Carbon Brief obtained freedom-of-information data from all 10 NHS ambulance trusts in England showing that the June 2026 heatwave caused record demand. Four services saw their busiest-ever days for life-threatening emergencies, two saw record 999 call volumes, and on 26 June ambulances responded to 4,084 category 1 incidents, far above the usual summer average of around 2,500. The busiest days were concentrated between 23 and 27 June, when temperatures passed 37C in parts of England. The data shows heatwave demand matching or exceeding winter peaks and even Covid-era levels. With researchers estimating nearly 3,000 heat-related deaths in the UK this summer, the records add concrete evidence that climate change is straining health services and that heat resilience needs to be treated as a core part of NHS planning.
