Photo: Wildfire in northwestern Spain in August 2025 (World Central Kitchen, www.flickr.com)

The heatwave in Spain was the most intense since records began, lasting about two weeks and being 4.6 °C hotter than the average heatwave in this region. The extreme weather conditions are now 40 times more likely because of climate change, according to an analysis by World Weather Attribution.

In the summer of 2025, wildfires burned around 1% of the surface of Spain and Portugal. The fires occurred during a 16-day heatwave, the most intense since records began. So far, around 380,000 hectares (ha) have burned across Spain since the start of the year, and 260,000 ha in neighbouring Portugal. These fires together represent two-thirds of the one million hectares of land that have burned in Europe so far in 2025.

The area burned in Spain was not the largest in recent history. It ranked fifth. The year with the largest burned area was 1985 with nearly 485,000 ha. The year with the largest burned area in Portugal – an all-time record for this country most affected by fires in Europe – was 2017, with 540,000 ha.

The heatwave in Spain was the most intense since records began, lasting about two weeks and being 4.6 °C hotter than the average heatwave in this region. The extreme weather conditions are now 40 times more likely because of climate change. An extreme heatwave like this now occurs about once every 15 years, compared to once every 500 years without climate change. The increase in likelihood of the intensity of the observed ten hottest days is even more dramatic. This intensity has increased by just over 3°C – a heat event that now occurs once every 13 years, but a once-in-2500 year event without climate change.

Besides extreme weather conditions, rural depopulation is also a major cause of these extremely large wildfires. This has led to forest land not being managed, resulting in high fuel loads.

Source: World Weather Attribution, downloaded 4 September 2025.