Spain is facing its first major heatwave of the summer, with meteorological data confirming record June temperatures. The Agencia Estatal de Meteorología (Aemet) forecasts the hottest June days since at least 1950 this week. The heatwave began on Sunday, June 21, after an unusually warm June and a late May marked by extreme temperatures across much of Spain and Western Europe. Mainland Spain’s daily-average temperature reached 28.08°C on Monday and 28.17°C on Tuesday, the highest June daily averages in records dating back to at least 1950. Average minimum temperatures were also exceptionally high, at 20.14°C and 19.81°C on those days, leaving little relief from the heat overnight.
Authorities have activated health alerts in 86 isoclimatic zones, covering 5,266 municipalities and nearly 21.9 million residents, about 46% of Spain’s population. The Ministry of Health has warned regional and local governments, urging them to inform the public about the risks. In parts of northern Spain, including Cantabria and the Basque Country, temperatures exceeded 40°C in areas less accustomed to the country’s most severe heat. Most alerts had been lifted by Thursday, though yellow-level warnings remained in parts of the north. The recent temperature spike has already proved deadly: the late-May heat event resulted in 101 deaths, the highest toll for that month since the MoMo monitoring system began in 2015. Separately, MoMo estimated 212 excess deaths associated with the June heatwave between Sunday and Wednesday. The system compares observed deaths with expected mortality based on historical patterns and meteorological data. Its early estimate is not a clinical determination that heat directly caused each death. The corresponding four-day period in 2025 recorded 98 excess deaths.
The June heatwave affected mainland Spain and the Balearic Islands as part of a wider episode gripping much of Europe, especially France. The Canary Islands were largely untouched. Aemet says heatwaves are now arriving earlier each year, a trend linked to climate change. Between 1975 and 2000, mainland Spain recorded only two June heatwaves. From 2000 to 2025, the number rose to ten. The heatwave season now starts about four days earlier per decade, extending periods of extreme heat. High overnight temperatures add to the danger: with little respite after daytime exposure, the body has less chance to recover from heat stress.
Aemet defines heatwaves as periods of at least three consecutive days when at least 10% of reference weather stations record maximum temperatures above the 95th percentile for July and August. Analysis of the past 50 years shows that 40% of all heatwaves in mainland Spain have occurred since 2015. They are also lasting longer. In the last decade, the average heatwave lasted 7.2 days, compared with five days in the previous four decades, a 30% increase.
These extreme events are part of a broader trend of global warming. Carlo Buontempo, director of the Copernicus Climate Change Service, says the past 11 years have been the warmest on record worldwide. In Spain, the last four years have been the hottest since records began, and the national average temperature has risen by 1.75 degrees Celsius since 1961. Human-driven greenhouse gas emissions, particularly from fossil fuel combustion, are the basic cause of these rapid changes.
Research published in Nature in September examined 213 historical heatwaves worldwide between 2000 and 2023. The study found that global warming intensified every one, and that a quarter would have been nearly impossible without current temperature levels. In Spain, researchers analyzed eight major heatwaves, including the extreme summer of 2022. They found that such events would not have occurred without the current degree of warming.
Last summer tied with 2022 as Spain’s hottest on record and brought three severe heatwaves. The final one lasted 16 days and contributed to devastating wildfires in August, which destroyed over 300,000 hectares, the worst such damage since the 1990s. Earlier heatwaves had already dried out vegetation, setting the stage for the fires. Experts are watching the end of June 2026 to gauge the potential severity of this year’s wildfire season, though several factors make fire activity difficult to predict. Full-season figures later placed the June episode in a wider national context: Aemet data for peninsular Spain showed a summer mean temperature of 24.5°C, 2.4°C above the 1991-2020 reference average and 0.3°C higher than the previous record set in 2025. The season’s mean precipitation was 39.6 millimetres, while some locations recorded 44.4°C.
A separate analysis by researchers at Imperial College London and the London School of Hygiene & Tropical Medicine estimated 6,824 heat-related deaths in Spain between June and August 2026. It attributed 5,227, about 77%, to human-caused climate change. This modeled seasonal estimate uses a different method from MoMo’s short-term excess-mortality monitoring. The researchers also estimated that Spain experienced 61 heatwave days during the summer. Their estimate was below the roughly 13,000 heat-related deaths attributed to Spain in 2003.
Across Europe, a related analysis covered 854 urban areas in 30 countries: the EU-27, the United Kingdom, Norway and Switzerland. Researchers estimated that fossil-fuel-driven climate change caused about two-thirds of European heat deaths during summer 2026. Spain ranked among the five most affected countries, after Italy and France and ahead of Germany and the United Kingdom. The analysis flagged early-season heat as a particular risk because people may be less physiologically acclimatized to extreme temperatures.
Globally, 2024 is currently the hottest year on record, but the developing El Niño phenomenon could soon push temperatures higher and displace it. Buontempo says another global temperature record is likely within the next 12 to 18 months, possibly as soon as 2026 or 2027.
Spain’s geography and climate increase its vulnerability to heatwaves. Urban population concentration and an aging population raise health risks during extreme heat; many people also work outdoors. The government’s alert system, coordinated through Aemet and the Ministry of Health, aims to reduce those risks by providing timely information and activating emergency protocols. As heatwaves grow more frequent and intense, Spanish cities and regions are increasingly turning to adaptation measures such as urban cooling strategies and public health campaigns.
