The UK could experience the hottest day of the year so far on Friday.
The Met Office has warned people not to be “caught out” by the potentially record-breaking temperatures.
The mercury is set to rise to 37C in London and the south east on Friday and could surpass the 37.8C recorded at Heathrow on 31 July – the hottest day of the year so far and the UK’s third warmest ever.
It is the second day of a heatwave which is expected to last until at least Sunday.
Follow the latest updates
Good morning and welcome to the latest updates on what forecasters are saying could be the hottest day of the year.
Forecasters predict hottest day of year
Forecasters have said Friday could be the hottest day of the year.
The mercury is set to rise to 37C in London and the South East on Friday, the second day of a heatwave expected to last until at least Sunday.
It could even surpass the 37.8C recorded in Heathrow on 31 July - the hottest day of the year so far, and the UK's third warmest ever.
Here's how temperatures are expected to change throughout the morning:
Met Office warns people not to get 'caught out' by soaring temperatures
People are being warned not to be "caught out" by soaring temperatures, with the UK expected to be hotter than some of Europe's top holiday destinations, including Ibiza and Tenerife.
The Met Office has warned that after a slightly cooler week people could underestimate the heat, which could cause dehydration and sunburn, especially among the most vulnerable.
Grahame Madge, a Met Office spokesman, said: "Everyone needs to be careful during this heatwave, especially on Friday, where we are going to see a dramatic rise in temperature in some parts, exceeding the heatwave threshold.
"After a slightly cooler week, people should make sure they aren't caught out. If you need to travel, keep hydrated and apply sunscreen; the chance of sunburn and dehydration will be much higher."
Public Health England issues heat-health warning
Public Health England (PHE) has issued a heat-health warning, with people advised to stay cool indoors by closing curtains that face the sun and ensuring pets or children are not kept in vehicles.
Ishani Kar-Purkayastha, consultant in public health at Public Health England, said: "This summer, many of us are spending more time at home due to Covid-19.
"A lot of homes can overheat, so it's important we continue to check on older people and those with underlying health conditions, particularly if they're living alone and may be socially isolated."
UK faces days of unprecedented heatwaveSweltering temperatures will bathe the UK in exceptional warmth from Friday, but meteorologists have forecast a heatwave like no other seen before, Emily Goddard reports.Highs of 37C are expected across southern and eastern parts, marking only the fifth time the country has seen such temperatures since records began.And this could be the first time the country sees that degree of heat twice in the same year, following last Friday’s high of 37C.Emma Salter, a meteorologist at the Met Office, said on Friday: “We’ve never had two days in the same summer where we’ve had 37C or more … Today it will be the first time ever that we’ve had a summer with two days of 37C. It is really hot.”Unlike last week’s flash-in-the-pan heatwave, this one is forecast to extend long beyond the end of Friday, with 36C expected on Saturday, 35C on Sunday and 34C on Monday and Tuesday.
Rising temperatures will make it 'highly dangerous' for people to be outside, health expert warns
A health expert has warned that the UK's rising temperatures, with Friday forecast to be the hottest day so far this year, will make it "highly dangerous" for people to be outside if more is not done to curtail climate change.
Ilan Kelman, Professor of Disasters and Health at University College London, said: "These temperatures are unfortunately in line with the expectations for heat under climate change, which is one of the most concerning health impacts.
"Without stopping human-caused climate change, these levels of summer heat and humidity will become regular, making it highly dangerous for us to be outdoors and even indoors without continual cooling.
"Air pollution can also worsen under heat with its knock-on health effects, such as for cancer and asthma.
"Irrespective of urban heat islands and natural climate variabilities, the human signal in climate change is showing in these heat patterns."
Elderly among most vulnerable to extreme heat
Elderly people are among the most vulnerable to hot weather, with advice telling them to contact neighbours if they are living alone, to try to stay indoors during the afternoon and to carry a bottle of water when out.
Caroline Abrahams, charity director at Age UK, said: "We want older people to continue to enjoy the warm weather but, if it becomes uncomfortably hot, we advise some sensible precautions, particularly for anyone who has breathing problems or a heart condition.
"It's a good idea to remain indoors during the worst of the heat during the day. It's also advised to wear thin, light clothing, drink plenty of fluids and to eat normally, but perhaps more cold food than usual, particularly salads and fruit which contain a lot of water and help us stay hydrated.
"We know that extreme heat can aggravate lung and heart conditions so our advice is to take care and if you are breathless, even after you have rested, to seek medical advice."
People enjoying the hot weather on Bournemouth beach in Dorset (Andrew Matthews/PA)
August odds on to be hottest ever
Coral has said this August is odds on, at 4-5, to be the hottest ever recorded in the UK.
"We now make this August odds on to become our hottest ever. It's going to be a scorching few days and that could tip it into a record breaking month," said Harry Aitkenhead, a spokesperson for the bookmaker.
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