UK temperatures of 45C may be possible in current climate, Met Office says

The Guardian

18-06-2025

The UK has a 50/50 chance of seeing temperatures soar to 40C again in the next 12 years as the risk of extreme heat rises with the climate emergency, the Met Office has said.
The meteorological experts also warned that far higher temperatures of 45C (113F) or more 'may be possible' in today's climate, while heatwaves could go on for a month or more.
Temperatures hit 40C in the UK for the first time on record amid the heatwave and drought summer of 2022, peaking at 40.3C in Coningsby in Lincolnshire on 19 July, outstripping the previous top temperature of 38.7C recorded in Cambridge three years earlier.
Fire brigades in London, Leicestershire and South Yorkshire declared major incidents as dozens of fires broke out and ripped through houses, schools, churches and farmland, while there was widespread disruption to transport and power systems.
More than 1,000 excess deaths among older people were recorded around the four-day peak of the heatwave, with more than 3,000 heat-related deaths in England over the summer of that year.
Analysis by the Met Office, using global models to create a large number of climate outcomes in current conditions, shows the risk of 40C temperatures in the UK has been rapidly increasing.
A study published in the journal Weather shows that the chance of temperatures hitting 40C is more than 20 times more likely than it was in the 1960s, and has almost trebled since the year 2000.
With the climate crisis pushing up temperatures, the chances of exceeding 40C were continuing to increase, with a 50/50 chance of a day hitting that threshold again in the next 12 years, the Met Office said.
Temperatures several degrees higher than the July 2022 record – up to a maximum of 46.6C – were also 'plausible'.
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Dr Gillian Kay, a senior scientist at the Met Office and lead author of the study, said: 'The chance of exceeding 40C has been rapidly increasing, and it is now over 20 times more likely than it was in the 1960s. Because our climate continues to warm, we can expect the chance to keep rising. We estimate a 50/50 chance of seeing a 40C day again in the next 12 years. We also found that temperatures several degrees higher than we saw in July 2022 are possible in today's climate.'
The study also looked at heatwaves, and found that 'much more severe' extremes could occur in the current climate.
The climate model shows up to two-thirds of summer days could be above the heatwave threshold of 28C in south-east England, with more than a month in continuous heatwave.
Twelve consecutive days above 35C is also possible, the study says. Met Office experts said the findings showed the need to prepare and plan for the impact of rising temperatures and extreme heat.
Dr Nick Dunstone, a Met Office science fellow and co-author of the study, said: 'The well-known hot summer of 1976 had more than a fortnight above 28C, which is a key heatwave threshold in south-east England.
'Our study finds that in today's climate such conditions could persist for a month or more. These findings highlight the need to prepare and plan for the impacts of rising temperatures now, so we can better protect public health, infrastructure and the environment from the growing threat of extreme heat.'