As Europe reels over a severe heatwave and the changing nature of climate change, Genie Godula is pleased to welcome Armel Castellan, Extreme Heat Services Technical Advisor at the World Meteorological Organization (WMO). Castellan suggests that extreme heat should no longer be understood as a temporary weather anomaly but as a structural public health, infrastructure, and societal challenge. His most striking observation is that today’s heat extremes are effectively the baseline from which even hotter futures will emerge. He reframes heatwaves not simply as episodes of discomfort but as cascading crises that affect human health, energy systems, housing, agriculture, water security, and emergency services simultaneously.