Scorching heat to grip Spain this weekend as temperatures soar to a blistering 45 degrees Celsius.
Spain is preparing for its second heatwave of the summer, with temperatures set to soar to around 42°C in southern regions from August 3 to August 7 [1]. This intense heatwave is forecast to develop as a high-pressure system moves eastward over Portugal and Spain, bringing further heatwave risks, particularly to western Spain [1].
The upcoming heatwave is expected to bring a series of challenges, including heightened health risks for populations due to extreme temperatures and increased strain on energy systems. Previous heatwaves in Spain this year have significantly increased electricity demand by up to 14%, contributing to sharp electricity price rises and power system stresses [2]. Given the higher projected temperatures, similar or greater disruptions to power grids and health impacts are likely during this heatwave [2].
Southern Spain will experience the highest temperatures, with daily highs near 42°C, while central and western areas will also face significant heat elevation [1]. The prolonged exposure to high temperatures, with heat seasons lasting from late May to mid-September in cities like Madrid, adds to the risks [3]. The heatwave's progression eastward may also cause unseasonably high temperatures in other European countries following Spain's peak [1].
The extreme heat is set to be intensified by a strong ridge in the mid-levels of the atmosphere, which will promote atmospheric stability and descending air, enhancing surface heating [1]. In parts of Andalusia and Extremadura, temperatures could reach up to 45°C [1]. The heatwave could last until Wednesday, August 7, with some respite expected in the north of the peninsula next Tuesday [1]. However, uncertainty about the total duration of the episode is high [1].
The heatwave is expected to result in tropical nights, where night-time temperatures do not drop below 20°C, and equatorial nights on the Mediterranean coasts and central and southern areas [1]. The Guadiana and Guadalquivir valleys will be especially impacted, with a very high likelihood of temperatures surpassing 42°C [1]. The most extreme heat is expected on August 4 and 5, with August 5 likely to be the peak of this heatwave episode [1].
The heatwave is also expected to intensify the effect of urban heat islands, making it difficult to rest at night, especially in metropolitan areas [1]. The extreme heat could persist beyond Wednesday, potentially continuing into the following week, especially in the south [1].
Health officials are urging people to take precautions, particularly during the hottest hours of the day, and to stay hydrated. The heatwave could have significant impacts on health, particularly heat stress and difficulty resting at night, especially in urban areas [1].
References:
[1] Met Office. (2025). Spain to experience second heatwave of summer 2025. Retrieved from https://www.metoffice.gov.uk/climate/uk/interesting/articles/spain-heatwave-2025
[2] Euractiv. (2025). Spain's electricity demand surges during heatwaves, causing power system stresses. Retrieved from https://www.euractiv.com/section/energy-environment/news/spains-electricity-demand-surges-during-heatwaves-causing-power-system-stresses/
[3] AEMET. (2025). Heat season in Madrid lasts from late May to mid-September. Retrieved from https://www.aemet.es/es/temas/clima-y-ambiente/calentamiento-global/calentamiento-global-en-espana/calentamiento-global-en-madrid-2025
- In response to the upcoming heatwave, environmental scientists are closely monitoring the impact on both human health and energy systems, recalling prior heatwaves this year that increased electricity demand by up to 14% and caused power system stresses.
- The unfolding heatwave, expected to reach parts of Spain with temperatures up to 45°C, is believed to be exacerbated by climate change, as it coincides with the prolonged heat season and the development of tropical nights and equatorial nights in certain regions.
