Image source, PA Media

Our analysis suggests that across the BBC South region more than 140 schools are closed or partially closed today because of the high temperatures.

It means more than 60,000 pupils are likely to have been affected.

The number is set to rise to more than 200 schools on Wednesday, with more than 100,000 pupils affected in some way.

While there is no legal maximum temperature for classrooms, schools are expected to safeguard students from risks to their health.

Image source, University of Oxford

OK, we mean a different kind of degree, as at the Encaenia ceremony, external at the University of Oxford tomorrow nine honorary degrees will be handed out.

They will be awarded to Dame Jacinda Ardern, Prof Daron Acemoğlu, Carlos Acosta, Adjoa Andoh, Prof Henry Louis Gates Jr, Prof Katalin Karikó, Billie Jean King, Prof Shuji Nakamura and Dame Emma Walmsley.

But as the Met Office has issued a red extreme heat warning for Oxford the university says the "usual expectations regarding formal attire have been relaxed".

Image source, University of Oxford

"Guests are welcome to dress in a way that is comfortable and appropriate for the conditions," a university statement says.

"Jackets, gowns and other additional layers are not expected, except for those participating in formal processions, where wearing them remains optional."

Bridport Youth Football Club, external has cancelled all training for the next three days due to the weather warning.

The club said the decision had been made by the club management to protect players and staff.

It said it hoped training would resume on Friday evening.

Image source, Reuters

Tankers have been brought in to pump water to keep taps flowing in the Witney area after a pipe burst.

Thames Water said the burst pipe at Poffley End, external meant those in the OX29 postcode area had no water or low pressure.

The water firm said temporary traffic lights had been set up while the pipe is fixed and supplies restored.

Thames Water said: "We know how disruptive it is to be without water and we'd like to thank you for your continued patience while we carry out these repairs."

The National Education Union, which represents school teachers, staff and teaching assistants, has warned the high temperatures could cause a "serious and imminent threat of danger" in schools.

Joint branch and district secretary Bruno Duckworth-Russell, writing to headteachers, cited Met office warnings about the heat which he said would "pose a serious threat to the safety of not only our members but the students under our care".

It said come schools were "not well-ventilated enough" and could reach "40 degrees or more" as temperatures rise.

"We are aware some headteachers have carried out their own risk assessments and implemented measures such as changes to uniform and school activities, however we do not think these measures are sufficient to safeguard school communities or our members.

"We have also heard the voice of parents who are worried about their child’s safety and are aware that many parents – many of whom are also our members too - plan to keep their child at home on these days," he added.

Image source, LSD Promotions

The popular Gloucester Green Market in the centre of Oxford will not operate on Wednesday and Thursday this week.

LSD Promotions, which operates the market, said the decision was "due to extreme weather warnings for heat".

The busy outdoor market off George Street usually runs four times a week.

Image source, University Hospital Southampton NHS Foundation Trust

University Hospital Southampton NHS Foundation Trust has issued a warning that its Emergency Department (ED) is "extremely busy right now, and temperatures are rising".

"We are trying to limit the number of people waiting in our ED," it says.

"Please only attend if your condition is an emergency. If you do need to come, please attend alone where possible or kindly keep numbers to a minimum.

"Thank you for your understanding and support."

Sam Fraser
Weather presenter, BBC South Today

If you’re wondering why this week’s heatwave feels unusual, that’s because it is!

A powerful high-pressure system has planted itself firmly over southern England, and it’s reluctant to move.

In simple terms, that high pressure acts like a giant atmospheric lid - literally a heat dome - it suppresses cloud formation, pushes warm air downward, and shuts out any cooling breeze.

When that high sits stubbornly in place for days at a time, as it has this week, there's simply nothing to interrupt the heat building beneath it.

The real story lies in where this air has come from. A strong southerly flow ahead of the high is drawing warmth all the way from the Iberian Peninsula and North Africa.

By the time that air mass reaches us here in the south of the UK, it has already spent days travelling over sun-baked continental land, arriving dry and extremely warm.

Crucially, as this intense heat bakes the UK landscape, it is trapping moisture near the ground creating humidity that’s contributing to the unusually high heat index.

The high-pressure system is forecast to nudge eastward by the weekend, allowing a fresher Atlantic flow to filter back in from the west.

Temperatures should ease noticeably by Saturday, though that transition may trigger some heavy, thundery showers before cooler air fully establishes itself.

For the time being, stay out of the sun as far as you can, stay hydrated and keep your curtains closed!

Dave and Candy Scales in Banbury remember the summer of 1976 not just for the heat - it was the year they got married.

The famous 1976 heatwave saw 15 consecutive days of temperatures exceeding 32C.

