In 2020 the Met Office published a hypothetical forecast , externalfor a week in July in 2050 - to show the impacts of climate change on our lives in coming decades.

But atmospheric scientist Dr Simon Lee tweeted that forecast now looks very similar to the predictions for today and tomorrow. In both forecasts, London is at 40C and Hull at 38C.

The Met Office told BBC News we are reaching temperatures now that were thought highly improbable a decade ago.

The heat we are experiencing this week is more in line with the extremes for 2050, they added.

Projections for 2050 also show the potential for temperatures to reach the low and mid-40s during extreme weather events.

Let's take a look at where things stand at midday.

According to the Met Office, Charlwood in Surrey recorded the highest temperature of 34.8C

A number of other areas in London, Surrey and Suffolk have now hit 34C.

This makes it the UK's hottest day of the year so far.

Sunday was previously the warmest day of the year, with temperatures in Hawarden in Wales reaching 33C.

Is the heat worse in urban areas?published at 12:35 British Summer Time 18 July 2022

12:35 BST 18 July 2022

Pallab Ghosh
Science correspondent, BBC News

Image source, EPA

We've been taking readers' questions about the heatwave. The first one comes from Derek, who asks if the temperatures we are experiencing will be even higher in built-up towns and cities where the reflection of the sun is magnified off the windows of high rise buildings.

Large urban areas tend to be warmer because there is relatively little bare earth and vegetation and a high concentration of man-made materials which absorb heat, rather than reflect it.

This phenomenon is known as an urban heat island, external and while heat generated by transport can contribute, the reflection of the sun off windows does not.

As London has the largest urban sprawl it tends to have record high temperatures.

Vanessa Clarke
Education reporter, BBC News

At Hadfield nursery school in Glossop in Derbyshire this morning, preschool children arrived in sunhats, shorts and summer dresses.

The headteacher Ken Weed says all the children have sun cream on but they won’t be going out in the direct sunlight. They have 10 fans dotted around the building and have bought hundreds of ice pops for the children.

They are also planning to take the students outside to their shaded wooded garden for story time and have lots of water activities planned for under the shelter “so water trays, water play and lots of splashing going on.”

The teachers have “gallons and gallons of water ready” and will be keeping a very close eye on every child for any signs of exhaustion.

The Department for Education in England has issued advice, external for school leaders saying schools should avoid "vigorous physical activity" and to make sure children have access to plenty of water. Similar advice, external has been released in Wales.

Matt Taylor
BBC Weather

France may have experienced its warmest July night on record last night with temperatures not dropping below 27.5C in Nice.

The warmest July night in the UK was back in 1948 at St James’s Park, London where the temperature remained above 23.3C.

Some UK locations could be close to that tonight.

As temperatures across the UK continue to climb, here are some pictures from around the country:

Image source, Reuters

Image source, PA Media

Image source, PA Media

Image source, PA Media

As of 11am, temperatures have reached or surpassed 32C in three locations in England:

• 32.3C at Writtle, Essex
• 32.1C at St James' Park and Kew Gardens, London
• 32 Wisley, Surrey

And this is an overview of maximum recorded temperatures so far across the UK today:

• Wales: 30.8C at Gogerddan
• Scotland: 25.9C at Edinburgh (Gogarbank)
• Northern Ireland: 24.3C at Stormont Castle

Sarah Keith-Lucas
BBC Weather

This is the first time forecasters have ever put temperatures of 40C plus on the UK map.

Although it is shocking, it doesn’t come as a huge surprise when we have been talking about climate change driving temperatures up for the past 30 years.

Image source, PA Media

You may be asking why trains are running a lot slower than normal - or not at all.

That's because metal rails can warm up to 20C hotter than the air temperature when they're exposed to direct sunshine.

The rails are made from steel, which absorbs heat easily, and expand when they heat up and risk bending, flexing and even buckling.

When a railway network's monitoring systems warn that a section of track is likely to become overheated and expand, speed restrictions are put in place to reduce the chances of this happening.

Rail workers also use a method called 'stressing' to prevent railway lines from bending in the heat - painting rail tracks white helps reduce the heat absorbed by up to 10C.

Network Rail have more information on hot weather and the railway here, external.

Officers searching for a missing 13-year-old who got into trouble in a river near Ovingham, Northumberland, have found a body, Northumbria Police have said.

The police have said the teenager's body was found following extensive searches by the force's marine unit.

In an unrelated incident, a 51-year-old man also died on Sunday after a kayak capsized on the River Spey, in Moray.

Police said the alarm was raised at about 4.45pm. Emergency services recovered the man from the water but he was pronounced dead at the scene.

Image source, PA Media

With London set to be hotter than Kingston, Jamaica, today and tomorrow, many people will no doubt flock to London’s green spaces - despite warnings to avoid the heat.

But, the director of London’s Royal Parks - which include Richmond, Greenwich, St James’, Bushy and Regent’s Parks - have urged visitors to take extra care.

“Over the next few days, the Royal Parks will be on fire watch,” he says.

“We are asking that visitors help us reduce this risk by not bringing [disposable] BBQs to the parks, not putting out cigarettes ends on the ground, and not leaving glass bottles or glasses out in the sun, so as to avoid magnifying the sun’s rays and starting a fire."

Wildfires are already happening elsewhere in the UK. Near Ipswich in Suffolk, eight fire crews tackled a wildfire that took hold in a field on Sunday.

And firefighters in Shropshire have tackled 10 wildfires since Friday evening.

