Paris May Hit 40°C in June for First Time, Signaling Earlier Peak Heat

France's second heatwave of 2026 could push Paris above 40°C this week—a June threshold never breached in recorded history. Temperatures across 35 departments hit red alert status as forecasters warn of peaks near 42°C. The shift matters because extreme heat has historically peaked in late July; cresting 40°C in June signals a narrowing seasonal window, stressing infrastructure designed for older temperature patterns.