Britons are being warned of widespread disruption as temperatures look set to reach a dangerously high peak in the coming days.
Forecasters believe there is a 30% chance the mercury could surpass the current UK record of 38.7C, set in Cambridge in 2019, as temperatures continue to climb over the weekend and into next week.
An “amber” extreme heat warning covering much of England and Wales on Sunday and Monday says there could be a danger to life or potential serious illness, with adverse health effects not just limited to the most vulnerable.
There could also be road closures, and delays and cancellations to rail and air travel, while ambulance services in England are on the highest level of alert as difficulties with the hot weather combine with Covid absences among staff and ongoing delays handing patients over to A&E.
Wednesday, Thursday, and Friday are likely to bring some rain in the north of the UK and highs of 27C or 28C – slightly cooler than Tuesday which saw 31C in parts of south-east England.
But temperatures are expected to soar again into the mid 30s through the weekend before peaking on Monday, with south-eastern areas of the UK seeing them climb in excess of 35C, and locally into the high 30s.
Forecaster Matthew Box said: “As we get into Sunday it looks like we could see temperatures rise into the high 20s and into the low 30s as well but potentially a few spots getting 34C or 35C by Sunday and probably the same again on Monday.
“We could see by Monday temperatures getting towards the mid or high 30s and there’s about a 30% chance we could see the UK record broken, most likely on Monday at the moment.”
High temperatures may also last into Tuesday.
“It’s looking like things are going to become hot or very hot as we go through the weekend and into next week,” Mr Box added.
He explained the heatwave is a result of hot air flowing to the UK from the continent.
He said: “What happens as we get into the weekend, the high pressure becomes centred to the east of the UK and that allow a southerly flow of air to drag up, the very warm air that’s over France at the moment, and drag it northwards to the UK over the weekend, perhaps more so on Sunday and into Monday.”
Heatwaves have been made hotter, longer and more frequent by climate change, and experts have warned of the need to adapt homes and cities in the UK for a future of more intense summer heat.
Network Rail is preparing to introduce speed restrictions to reduce the likelihood of tracks buckling as the heatwave continues, which will cause delays to passenger journeys and disrupt freight services.
London Ambulance Service urged the public to support it as the heat continues by only calling 999 in the event of a life-threatening emergency, keeping hydrated and staying out of the sun during the hottest periods of the day.
The Royal Life Saving Society UK warned people about the dangers of trying to cool off in lakes, quarries, rivers and other waterways in the extremely hot weather.