of monthly mean Arctic sea ice extent anomalies for all June months from 1979 to 2025. The anomalies are expressed as a percentage of the June average for the period 1991-2020. Data source: EUMETSAT OSI SAF Sea Ice Index v2.2. Credit: C3S/ECMWF/EUMETSAT.
Antarctic sea ice in June 2025 was 9% below the 1991–2020 average at 12.6 million km², the third-lowest June extent on record—exceeded only by the previous two years.
Every month the Copernicus Climate Change Service provides an update on temperatures, hydrology and sea ice, showing the current condition of the climate. The Climate Bulletins include charts and maps with the evolution of key climate change indicators, mainly based on C3S’s reanalysis dataset ERA5.