June Heatwave Linked to Estimated 20,000 Deaths Across Europe

A statistical model estimates that the heatwave from 22 to 28 June 2026 caused approximately 20,390 deaths across five European countries. The estimate includes 5,210 deaths in France, 4,543 in Germany, 3,163 in Spain, 2,709 in Italy, and 862 in the UK. These figures exceed the partial counts released so far by national health agencies.

The estimate was produced by correlating temperature and mortality data collected between 2015 and 2019, then applying that relationship to observed temperatures during the June period. Christopher Callahan at Indiana University led the analysis, which was posted as a preliminary report on Zenodo.

Officials have reported lower numbers. On 28 June, the World Health Organization stated that more than 1,300 excess deaths had been recorded so far, based largely on an incomplete French data set covering only hospital, long-term care, and some home deaths.

Other researchers have questioned whether the model overstates current risk. Dann Mitchell at the University of Bristol noted that 20,000 deaths in one week appears high and requires further review of the underlying calculations. Marcin Walkowiak at Poznań University of Medical Sciences said the relationship between heat and mortality may have weakened since 2015-2019 because of wider access to air conditioning and other adaptations.

His rough adjustment lowers the total to around 15,000. Callahan maintains that evidence for a substantial change in vulnerability is limited. He also noted that statistical models typically capture deaths where heat is not recorded on certificates, producing higher totals than direct reporting.

Raquel Nunes at the University of Warwick said the modeled figures will be refined over coming months as complete death records become available.