Nick Miller
BBC Weather

It’s notable how quickly temperatures are shooting up this morning.

Wisley in Surrey was just 12C at 6am this morning and by 10am it was the hottest place in the UK at 30.2C

Image source, Getty Images

Forecasters predict we could see highs of up to 40C today in and around the London area, 37C in Birmingham, 35C in Norwich and Cardiff, and 31C in Newcastle and Cornwall.

In Scotland, temperatures in Edinburgh are expected to get up to 29C.

In Northern Ireland highs of 27C are forecast near Belfast.

Find out how hot is it where you are here.

Victoria Gill
Science correspondent, BBC News

Image source, PA Media

This particularly dangerous hot spell is being driven by southerly winds bringing hot air from North Africa and the Sahara. That is not an unusual weather pattern, but the sheer intensity of this heatwave is being fuelled by global warming.

By turning up the world’s thermostat, climate change is also set to increase the frequency of events like this.

Climate attribution scientist at the Met Office, Dr Nikos Christidis, said that the likelihood of extremely hot days in the UK has been increasing and will continue to do so during the course of the century, with the most extreme temperatures expected to be observed in the south-east of England.

Dr Hannah Cloke from the University of Reading said the red warning for extreme heat should be “a wake-up call about the climate emergency”.

“Even as a climate scientist who studies this stuff, this is scary,” she said. “This feels real.”

We've heard lots about the dangers of extreme heat for some elderly people and those who are considered vulnerable - but what about animals in the agricultural industry?

In Wales, it isn't just humans using sun cream - but pigs as well. Some farmers are covering their animals in sunscreen to protect them from getting sunburnt.

"Pigs don't let out the heat as well as other animals so it is difficult to keep them cool," award-winning pig farmer Ela Mair told the BBC.

Meanwhile, at the Royal Welsh Show, one of Europe's biggest agricultural events which is happening over the next four days, organisers have spent around £50,000 on extra fans and ventilation in livestock sheds to keep the approximate 8,000 animals as cool as possible.

In the city of Chester, in north-west England, the zoo has said it'll be closed on Monday and Tuesday to keep its animals, visitors and staff safe.

It's a fast-moving situation in terms of latest travel news, but many train companies have already announced disruption today:

• Greater Anglia, Cross Country, GWR, Northern, TransPennine Express, Southeastern and many other operators are running slower services
• East Midlands Railway, Hull Trains, LNR, Lumo, East Coast Main Line, West Midlands Railways, Chiltern Railways and Transport for Wales all said they are operating a reduced service
• Avanti West Coast has suspended ticket sales on Monday and Tuesday
• On ScotRail, a number of speed restrictions will be imposed across the railway network from 13:00 BST to 20:00 to help reduce any potential damage to the railway line and/or overhead wires
• In London, parts of the Overground, the Metropolitan and the Hammersmith and City lines are suspended due to heat-related reasons. Several lines are also experiencing severe delays
• Network Rail says people should travel only "if absolutely necessary" , externaland some cancellations have already been announced. Speed restrictions are also in place across the network.

Image source, PA Media

"We may well see the hottest day in UK history," according to Prof Penny Endersby, chief executive of the Met Office. She also warns more high temperatures are expected tomorrow, as the hot air pushes further north.

"Tomorrow there’s a higher chance of 40C and above, possible numbers 41 are the cards some 43 in some models, but we’re hoping it won’t be as hot as that," she tells the BBC.

But Endersby fears some people aren't taking the warnings seriously, “they think we shouldn’t be telling them to worry about heat the way they should when we tell them to worry about storm or wind”.

"These temperatures are unprecedented and we’re not used to dealing with them - heat causes many hundreds or thousands excess deaths, so people need to follow the advice of keeping the shade, keeping cool and hydrated."

She says significant studies carried out on the probability of the UK seeing temperatures of 40C, shows these temperatures are unattainable here without climate change. She adds by 2100, we could see these temperatures every “one in 15 or one in three years depending on emissions pathways we take between now and then”.

Celestina Olulode
BBC News

At the height of rush hour the London Underground was a lot cooler and quieter than normal.

Some carriages were almost empty apart from a few passengers. In one carriage leaving central London’s Oxford Circus we counted 13 passengers, so lots of free seats available for commuters.

From the looks of things it appears that passengers are following Transport for London’s advice and avoiding travel.

But although there weren’t the usual hoards of sweaty commuters, temperatures were still high. At 8:15am we measured a temperature of 33C (91.4F).

Meanwhile, over in King's Cross station, tannoy announcements alerted passengers of Met Office warnings and cancellations of some trains to Leeds and York due to weather conditions.

Temperatures are starting to rise rapidly now, says BBC Weather's Sarah Keith-Lucas.

Highs of up to 40C are forecast around the London region. It's not as hot the further north-west you go, but there are high 20s across the north of Scotland.

And tomorrow could be even hotter - with up to 42C possible. But there will be some showers and fresher air moving into the north-west of the UK.

Image source, .

As it begins to get warmer, here are some tips to help you today.

Draw the curtains or blinds to keep the sun out and close the windows on the sunny side of your home - that should help keep the hot air out.

Open all the windows before you go to bed to get a through breeze.

Using even a small fan can be sensible in hot weather as it encourages the evaporation of sweat and makes it easier for your body to regulate your internal temperature.

If you don't have a fan, try filling a hot water bottle with ice cold liquid instead.

Alternatively, cooling your feet lowers the overall temperature of your skin and body, so try chilling your socks in the fridge before you put them on.

And of course, keep hydrated and drink plenty of water.