Why Overnight Heat, Not Peak Temperatures, Kills: Germany Warns of Compound Conditions

Germany's DWD weather service has flagged "compound heat conditions" during the ongoing European heatwave—the combination of high daytime temperatures with elevated overnight minima that prevents physiological recovery. This interaction, not single peak-temperature days, drives most heat-related mortality. As Europe faces repeated thermal extremes, understanding this mechanism matters: it shifts focus from headline numbers to accumulated thermal load across consecutive days, reshaping how public health systems should assess and prepare for prolonged events.