London Ambulance chief warns people to ‘drink responsibly’ as sweltering heat continues
The LAS has seen record breaking numbers of calls.
Last updated 26th Jun 2026
A chief at the country’s largest ambulance service has warned people to drink responsibly and avoid exercising outside amid a punishing heatwave which has seen record-breaking temperatures for June.
The country sweltered in exceptionally hot and humid weather for a second consecutive day on Thursday, with rare red weather warnings continuing into Friday.
Temperatures could reach 36C in London.
The Met Office said temperatures had reached 36.7C in Merryfield, Somerset, on Thursday afternoon, provisionally making it the UK’s hottest June day on record.
Schools and nurseries have been forced to closed in the capital.
The London Ambulance Service (LAS) responded to its highest number of life-threatening emergencies ever on Wednesday, and its chief operating officer Craig Harman said they expect “demand to grow day on day over the next couple of days”.
As football fans prepare to cheer for England during Saturday’s Fifa World Cup game, Mr Harman has told people to drink responsibly. He advised people to drink “plenty of water” in between alcoholic beverages.
The chief told the Press Association that it is not just the elderly and people with underlying health conditions affected by the heat, adding: “I’m saying to people I need you to drink water even when you’re not thirsty, staying out of the sun during the hottest parts of the day, and particularly not exercising outside and putting your body under additional heat and strain.”
LAS saw a 50% increase in life-threatening emergency calls compared with a typical Wednesday in June, with the number of cardiac arrests up 30%.
Mayor calls for more aircon
Meanwhile, London Mayor Sir Sadiq Khan has said air conditioning should be rolled out to schools, offices and hospitals in the capital as it adapts to more intense and frequent heatwaves, as he launched the city’s first heat plan to keep Londoners safe.
The current heatwave is driven by a “heat-dome” – an area of high pressure that stalls over a region and traps heat – settling over western Europe and bringing extreme conditions across the continent.
Human-driven climate change, mostly caused by burning fossil fuels, is making such extreme heatwaves more frequent and intense.
Capital to continue to bake
The Met Office extended its red warning until 9pm on Friday for London and parts of east and South East England, stretching across Oxfordshire and Bedfordshire, Hampshire and Kent – the first time it has issued red heat warnings over three consecutive days.
More electricity capacity needed
The National Energy System Operator (NESO) issued an electricity margin notice – which calls on companies to make additional capacity available – for Friday evening due to the temperatures.
A NESO spokesperson said: “Our forecasts are showing tight margins on the electricity system for tomorrow evening (Friday).
“An Electricity Margin Notice (EMN) has been issued to the market. This is a routine tool, and means we are asking market participants to make any additional generation capacity they may have available.
“The EMN does not mean electricity supply is at risk.”