There is now a 90 per cent chance the UK will set a record temperature this week and a 60 per cent chance it will reach 40C, according to the Met Office’s Becky Mitchell. London and other parts of south-east England are under a red alert for extreme heat on Monday and Tuesday, with highs forecast to reach 41C in some places. The previous UK record temperature of 38.7C was set in Cambridge in 2019. Areas of southern Scotland, including Dundee and Perth, are now on yellow alert. While such high temperatures are common in some other parts of the world, Britain’s typically mild climate means that infrastructure such as railway lines and buildings are often not designed to cope with extreme heat. Both Network Rail and Transport for London have warned of disruption due to the risk of rails bending in the heat and have asked passengers to only travel if necessary. There will be no services on the East Coast Main Line between London King’s Cross and York and Leeds on Tuesday afternoon, with only one skeleton service in the morning. “The predicted temperatures are much higher than what our infrastructure is designed for,” Network Rail said. Such hot weather also poses serious health risks, including heat exhaustion and heat stroke, and is associated with increased mortality rates. A woman holds a fan as she travels on the London Underground: rail networks have warned of disruption due to the risk of rails bending in the heat © Maja Smiejkowska/Reuters Cabinet minister Keith Malthouse is to chair a meeting of the government’s Cobra emergency committee on Monday as he ramps up preparations for what has been declared a “national emergency”. Boris Johnson, the outgoing prime minister, was criticized on Saturday after he failed to attend a meeting of ministers and Cobra officials to discuss the coming heatwave. Johnson stayed instead at his country house in Checkers, ahead of a thank-you party for supporters on Sunday. Senior government officials held a meeting on Sunday to discuss the potential impact of the heat on the transport system and the NHS. Network Rail, the rail infrastructure operator, will set speed restrictions in England and Wales between 12 p.m. and 8 p.m. on Monday and Tuesday. TfL will also implement speed restrictions on some parts of its network, resulting in reduced services and delays. Dominic Raab, deputy prime minister, said on Sunday it was up to employers whether their staff worked from home.

But Malthouse suggested this could be appropriate because of the disruption to services, saying: “If [staff] you don’t need to travel, this can be a time to work from home.” The GMB union called for a maximum indoor workplace temperature of 25°C in line with World Health Organization guidelines. Health Minister Steve Barclay met with ambulance chiefs on Saturday and said extra support would be provided for health services on Monday and Tuesday. NHS providers, representing leaders across the NHS, warned there could be disruption to some planned care, as well as added pressure on urgent care, with staffing levels already affected by Covid-related absences. “We are hearing that some surgeries are having to stop because they are getting too hot,” said Miriam Deakin, director of policy and strategy at NHS Providers. “The conditions are also making it difficult to keep essential services running.” The Ministry of Education is not advising schools to close. But some school principals said they were making local decisions to close early Monday. The Harris Federation, a group of 51 academies, said in buildings where heat was a known issue, schools would close at 1pm after lunch was served, but would remain open for children who wanted to stay. Steve Chalke, the founder of the Oasis academy chain, said schools are adapting to their particular circumstances but will all remain open as children’s homes will often be warmer than school.