Matt Taylor
BBC Weather

Much like you and me picking up bits of our personality from our parents and the friends we’ve met along the way through our lives, weather systems pick up some of their characteristics from where they originated and the environment they have travelled over to get to us.

While we have seen the air heat up rapidly under a large area area of high pressure or "heat dome" sitting over western Europe this past week, one of the most punishing aspects of this heatwave, the humidity, is down to where the the air in it began its story.

Tracking the movement of the atmosphere backwards we can tell that a lot of the air we are breathing now actually originated in the warm and humid mid-Atlantic.

It picked up more moisture as it crossed over the sea and then ended up trapped, circulating around the high pressure system that’s with us now.

It’s that moisture that has increased humidity levels and along with the heat made days and nights so brutal. By contrast, when we had the record-breaking heat in 2022, the air actually originated in West Africa, travelling up via Iberia to us and was therefore much drier.

And the temperature continues to rise - the provisional June record now stands at 36C, which was recorded in Wisley, Surrey.

Ben Rich
Lead Weather Presenter

When a new record temperature is reached, it is almost always described as “provisional”, like today's new June record of 35.7C.

This is because the Met Office - along with national weather services around the world - has a responsibility to make sure weather and climate records are accurate and consistent, meeting internationally-agreed standards.

Once a provisional temperature is set, checks will be carried out to make sure the measuring equipment is properly calibrated and that conditions around the site at the time of the observation didn’t have an impact on the readings.

For instance, a record could be discounted because temporary buildings were erected close to the measuring site or even because the grass or plants close to the weather station were not properly maintained.

In 2022, a temperature of 35.1C that was recorded at Floors Castle in the Scottish Borders – and provisionally thought to be a new record for Scotland – was discounted because the site didn’t meet Met Office standards.

This quality control process can take days or weeks, and a record will remain provisional until those checks are completed.

Image source, EPA/Shutterstock

Climate change has led to more frequent and intense heatwaves, says the Met Office's chief scientist.

Professor Stephen Belcher says human-induced climate change has made events like this "more likely and more intense".

"To see temperatures like this in the UK in June is sobering," he adds.

Met Office projections indicate hot spells will become more frequent in the future, particularly over the south-east of the UK.

Temperatures have soared to 35.7C in Charlwood, Surrey, surpassing the UK's previous June temperature record from 1976 of 35.6C.

BBC Wales News

Transport for Wales (TfW) has cancelled services across Wales due to extreme heat and a shortage of trains.

Routes affected are between Manchester and Cardiff, Coryton and Penarth, Ebbw Vale and Cardiff, Bridgend and Maesteg, Chester and Wrexham, Llandudno Junction and Blaenau Ffestiniog, and Pontypridd and Cardiff Bay.

Most routes will remain cancelled until the end of the day, the operator warns.

Sadaf Maruf
Your Voice news editor

Davide and Vanessa got in touch with BBC Your Voice after the third lift in their 23-storey building broke down this week due to the heat.

The increasing temperatures have taken a toll on the residents of the block in Canary Wharf trying to leave their flats or go home.

Davide says he had to help a woman with a baby climb up to her flat on the 20th floor yesterday, and there are a few elderly people living in the building's 134 flats.

He says residents were told it would be within four hours but they are still waiting and have heard nothing since yesterday,

Vanessa, who rents her flat and has lived in the building for two years, says she had to climb 16 floors with her husky Luna after work using the small airless emergency stairs.

“Its now been 48 hours in this heat. Its just ridiculous, “ she says. “There are always issues with the lifts but never all three out of order.”

The company that manages the building, Sanctuary, has apologised for the issues and says in a statement “our lift contractor is working hard to restore them and we are clear on the urgent need to resolve the problems as soon as possible".

Another temperature update - 35.3C has been recorded in Gosport, Hampshire, and Wisley, Surrey.

We are getting very close to that June record of 35.6C.

Image source, Solentgirl / BBC Weather Watchers

Lola Schroer
BBC News, reporting from Richmond

As temperatures continue to soar, people here in Richmond are finding different ways to stay cool.

Along the riverside, some have been dipping their toes inside, while others have been seeking relief at ice cream vans or retreating to air-conditioned pubs for lunch.

But despite the heat, not everyone is slowing down.

Local fitness instructor Zhivka Slavova taught a yoga class this morning and says turnout was still strong.

She says if people want to stay active during the hot weather it's "important to stay hydrated" and to "prioritise low impact exercise and movement" if you are going to leave the house.

The highest temperatures recorded so far today have been at Bournemouth Airport and Thorney Island in West Sussex, where it was 34.7C as of 14:00.

That tops yesterday, when the maximum temperature in England was 34.6C - and it's going to get hotter still.

Forecasters says the UK’s June temperature record, which stands at 35.6C, could be broken today.

Rowan Bridge
North of England reporter

Image source, Getty Images

The North Yorkshire Moors Railway, which operates steam trains, says it’s switching to diesel locomotives on parts of its route because of the weather.

