The Met Office has extended its amber warning for extreme heat to cover Tuesday next week as temperatures in the capital are expected to be hotter than 35C.
Now the warning for extreme temperatures covering much of England and Wales, including London, is now in place from Sunday until the end of Tuesday.
The peak of the heatwave is expected to hit Monday or Tuesday - with some models suggesting the UK could see its highest temperatures ever recorded.
“Population-wide adverse health effects are likely to be experienced, not limited to those most vulnerable to extreme heat, leading to potential serious illness or danger to life,” the warning stated.
It added: “Delays on roads and road closures are possible, along with delays and cancellations to rail and air travel, with potential for significant welfare issues for those who experience even moderate delays.”
Temperatures are expected to peak in excess of 35C in London into the start of next week.
Met Office Deputy Chief Meteorologist Rebekah Sherwin said: “Today (12 July), temperatures are likely to peak at 31C in the southeast, with warm weather likely to continue throughout this week and it looks likely to ramp up late this week and into early next week.
“From Sunday and into Monday, temperatures are likely to be in excess of 35C in the southeast, although the details still remain uncertain.
“Elsewhere, temperatures could be fairly widely above 32C in England and Wales, and in the mid-to-high 20s Celsius further north.”
Thames Water, which supplies most of Greater London, issued a warning to customers to limit water consumption around the home during the hot spell.
Andrew Tucker, Water Demand Reduction Manager at Thames Water, said: “While we’re not currently expecting to introduce restrictions on water use this summer, it’s important that households remain responsible with their usage and help us to limit the pressure on our resources.”