Keeping cool in the shade in People’s Park, Candy recalled: “It actually rained the morning, and we had the reception in the afternoon.

“It was really, really hot.”

Dave added their honeymoon in Ilfracombe was only hot for one day, and that it rained for the rest of it.

"Apart from that, the summer of 1976 was lovely and warm… people just got on with it,” he said.

The Met Office and UK Health Security Agency have issued rare red warnings for Wednesday and Thursday with significant health and infrastructure impacts expected.

BBC South's environment correspondent Jon Cuthill explains that climate change means we'll see more of these kind of weather conditions.

Image source, PA Media

Rail passengers planning to travel on Wednesday or Thursday are being advised to do so only if absolutely necessary.

National Rail, external has said those with a ticket for travel within the Met Office red extreme heat weather warning, external area on Tuesday, Wednesday or Thursday can use it to travel on Friday instead, or can claim a full refund.

• GWR, external said it would be running fewer trains with slightly longer journey times expected.
• SWR, external said an amended timetable would be running on Tuesday, Wednesday and Thursday.
• Southern, external said its services would be reduced in some parts of the network and passengers should expect disruption.
• Cross Country, external urged travellers to check their entire journey before travelling and be prepared for short notice changes and cancellations.
• Island Line, external said passengers should only travel if absolutely necessary on Wednesday and Thursday. Services may also be subject to short-notice changes and cancellations.

Image source, South Central Ambulance Service NHS Foundation Trust (SCAS)

South Central Ambulance Service NHS Foundation Trust, external (SCAS) is urging people to keep 999 free for life-threatening emergencies during the heatwave.

The ambulance service covering Berkshire, Buckinghamshire, Hampshire and Oxfordshire said it was preparing for higher demand but warned that patients with less serious issues may face longer waits as crews prioritise life-threatening emergencies.

It also urged people not to call the emergency telephone number again just to ask when their ambulance would arrive after seeing a spike in 999 follow-up calls during the recent warm spell in May.

The trust is also encouraging patients who are well enough to make alternative travel arrangements to hospital, where appropriate.

Tuesday will see exceptionally hot and humid conditions under sunny skies and a gentle south-easterly breeze.

A few isolated patches of cloud may occasionally drift by through the day.

Image source, Oxfordshire County Council

On Wednesday and Thursday waste and recycling centres in Oxfordshire will open at 08:00 and close early at 13:00 BST due to the high temperatures.

Oxfordshire Recycles, external said: "Thanks to the booking system, we have been able to notify those who had booked a slot, saving any wasted journeys as a result of this early closure.

"Those who had bookings have been invited to rebook their visit for an alternative time."

Image source, Reuters

Schools in Hampshire, Berkshire and Oxfordshire and Dorset have announced closures and reduced hours due to the heat.

Schools usually contact parents in their own ways, often through apps or messaging services.

Hampshire County Council, external and West Berkshire Council, external post a list of reported emergency closures.

A list of schools that have had to close suddenly is also posted on the Oxfordshire County Council website, external. The council said it relies on schools to tell it when they are closed.

Image source, BBC Weather Watcher Slim

The highest overnight temperature was 20.4C in Gosport.

The Met Office said eight other places including Hurn in Dorset and the Isle of Wight recorded a tropical night - where temperatures did not fall below 20C.

Image source, Reuters

Homes and businesses in parts of Witney, Oxfordshire are facing disruption to their water supplies.

A burst pipe at Poffley End means those in the OX29 postcode area have no water or low pressure.

Apologising Thames Water , externalsaid: "We're currently working to isolate this burst pipe and will be able to begin repairs shortly after."

The water firm said it hoped to have an update by 11:00 BST.

The UK is likely to experience its hottest June day on record on Tuesday with temperatures forecast to rise above 35C (95F).

The highest June temperature on record of 35.6C was set on 29 June 1957 at Camden Square in London, then equalled on 28 June 1976 at Mayflower Park in Southampton.

You can find out more about the 1976 heatwave in the South here.

Image source, Getty Images

A Southampton MP has urged parents to talk to their children and teenagers about safety in the water as temperatures soar.

The Labour MP for Southampton Itchen, Darren Paffey, led a Parliamentary debate on water safety education earlier this month following recent drownings, including several in the south.

He said such incidents were "a stark reminder that we cannot afford to take risks or assume that everyone knows what to do in an emergency”.

He added: “These may feel like simple messages, but knowing them could make the difference in an emergency. A short conversation around the dinner table today may well save a life tomorrow.

“Please enjoy the water and everything our waterfront city has to offer this summer, but please do so safely.”