The UK Met Office extended an amber extreme heat warning for London, East Anglia, southeastern England, and parts of the East Midlands on Saturday, June 27, 2026.
The warning remains in place until Sunday morning after temperatures peaked at 37.3 degrees Celsius in Santon Downham, Suffolk.
That reading surpassed the previous June record of 37.1 degrees Celsius set earlier the same day in Cavendish.
Several hospitals declared critical incidents due to the intense heat, according to ITV News.
University Hospital Southampton canceled multiple planned operations and outpatient appointments, alongside similar emergency declarations at facilities in Portsmouth and Norfolk.
Weather Shift Expected
Met Office chief forecaster Andy Page said fresher conditions were slowly moving eastward across the country.
"The UK is seeing a gradual shift in conditions over the weekend, with those to the southeast of England retaining the warmth the longest," Page said.
He noted that an amber extreme heat warning remains in force through much of Saturday, though peaks are more likely to be in the low 30s Celsius.
Public health officials urged people to take precautions as large crowds gathered for outdoor events.
Craig Harman, chief operating officer of the country’s largest ambulance service, advised drinking water even when not thirsty and staying out of the sun during the hottest parts of the day.
"Particularly not exercising outside and putting your body under additional heat and strain," Harman said.
Environmental advocacy groups linked the unprecedented western European "heat-dome" to human-driven climate change.
Julie Henri, senior climate advocacy advisor at WaterAid, said the record-breaking heat offers a "terrifying glimpse of what could become the new normal."
Henri emphasized that reliable infrastructure is necessary to handle extreme weather anomalies globally.
"While we feel the heat and its impacts in the UK, this has been the reality for communities on the frontlines of climate change for many years," she said.
Water availability remains the primary concern for long-term climate resilience programs, Henri added.
Medical entomologists also warned of increased risk of insect-borne illnesses due to the current weather conditions.
Dr Mojca Kristan, assistant professor in medical entomology at the London School of Hygiene and Tropical Medicine, advised using insect repellent and covering skin with long sleeves.
"Wear socks in the evening as mosquitoes like biting around ankles," Kristan said.
