The UK has recorded its highest ever May temperature for the second consecutive day, with thermometers reaching 35.1°C at Heathrow and Kew Gardens in London, the Met Office confirmed.
The latest record followed the country's provisional hottest spring temperature of 34.8°C in Kew Gardens on Monday, which surpassed the previous May peak of 32.8°C set in 1922.
The Met Office issued a yellow weather warning for thunderstorms across England on Tuesday, cautioning that isolated storms with lightning, hail, and gusty winds could impact large areas from Bath and Reading to Lincoln and Sheffield between 3'pm and 10'pm.
While many regions remained hot and sunny, forecasts warned of potential flash flooding, with up to 30mm of rainfall possible in an hour in some locations.
Earlier Tuesday, the amber health warning was extended by 24 hours for multiple regions in England, including the southwest, southeast, London, the East and West Midlands, and the west of England. The UK Health Security Agency maintained amber alerts until 5'pm Thursday, with yellow alerts in place for the northwest and northeast. The southwest warning was upgraded from yellow to amber.
The National Fire Chiefs Council issued a water safety warning following several fatalities over the bank holiday weekend, including four teenagers.
A 13-year-old boy died Monday in a West Yorkshire reservoir, while South Yorkshire police recovered the body of a boy from a park in Rotherham early Tuesday, the same day a teenage girl was found dead at a Warwickshire water park.
In Lincolnshire, divers located the body of 15-year-old Declan Sawyer in a Lincoln lake, and in Cornwall, a man in his 60s died attempting to rescue family members caught in rough seas at Tregirls beach in Padstow.
Lancashire police continued searching Tuesday for a boy who struggled while swimming in the Ribble Valley.
The country experienced a “tropical night” Monday, with temperatures not dropping below 20°C. Kenley airfield in south London recorded an overnight low of 21.3°C.
Many areas of England and Wales reached heatwave thresholds Tuesday, with some regions experiencing five consecutive days of such conditions, according to Met Office senior meteorologist Becky Mitchell.
To qualify as a heatwave, temperatures must remain at or above specific thresholds for three consecutive days. The highest threshold, 28°C, applies to London and parts of Cambridgeshire.
May also recorded an unprecedented temperature range, with Dr Stephen Burt of the University of Reading noting a swing from -0.1°C (air frost) on May 12 to 32.8°C, a difference of 32.9°C. This exceeded the previous May record of 32.8°C set in 1944.
Climate experts linked the extreme weather to global warming. Friederike Otto, a professor of climate science at Imperial College London, stated: “This record-breaking heat bears the unmistakable signature of climate change. Temperatures of this magnitude were once rare even during peak summer months. Reaching 35°C in the UK during spring is astonishing, yet the science is clear—climate change intensifies heatwaves, making them hotter, longer, and more frequent.”
“The climate we face today is fundamentally different from the one we grew up in, and our buildings and infrastructure are terribly unprepared for what lies ahead.”
Temperatures are expected to decline midweek, though sunny conditions will persist in many areas, with some regions experiencing highs in the late 20s. Eastern areas may see temperatures drop by approximately 10'C due to a strengthening easterly wind.
If validated, May's new record means seven months have exceeded previous temperature benchmarks since 2003.
A prior Met Office study indicated that breaking the May record is now roughly three times more likely in today's climate compared to pre-industrial conditions, transforming a once-in-a-century event into a once-in-33-year occurrence.