Portugal braces for near‑40 °C heat wave as subtropical air mass arrives

A subtropical air mass is expected to reach mainland Portugal on Wednesday, June 10, triggering a rapid rise in temperatures across the country. Forecasts show maximums of around 34 °C in the central and southern interior on Wednesday, with the northern region warming to about 28 °C. By Thursday, the Vale do Douro could see 35 °C, while Braga and Vila Real may reach 32 °C and 30 °C respectively.

Friday, June 12, is projected to be the hottest day, with temperatures nearing 40 °C in the Douro and Tagus valleys and in southern locales such as Alcácer do Sal and Grândola. District capitals in the north will stay cooler, around 27 °C in Aveiro and Viana do Castelo, while the southern interior may hit 36 °C. Saturday brings a slight relief in the northwest and a chance of rain and thunderstorms in the north.

Health authorities advise extra precautions for the elderly, children, and those with chronic conditions: stay hydrated, limit exposure during peak heat, and seek cooler indoor spaces. The heat also raises fire risk, prompting restrictions on open flames, motor‑powered garden tools, and outdoor grilling in vulnerable areas.