A rapid attribution study by World Weather Attribution found that the June European heatwave, with daytime temperatures exceeding 40°C in multiple locations, would have been virtually impossible without human-caused climate change. The analysis compared the event to 1976 and 2003 baselines and concluded that daytime peaks were 3.5°C and 2°C hotter, respectively, than they would have been in those earlier climates. One claim regarding a 200-fold increase in likelihood was internally disputed within source reporting.