Spain enters first official heatwave of 2026 as temperatures hit 40C

Madrid baked under 40C on Sunday as Spain entered its first official heatwave of 2026, a stretch of extreme heat that immediately pushed 13 of the country’s 17 regions onto orange alert. The Basque Country was placed under Aemet’s highest red warning level, underscoring the public-safety risk as the heatwave was expected to last until Thursday.

The strain was visible in the capital’s streets and markets, where residents and tourists moved through one of the hottest days of the season. At El Rastro flea market, a Miami visitor identified as Haily San Cesario, a 22-year-old engineer, said she was dressed in white and carried a small electric fan everywhere she went, a snapshot of how quickly ordinary errands become difficult when temperatures surge.

Aemet had issued a special warning on Friday, June 20, for a heatwave affecting the Peninsula and the Balearic Islands from Sunday, June 21, through at least Wednesday, June 24. The agency’s commonly cited definition of a heatwave requires at least three consecutive days of exceptionally high temperatures at at least 10% of weather stations compared with local historical norms, which is why this episode was being treated as the first official heatwave rather than just a hot spell.

In parts of the Basque Country, inland areas of Bizkaia and Gipuzkoa were among the places under red alert because of the danger to public safety. Some forecasts had pointed to temperatures of around 42C in parts of Spain, with the most extreme projections suggesting readings could approach 45C, adding to concerns that dry vegetation and strong sun could sharpen wildfire risk.

Aemet has said it maintains a wide observation network and continuous monitoring of severe weather, with forecasts and warnings meant to support prevention and public safety measures. That warning system carries extra weight this summer: Aemet’s public climate summaries say 2025 was a record hot year in Spain and spring 2026 was the second warmest in the historical series, a backdrop that makes this early-season heat feel less like a one-off and more like a preview of a harsher summer ahead.