Do summer heatwaves lead to a spike in deaths?

When the UK’s hottest day on record was recorded this summer, an increase in deaths followed.

Office for National Statistics look at how hot weather affects the number of deaths that occur.

England and Wales have seen some of the hottest summers in recent years. The mean temperature for the meteorological summer (June to August) was 17.0 degrees Celsius in 2018 and 16.1 degrees in 2019. Back in 1919, the mean summer temperature was only 14.3 degrees.

With the unusually hot weather come media headlines, warning people against the dangers of the heatwave and how the hot temperatures are leading to an increasing number of deaths – “killer heatwave” stories are not uncommon. But are those headlines backed up by the data? The chart shows provisional data on the impact heat has had on mortality this summer.

The number of deaths increased around the same time as the hottest day on record. However, the ONS said it is too early to tell how many of the deaths can be attributed to the heat.