Western Europe Sees Hottest June on Record

Western Europe recorded its hottest June on record this year, with average temperatures reaching 20.74°C (69.3°F), exceeding the 1991-2020 average by more than 3°C. The heatwave caused widespread disruption, including power supply issues and school closures. National authorities reported over 4,700 excess deaths in France, Belgium, Spain, and the Netherlands during this period.

The intense heat fueled wildfires across Iberia and southern France. According to Los Angeles Times, hundreds of firefighters battled a deadly wildfire in BÉJAR, Spain that killed at least 12 people. The fire scorched about 25 square miles of forest and farmland, an area roughly equivalent to Manhattan. Most victims were believed to be foreign nationals who ignored shelter-in-place instructions.

The Copernicus Climate Change Service noted that Western Europe has now suffered three intense heatwaves in as many months. Samantha Burgess from the European Centre for Medium-Range Weather Forecasts emphasized how these events underscore profound climate changes, leading to increasingly intense heatwaves and growing risks for people and ecosystems.

Globally, June 2026 saw record-high sea surface temperatures, partly driven by a strong El Niño weather pattern in the Pacific Ocean. The average sea surface temperature across oceans outside the polar regions reached 20.86°C (69.55°F), according to Copernicus. While El Niño did not contribute to Europe's June heatwave, climate change played a significant role in worsening extreme temperatures.

The Mediterranean experienced its own record-breaking marine heatwave, with the continent’s Atlantic coasts also hit by hot spells, putting ecosystems at risk. High humidity levels were one of the reasons the June heatwave was so intense. The World Meteorological Organization reported that greenhouse gas emissions have raised the planet's average temperature by about 1.4°C above pre-industrial levels.

More than two-thirds of Europeans – 410 million people – endured temperatures topping 35°C (95°F) during the June heatwave, according to an analysis by AFP. The heat also affected other regions, including Southern California and portions of the Midwest, South, and Northeast in the U.S.

To prepare for more periods of extreme heat, California has launched CalHeatScore, an 'extreme heat scoring system' with five numerical levels, along with a dashboard posting heat-related emergency room visits in near-real time. Nationally, extreme heat is the leading cause of weather-related deaths in the United States.