Health chiefs are urging Londoners to take extra care as another spell of extreme heat grips the capital.
An amber heat health alert remains in place until Sunday, with forecasters warning the prolonged hot weather is placing significant pressure on health and social care services.
New NHS figures published today show there were 428,463 A&E attendances and 130,929 ambulance incidents across London in June, as health leaders warn services are under exceptional strain.
Temperatures reached 35C in Northolt on Thursday afternoon, according to the Met Office, while Surrey recorded a UK high of 35.5C.
It also marked a record-breaking eighth day this year that UK temperatures have reached at least 34C, surpassing the previous record of seven days set in 1976 and 2020.
BBC Weather’s Tomasz Schafernaker told Radio 4’s Today programme people will be “melting” as temperatures soar, noting that London would see its “absolute peak” temperature on Thursday. Temperatures are set to drop to the high 20s as we enter the weekend.
With England’s World Cup quarter-final against Norway also taking place this weekend, health chiefs are urging Londoners to use NHS services wisely, to stay safe in the heat and check in on vulnerable friends and family when they can.
Dr Chris Streather, Regional Medical Director for the NHS in London, said: "Across May and June we saw a significant surge in demand, with over 16,000 more people attending A&E each month and more than 7,500 additional ambulance incidents compared to April — and our teams have risen to meet every one of them.
"Despite these exceptional pressures, NHS staff across London continue to work tirelessly to ensure that everyone who needs care receives it. I want to thank each and every one of them for their dedication during what has been an incredibly challenging period.
"Hot weather places real strain on both physical and mental health, and with temperatures reaching the thirties, it is more important than ever that people act early. We are here for you — but we urge Londoners to use services wisely and not to wait until they are in crisis before reaching out, especially when it comes to mental health.
"If you need support, please call NHS 111 and select option 2 for mental health. It's the quickest way to get the right care, and it helps us protect emergency services for those who need them most."
It comes as the country swelters in the third heatwave of the year, with conditions leading to hosepipe bans and early harvests as well as wider impacts on wildlife and transport.
Scientists say these record-breaking weather events are becoming more intense and more frequent because of climate change, largely driven by the burning of fossil fuels.
Merton Council confirmed that a number of fish have died in Wimbledon Park Lake due to prolonged periods of extreme heat.
Investigations by the Environment Agency and Thames Water indicate that the “likely cause” of the deaths is the exceptionally hot weather, as the heatwave has significantly depleted oxygen levels in the lake.
Council officers are working closely with partners to minimise any further impact.
Meanwhile, widespread delays and cancellations are affecting London’s rail network.
With temperatures reaching 34C to 35C across London and southern England, rail infrastructure is under significant stress, with steel tracks reaching temperatures above 50C.
The extreme heat can cause rails to expand and buckle, overhead electrical wires to sag, and critical equipment to malfunction.
To protect passenger safety, Network Rail and TfL have introduced precautionary speed restrictions, requiring trains to operate at reduced speeds.
UK officials recently warned that the risk of drought conditions in areas of the country this year is becoming increasingly likely, with officials keeping a close watch on East Anglia, Devon and Cornwall.
And, Britain’s electricity grid operator issued another plea to the industry for more power generation, forecasting a tight period for electricity margins for Thursday over “extreme temperatures” in Europe.
It is the third so-called electricity margin notice issued by Neso this year, which is more typically sent during cold spells in the winter when more people are heating their homes.
