Despite relentless record-breaking temperatures and what feels like no respite at all, some 'chilly' Brits are saying they don't feel anywhere as hot as when the heatwave started. As some people claim they are even starting to feel cold despite the mercury remaining high, scientists have explained the reasons why.
Heat Acclimatisation: How Bodies Adapt
Experts say that following weeks of sustained heat, the bodies of many have started adapting to cope, with some claiming they hardly notice the blazing heat. Social media users have sparked a debate, with some saying they need extra layers of clothing in the middle of the day after they started to feel cold this week. One TikToker asked: "Is it just me, or is 24, 25, and 26°C starting to feel a bit chilly? I left the house in my trousers and jacket today. Why am I feeling cold?"
Another posted: "Alexa told me its highs of 29°C today I immediately thought ah that will be nice its cool today. Got a bbq Saturday, it's gonna be 25 and I'm wondering if they're gonna call it off."
Dr Alex Lloyd, a Senior Lecturer in Human Factors & Environmental Physiology at Loughborough University, explained that it takes just two weeks for our bodies to get used to the searing heat. "Heat acclimatisation is a well-established physiological process by which the body 'learns' to better tolerate high temperatures through repeated exposure," he told MailOnline. "After a week or more away from heat, some of the adaptation can start to fade, so people may need to acclimatise again."
Physiological Changes and Health Risks
According to the Sports Science Institute, heat acclimatisation involves exposing the body to hot conditions over seven to 14 days to "induce physiological adaptations." These include increased blood plasma volume, an earlier onset of sweating, and a reduced heart rate, which significantly lower cardiovascular strain. It also decreases body temperature, reducing the risk of heat-related illnesses. "Biological adaptations include integrated thermoregulatory, cardiovascular, fluid-electrolyte, metabolic and molecular responses," they say.
However, Dr Lloyd warned that prolonged heat exposure can cause health problems including heat exhaustion, muscle breakdown, and heat stroke.
Met Office Forecast: Cooling Off
The Met Office expects temperatures in the UK to start cooling off by the end of this week as the third heatwave of 2026 comes to an end. Three scorching spells so far this year have brought record-busting temperatures, leading to an increase in fires and ill health effects for many. Meteorologist Aidan McGivern explained that a shift in high pressure should mean peak temperatures drop off on Saturday and Sunday. "High pressure, by the end of this week, is drifting towards the north-west, and that's going to allow something a little fresher to recirculate around the high pressure," he said. "Still above average temperatures for many, but by the time we get to Sunday those temperature anomalies are reducing. So things are gradually cooling off for the rest of the week. It's not going to be cold, neither is it going to be unsettled, but the high pressure is drifting into a position to allow something less hot to circulate around it."
He added that by Saturday and Sunday, temperatures will be in the mid to high-20s rather than the low-30s, with the highest temperatures expected in Wales and the south-west, and the lowest in the east and north.
