The UK has recorded its highest temperature of the year so far, but it is expected to rise further as the week progresses.
A sweltering 28.2C was recorded in Kew Gardens, south-west London, on Wednesday, with forecasters expecting an even higher 29C in the capital on Thursday.
The heatwave in parts of Britain is set to reach a “crescendo” on Friday as temperatures are expected to soar to 34C in south-east England.
Temperatures between 27 and 30 °C are expected in most of England and Wales.
The warm weather stream is coming from Spain and Portugal, where daytime temperatures have exceeded 40°C in southern Spain.
The highest temperature recorded in Britain for June in the UK was 35.6 °C at Southampton Mayflower Park in June 1976, the year of a notable summer heat wave.
Before Wednesday, the hottest day this year so far was the 27.5C set in mid-May at Heathrow.
There will be spotty showers in parts of Scotland and Northern Ireland on Thursday, becoming heavier in western Scotland overnight.
The highest temperature Scotland can expect on Thursday will be 22C, while Northern Ireland will struggle to get above 19C.
On Thursday Wales will potentially see highs of 24C.
Met Office spokesman Grahame Madge said: “We’ve got a lot of pressure right now so there’s a certain amount of homegrown natural heat building up because obviously we’ve got clear skies and pretty dry ground conditions in the south. from England.
“We also have warmer air coming in from further south in Europe, where there has been a big heat incident, particularly in Iberia, so it’s leading to the sort of crescendo that we’re going to see on Friday.
“Because of the direction of the flow, with the weather pattern that we have established at our latitude, that is encouraging this flow of warm air to move further north.
“We have the heat increasing day by day. The next two days will be hotter than the day before. We believe at this time, although there is some uncertainty, that weather temperatures will peak on Friday and then by and large we will have a cooler day on Saturday.
“The heat can potentially stay into Saturday, but over most of the UK, because we have a cold front coming down from further north, we will see temperatures drop back down, but they are likely to stay in the south. from England”.
Dr Mark McCarthy, head of the Met Office’s National Climate Information Centre, said: “Climate change has increased the average temperature of UK summers and is also increasing the likelihood of experiencing more extreme temperatures during summer periods. of heat and heat waves.
“Reaching 34C during June is a rare event, but not without precedent, in UK historical climate records. But if it happened this week, it would be remarkable that it happened on three days in the last six Junes.”
The first aid and health response charity St John Ambulance has issued some tips for coping with the hot weather.
Its medical director, Dr Lynn Thomas, said: “If you’re out and about in the sun, it’s important to make sure you take care of yourself by staying hydrated, staying out of the sun at peak times and using sunscreen with a minimum of SPF30.
“I would also encourage anyone with elderly relatives and neighbors to check with them, as any rise in temperature can be dangerous.”
RAC spokesman Rod Dennis said: “With the temperature rising very rapidly this week, we expect a short, sharp increase in breakdowns, especially in the central and southern parts of the UK.
“It’s important that drivers stay on track, so we recommend that you check your car’s oil and coolant levels as soon as possible, especially if you have a long trip planned in the hottest part of the day.
“Drivers also need to stay hydrated, which has been shown to have a positive effect on their concentration levels.
“Passengers also need to stay as cool and comfortable as possible, so bring plenty of water and plan enough breaks to prevent an already hot car from getting even hotter.”