Cold weather linked to an estimated 270 deaths in the South West during winter 2024/25

The UK Health Security Agency (UKHSA) has published its first Cold Mortality Monitoring Report, revealing that an estimated 270 deaths in the South West were associated with cold weather during winter 2024 to 2025.

The South West was among the regions where statistically significant cold-associated mortality was recorded across three cold episodes between November 2024 and January 2025.

The most severe cold spell, lasting six days in January 2025, accounted for an estimated 173 deaths in the South West alone. Amber Cold Health Alerts were issued across the region during this period. Earlier, shorter episodes in November and early January were associated with 44 and 53 deaths, respectively, in the South West.

Nationally, 2,544 deaths were linked to cold weather across England during the same period.

Key national findings from the report include:

• Older people were most affected, with the risk rising steeply with age, especially in those aged 85 and over
• Men had a higher number of cold-associated deaths (1,439) than women (1,117)
• Circulatory diseases caused the highest number of cold-related deaths, with 834 deaths linked to conditions such as heart disease
• Most deaths (975) happened in hospitals, although the increase in risk during cold weather was greater for people in care homes and those who died at home

The report found that mortality peaks around five days after cold weather and remains elevated for up to nine days. Heart-related deaths tend to increase several days after cold exposure, while respiratory and infection-related deaths show longer delays.

To understand the health impact of cold weather, UKHSA analyses daily death registrations alongside Met Office temperature data. UKHSA used a statistical model that shows how the risk of death increases as temperatures fall, and how these effects can build up over several days. This helps us to estimate the number of deaths linked to specific cold spells, rather than relying on death certificates, which do not record “cold” as a cause.

These estimates form a key part of wider winter health surveillance. They sit alongside monitoring of flu, COVID-19, RSV, norovirus and other seasonal pressures, helping to ensure that Cold Weather Alerts and preparedness planning reflect the real health risks faced by vulnerable groups.

UKHSA’s episode-based method provides an up-to-date picture of how recent cold weather has affected people’s health under current population and health system pressures, complementing the Office for National Statistics’ (ONS) long-term analyses that estimate the average impact of cold weather over many decades. Because UKHSA focuses on specific recent winters and the ONS looks at long-term trends, the figures are not directly comparable, but together they give a fuller picture of how cold weather affects health in England.

Elizabeth Smout, Interim Regional Deputy Director of Health Protection at UKHSA South West, said:

"Cold weather remains a serious and preventable risk to public health here in the South West, and today's report underlines just how important it is that we all take action during cold spells.

"This report provides important new evidence showing that even short periods of cold can lead to significant increases in mortality, often days or weeks after the temperature drops. Understanding who is most affected helps us better target winter preparedness and support vulnerable groups across the South West.

"With the current cold snap expected to last at least until this Friday, according to Met Office forecasts, we are urging people to check in on friends, family and neighbours who may be more vulnerable to the cold and make sure that they are able to keep themselves warm while this period of cold lasts.

“We know that prolonged exposure to low temperatures can have a severe impact on people's health, especially if they are older or have serious health conditions.”

Population groups most at risk from cold weather include:

• people aged 65 years and over
• people with cardiovascular or respiratory conditions
• people with dementia
• people living in poorly insulated homes or experiencing fuel poverty

When comparing recent winters with the previous five-year period, the findings suggest people may now be more vulnerable to cold, with the risk of death rising more sharply as temperatures drop. This is likely to be the result of a combination of factors, including the ageing population and burden of disease.

While further research over longer time periods is needed to confirm whether this represents a sustained shift, these findings suggest that vulnerability to cold may be increasing even if average winter temperatures are not becoming colder. Factors such as home insulation and heating, access to healthcare, vaccination uptake, and awareness of cold-weather risks can all influence cold-associated mortality.

UKHSA has published guidance for professionals protecting vulnerable people and for the public on staying safe during periods of cold weather.

The full Cold Mortality Monitoring Report is available on GOV.UK. This report complements the annual heat mortality monitoring reports published by UKHSA, and both contribute to the evidence base underpinning the Adverse Weather and Health Plan for England.