Spain, under the most intense heat wave in history

In August 2025, Spain experienced the most intense heat wave in its meteorological history, according to the National Meteorological Agency (AEMET). The extreme phenomenon, which lasted 16 days, had dramatic consequences: tens of thousands of people affected, over a thousand deaths attributed to the heat and fires of huge proportions in the Iberian Peninsula.

• Extreme heat wave

The heat wave was more intense than the one in July 2022, the previous record. Average temperatures exceeded the usual values for that period by 4.6°C.

Between August 8 and 17, Spain recorded the highest temperatures since 1950, according to AEMET data. Since 1975, Spain has recorded 77 heat waves, but six of them had an anomaly of at least +4°C, five of which occurred after 2019. This acceleration confirms the trend of worsening extreme weather phenomena under the impact of climate change.

• Impact on health: over 1,100 deaths attributed to the heat wave

The Carlos III Health Institute (ISCIII), through the MoMo mortality monitoring system, estimates that 1,149 deaths are linked to the August heat wave.

In July 2025, the same system attributed around 1,600 deaths to the heat wave, over 50% more than in July 2024. MoMo does not establish direct causality, but correlates mortality with temperature deviations and historical series, being considered the best indicator of the impact of the heat wave on public health.

• Wildfires: 400,000 hectares destroyed in Spain and Portugal

The heat wave has fueled massive forest fires in the Iberian Peninsula. More than 400,000 hectares have burned in Spain and Portugal. The outbreaks have been amplified by drought and strong winds, turning into some of the most devastating fires in recent decades. The heat wave of August 2025 reconfirms the fragility of the Iberian Peninsula in the face of climate change. The intensification and increasing frequency of extreme phenomena - heat wave, drought, fires - are putting pressure on: public health systems, faced with thousands of additional deaths; the agricultural and forestry economy, affected by the loss of hundreds of thousands of hectares; urban infrastructures, unable to respond effectively to record temperatures.

The case of Spain and Portugal illustrates, more clearly than ever, that this climate crisis is no longer a projection of the future, but a present reality with huge human and economic costs.