How likely are extreme hot weather episodes in today’s UK climate?

In a study published in Weather, researchers estimated the current chances and characteristics of extreme hot episodes in the UK, and how they have changed over the last 6 decades.

The team found that temperatures several degrees above those recorded during the UK’s heatwave in July 2022 are plausible in today’s climate, with a simulated maximum of over 45°C (113°F). The likelihood of 40°C (104°F) is now over 20 times more likely than it was in the 1960s. Moreover, the chance of 40°C will likely continue to rise as the climate warms. The investigators estimate that there is approximately a 50% chance of again exceeding 40°C in the next 12 years.

Through multiple storylines of how temperatures could evolve through the summer season, they also found that prolonged heatwaves of over a month above 28°C (82°F) are possible in southeast England today. These storylines are valuable for modeling and stress testing.

“Our 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,” said corresponding author Gillian Kay, PhD, of the Met Office Hadley Centre.

URL upon publication: https://onlinelibrary.wiley.com/doi/10.1002/wea.7741