The Government has issued 11 new guidelines during the 40C red alert heatwave as a "national emergency" is officially declared.
The UK Health Security Agency has increased its heat health warning from level three to level four, which is reached "when a heatwave is so severe and prolonged that its effects extend outside the health and social care system."
It adds "at this level, illness and death may occur among the fit and healthy, and not just in high-risk groups."
A Level 4 alert has been issued for the first time since the Heatwave Plan for England was introduced in 2004.
The Government’s Level 4 alert indicates that a severe heatwave could have impacts beyond health and social care with potential effects on transport systems, food, water, energy supplies and businesses.
UKHSA will continue to monitor any heat-related illness and work closely with the Met Office, the NHS and other government departments to assess the impacts of this hot weather.
Official Government guidelines for staying safe in hot weather:
- Look out for those who may struggle to keep themselves cool and hydrated – older people, those with underlying conditions and those who live alone are particularly at risk
- Stay cool indoors by closing curtains on rooms that face the sun – and remember that it may be cooler outdoors than indoors
- Drink plenty of fluids and avoid excess alcohol
- Never leave anyone in a closed, parked vehicle, especially infants, young children or animals
- Check that fridges, freezers and fans are working properly
- Try to keep out of the sun between 11am to 3pm, when the UV rays are strongest
- Walk in the shade, apply sunscreen and wear a wide-brimmed hat, if you have to go out in the heat
- Avoid physical exertion in the hottest parts of the day
- Make sure you take water with you if you are travelling
- Take care and make sure to follow local safety advice if you are going into the water to cool down
- Check medicines can be stored according to the instructions on the packaging.
Dr Agostinho Sousa, Head of Extreme Events and Health Protection at the UK Health Security, agency said: “We are likely to reach record temperatures at the start of next week, and it’s important we all know how to stay well in hot weather.
"Check up on vulnerable friends, family and neighbours to make sure they stay hydrated, keep cool and know how to keep their homes cool.”
Meteorologists gave an 80% chance of the mercury topping the UK's record temperature of 38.7C (101.7F) set in Cambridge in 2019, with the current heatwave set to peak on Tuesday.
There is currently no public health risks for schools - which are set to remain open during Monday and Tuesday - as urban heat will make it difficult for people to sleep at night as temperatures rise.
Some parts of Scotland and Northern Ireland will see temperatures in the day slightly drop but they're still on course to be extremely hot.
Professor Penny Endersby, Chief Executive at the Met Office, said: “This is the first time we have issued a Red National Severe Weather warning for Extreme Heat and the first time 40c has been forecast in the UK.
"In this country we’re used to treating a hot spell as a chance to go and play in in the sun. This is not that sort of weather.
“We have seen when climate change has driven such unprecedented severe weather events around the world that it can be difficult for to make the best decisions because noting in our life experiences has led us to know what to expect.’’
Jake Kelly, of Network Rail, warned that journeys will take "significantly longer and delays are likely as speed restrictions are introduced to keep passengers and railway staff safe", urging people to travel only if absolutely necessary on Monday and Tuesday.
Downing Street said that that Cobra met on Thursday amid the heatwave, and discussions with sectors including the NHS will "continue to work closely with all of those sectors over today, through the weekend and into early next week".
Meanwhile, motorists have been advised to try to make their journeys outside of the hottest periods of the day, particularly if they have older cars.
Sean Sidley, AA patrol of the year, said: "There are reports of road gritters being out this weekend to reduce the chances of our roads melting.
"If it does get sticky on the roads there's nothing worse than being stuck in a jam with the mercury rising, so make sure you carry plenty of water - at least a litre per person - and sufficient fuel, or if you're driving an electric vehicle (EV) - make sure you have plenty of charge so you can use the air-conditioning when needed."
Tim Doran, from the RNLI Water Safety Team said the service was anticipating a "busy weekend" for its lifeboat crews and lifeguards.
"If you are planning on going to the beach, we would encourage you to visit a lifeguarded beach and swim between the red and yellow flags," he said.
