Heat summary – heat mortality monitoring reports
Source: gov.uk (2025-04-03)

Since 2016, annual reports on the surveillance of mortality during periods of heatwave have been published.

CCHS navigation menu: CCHS homepage (https://www.gov.uk/government/organisations/the-centre-for-climate-health-security)Topic: weather-related hazards (https://www.gov.uk/government/collections/climate-related-hazards) Hazard: all weather-related hazards (https://www.gov.uk/government/collections/all-climate-related-hazards), heat (https://www.gov.uk/government/collections/heat)

Key resources for heat mortality monitoring reports:
- Heat summary – all heat mortality monitoring reports
- Report for 2024 (https://www.gov.uk/government/statistics/heat-mortality-monitoring-report-england-2024)
- Reports for 2020 to 2023 (https://www.gov.uk/government/publications/heat-mortality-monitoring-reports)
- Reports for 2016 to 2019 (https://webarchive.nationalarchives.gov.uk/ukgwa/20201108081248/https://www.gov.uk/government/publications/phe-heatwave-mortality-monitoring)
More content:
- All climate-related hazard surveillance reports (https://www.gov.uk/guidance/surveillance-reports)
Summary

The UK Health Security Agency (UKHSA) (and previously Public Health England) has published annual heat mortality monitoring reports each year since 2016. The reports give estimates of heat-associated deaths during heat episodes in each summer. Over this period, we have observed a general trend of increasing heat-episode days and increasing heat-associated deaths.

Figure 1. Heat-associated deaths (blue bars) and number of days that met the UKHSA definition of heat episode (red line), England, 2016 to 2024

The year 2022, which saw the highest recorded temperature in England at 40.3°C, had the highest number of heat-associated deaths since recording began of 2,985 deaths (95% Confidence Interval: 2,258 to 3,712) over 5 heat episodes.

The estimates for each year can be found in the annual reports, published by UKHSA for summer 2024 as official statistics (https://www.gov.uk/government/statistics/heat-mortality-monitoring-report-england-2024) and previously for summers 2016 to 2023 as research and analysis (https://www.gov.uk/government/publications/heat-mortality-monitoring-reports). Estimates are broken down by region and age group.

Analysis of heat-associated mortality is used by UKHSA to monitor progress on the goals of the Adverse Weather and Health Plan (https://www.gov.uk/guidance/adverse-weather-and-health-plan) and to inform continuous improvement to the Weather-Health Alerting system (https://www.gov.uk/guidance/weather-health-alerting-wha-system).

Developments to the reporting

For the 2023 report, we added a breakdown of heat-associated deaths by sex and an estimate of premature mortality associated with heat, measured in years of life lost. In the latest 2024 report, we added new breakdowns by Local Resilience Forum area, place of death and cause of death. Additionally, the 2024 report has been published as official statistics for the first time, demonstrating that UKHSA heat mortality monitoring statistics are produced in line with the standards of trustworthiness, quality and value in the Code of Practice for Statistics (https://code.statisticsauthority.gov.uk/).

For the 2022 report onwards, we have reported modelled heat-associated mortality as well as observed heat-associated mortality. The modelled figures are an estimate of the number of deaths expected in each heat episode, based on the historic temperature-mortality relationship in England in the last 5 years. Comparing observed mortality with the modelled predictions helps us to understand the range of factors, beyond temperatures, that can affect mortality during heat episodes.

Further information on mortality statistics

Measuring excess mortality: a guide to the main reports (https://www.gov.uk/guidance/measuring-excess-mortality-a-guide-to-the-main-reports) is a guide to the major publications related to excess deaths in the UK, who produces them and links to the methods and analysis.