Spain’s summer of 2025 has cemented its place in the history books, ranking as one of the two hottest on record, nearly matching the historic summer of 2022. This extreme heat has been driven by extended periods of high temperatures, which have intensified wildfire risks and posed significant threats to public health across the country.
According to Spain's national meteorological agency, AEMET, the summer’s defining feature was a historic August heatwave that set a new record for intensity. With a temperature anomaly of 4.6°C, this event surpassed the previous record set in July 2022. The heatwave lasted 16 days, making the period from August 1st to 20th the warmest of its kind in Spain since at least 1961. The ten-day stretch from August 8th to 17th was the hottest ever recorded in the country.
The persistent heat has made 2025 the second-warmest year on record from January to August, trailing only 2024. This marks a concerning trend, as the last four years have all ranked among the hottest ever recorded, clearly surpassing previous historical benchmarks. While March was notably cold and May was near average, all other months of the year have been classified as warm, very warm, or extremely warm.
The Rising Threat of Climate Change
The trend of increasingly frequent and intense heatwaves is a direct consequence of climate change. AEMET data shows that the average temperature in Spain has risen by 1.69°C between 1961 and 2024. Scientific evidence confirms that heatwaves are becoming longer, more widespread, and more severe. While Spain has always experienced hot summers, recent years have seen an alarming increase in both daytime and nighttime temperatures.
The most intense heatwaves are becoming more frequent. The fact that five of the 20 warmest periods on record occurred during the recent August heatwave, and 15 have happened since 2022, underscores this trend. AEMET emphasised on social media that "The persistence of extreme heat intensifies its adversity," noting the severe impact on vulnerable populations and the escalating danger of wildfires.
A Glimpse into the Future
Climate projections suggest that by the middle of the 21st century, typical summers in the Mediterranean region could be approximately 2°C warmer than they were between 1981 and 2020. Alarmingly, the summers of 2022 and 2025 are already comparable to these mid-century conditions.
The data is undeniable: four of the five most intense heatwaves in Spain have occurred since 2019. This is not a coincidence but a clear indication of a long-term trend towards more extreme summers. While not every summer will be hotter than the last, the overall trajectory is clear and undeniable. This reality highlights the urgent need for both adaptation to and mitigation of climate change.