The strain is testing the adaptations that municipalities have put in place since a hallmark deadly heat wave in 2003. Repeated bouts of extreme heat led Western Europe to its warmest June on record, according to the European Union’s Copernicus Climate Change Service. The second half of the month had a heat wave that was so intense that it broke monthly and all-time temperature records across several countries. And heat’s damage isn’t limited to the time during a heat wave. Adaptation measures such as government heat action plans, cooling centers and early-warning systems have expanded since Europe’s catastrophic 2003 heat wave, which caused more than 60,000 excess deaths.