The volunteer-run railway says it’s taken the decision because of the increased risk of triggering fires by the line in the heatwave.

It says problems could be caused by sparks coming out of the train’s chimneys potentially starting fires.

It’s switched to diesel for the route which runs between Pickering and Grosmont through the North Yorkshire Moors.

It’s still running steam trains in the areas at lower risk between Grosmont and Whitby, but says it’s monitoring the situation.

Yasmin Malik
BBC Newsbeat

Image source, Jake Bird

Telecoms engineer Jake Bird is among those who can't avoid the sun when he's at work.

The 21-year-old from Oxfordshire spends his working day climbing up telephone poles in full PPE and a harness.

He says he plans to keep working as he's self-employed but will have to take strategic cooling breaks.

Jake adds: "Here it’s going to be 36 degrees and that is just insane, especially going up a pole in all that kit and everything. It’s just going to be absolutely dreadful."

Image source, Getty Images

The majority of Eurostar's trains are continuing to operate on both cross-Channel and continental routes, but the operator advises vulnerable passengers to postpone their journey "where possible".

A spokesperson for the high speed rail operator says it has a small number of cancellations due to extreme heat conditions affecting rail infrastructure.

High speed trains between Brussels and the French border will "run at reduced speeds", at the request of Belgium's infrastructure network operator, the spokesperson says.

This will not affect London-Paris trains, and the company adds that Eurostar customers can change their journey for free if they wish to travel outside the heatwave.

Hazel Shearing
Education correspondent

We've now counted 837 schools in England which have fully or partially closed, or which are offering parents the option to pick their children up early.

Most schools are open, but that doesn't mean all their pupils are present. Some trusts have reported a big impact on attendance.

Education Secretary Bridget Phillipson is warning that pupils in England shouldn't be missing school when they can go in because they'll miss out on learning.

"I know hot weather can be a struggle. But my message to families is simple: if your child’s school is open, you should keep sending them into school," she says.

“Every day of absence and lesson missed has a cost – and that cost falls hardest on our most disadvantaged pupils and working class communities.”

She adds that relaxed uniform rules are among the things schools are doing to keep children cool, and any family with concerns about medical needs should talk to their school.

Hundreds of schools are also fully or partially closed in Wales.

Temperatures in England reached 33.9C at 13:00 this afternoon, recorded at Thorney Island in West Sussex.

Cavendish in Suffolk was 33.6C at the same time, while both Wisley in Surrey and Shoreham in West Sussex reached 33.4C. A maximum of 39C is not out of the question for southern England on Wednesday.

It was 30.3C in Cardiff, Wales. In Scotland, the 13:00 temperature was recorded as 24.2C in Charterhall. In Northern Ireland, it reached 23.4C at Castlederg.

Image source, PA Media

Letters and parcels will continue to be delivered as normal through the heatwave, Royal Mail says.

But the company says measures are in place to help manage the severe heat for postal workers.

It says local teams will review their plans and "adjust working arrangements where needed" to avoid over-burdening staff during the hottest parts of the day.

Manish Pandey
Live reporter

Image source, EPA/Shutterstock

Temperatures have continued to rise throughout the day, with highs of 37 or 38C expected to break the record for June later.

The Met Office's red warning for extreme heat is in effect and has been extended to 23:59 BST on Thursday.

The East Midlands, East of England, London & South East England, South West England, Wales and the West Midlands are all included - read more on what an extreme heat warning means for you.

High humidity will make it feel particularly hot when combined with the strong sunshine, says our forecaster.

The heat has caused significant disruption, with over 1,000 schools fully or partially closed in England and Wales.

Transport has also been hit, with rail operators altering their services and National Rail warning passengers not to travel unless absolutely necessary.

Meanwhile, in Europe the heatwave continues, with half of France remaining under a red heat alert.

Peter Gillibrand
BBC Newsbeat

Image source, Supplied

Bricklayer Elijah knows a thing or two about working in the elements.

He spends every working day outside and tells BBC Newsbeat that getting through bad weather, be it cold or heat, is just “part of the job”.

“I tried to keep the complaining to a minimum because about ten months of the year, you're in rain and the cold,” he says.

He admits the heat has been “a lot to deal with”, adding: “We've been starting early, at like 06:30 or 07:00, and trying to get out by midday because by [that time], there's not much you can really do at that point.”

He's laying on water and ice lollies to help keep his employees cool but says “I tell people if they don't want to come in because of the heat don't bother, don't risk it".

Esyllt Carr
Business reporter, BBC News

Image source, Getty Images

Greggs has temporarily closed 11 stores today and tomorrow for the safety of staff and customers.

Staff at one London branch say employees have been moved from one shuttered store to others around capital, telling the BBC: “It's very hot. We have industrial ovens but no proper air conditioning in stores.”

The stores affected are: Aldridge, Wolverhampton, Luton, Gosport, Trowbridge, Barnet, Marlborough, Wantage, Dudley, Northampton and Leicester Square, London.