A new record for the hottest day ever seen, of 40.3C, was recorded in Coningsby, in Lincolnshire, on Tuesday afternoon – beating the previous record of 38.7C in Cambridge three years ago, by 1.6C.
Amid the sweltering heat, major incidents were announced by fire brigades in London, Leicestershire and South Yorkshire as dozens of fires broke out amid the sweltering heat – with flames ripping through houses, schools and churches.
It comes as the temperature is set to drop by up to 10C in some areas on Wednesday, with heavy showers and thunderstorms to lash parts of the country, potentially causing localised flooding.
The Met Office said 34 observation sites across England provisionally broke the previous all-time record, ranging from Bramham, in West Yorkshire, to Charlwood, in Surrey, while a further five had equalled it on Tuesday.
A total of six sites, mostly in Greater London, saw temperatures reach or exceed 40C.
Scotland experienced its hottest day on record, with the temperature reaching 34.8C in Charterhall in the Scottish Borders, Met Office provisional figures showed.
However, two “large-scale” incidents took place in Upminster and the village of Wennington, east London, where black smoke billowed into the air, while flames destroyed buildings and ravaged nearby fields.
Several other significant incidents also occurred in the capital, with people urged not to have barbecues or bonfires due to the “unprecedented” challenges crews face.
Jonathan Smith, assistant commissioner at London Fire Brigade, earlier told the PA news agency crews would continue to tackle the flames into the evening.
He also said: “It would be premature to say we are out the other end of this incident”.
New smaller fires, related to the hot weather, were continuing to crop up in different corners of the city by 11pm on Tuesday.
Elsewhere, a serious blaze occurred in Barnsley when a row of houses in the Moorland Avenue area was consumed by flames, with crews continuing to battle fires elsewhere in the area.
Doncaster Council said a major blaze in Clayton also spread to three residential properties and there were reports of houses on fire in the Kiverton Park and Maltby areas of Rotherham.
Leicestershire Fire and Rescue tweeted: “We have declared a major incident due to high demand across Leicester, Leicestershire and Rutland.
“We will not be attending Automatic Fire alarms. Please only call us if it’s an emergency.”
It stood down its major incident warning later in the day.
Nine people have died since Saturday in swimming accidents and there has been widespread disruption to train services.
Simon Clarke, the Chief Secretary to the Treasury, told Sky News that the fires were a “warning sign” about the impact of climate change.
“This is a reminder today I think of the importance of tackling climate change.
“This is a remarkable, unprecedented event and something which obviously, because people have been saying, we are not used to seeing in this country.
“What we’ve seen in recent days is not normal and it is a warning sign.”