What is the forecast for the rest of the week?
The Met Office said that the mercury is expected to push 30C (86F) across southern and western England and 25C (77F) in Belfast, but scattered thunderstorms are also forecast to return.
The previous high for the year was 31.6C (88.88F), which was also recorded at Heathrow on Sunday.
Public Health England has extended its heat-health warning, which warns people to take measures to stay cool and look out for vulnerable people, until Friday.
Heatwaves are becoming more frequent and extreme because of climate change driven by human activity, with scientific analysis finding events such as 2019’s record heat in the UK and Europe and the devastating heatwave in Canada and the US in recent weeks were made much more likely and more severe by global warming.
The world has already warmed by about 1.2C since pre-industrial times and temperatures will continue to rise, causing greater climate impacts, without urgent and significant global action to cut greenhouse gas emissions.
Scattered thunderstorms are forecast to return across the country’s east but are not expected to be as serious as the downpours which saturated south-eastern and central England on Tuesday.
Sun melts roads
Local authorities have reported having to carry out urgent repairs to roads which have melted in the heat.
Gloucestershire Council Council said that “emergency work” has been carried out on the A38 in Tewkesbury to repair damage caused by the current heatwave.
Somerset County Council said on Twitter that a number of roads had been affected by the heat and that a sunny day with temperatures of around 20C can be enough to heat the roads to 50C.
It added: “The blistering heat has caused some roads to melt (yes, melt). We are doing all we can to protect the roads.
“We will continue to monitor the situation over the next few days.
“A sunny day in the 20Cs can be enough to generate 50C on the ground as the dark asphalt road surface absorbs a lot of heat and this builds up during the day with the hottest period between noon and 5pm.”