The UK is set for stifling heatwave temperatures this week which could reach 40C and, with the Met Office issuing a red warning, some schools are easing uniform rules and may close13:14, 22 Jun 2026Some pupils may get an early summer holiday this week as brutal 40C temperatures could see schools close.‌The Met Office has issued a rare red weather warning for Wednesday and Thursday in the face of extreme heat and humidity. Amber warnings have also been issued.‌The weather forecaster said that in this week’s heatwave, parts of England and Wales are likely to see temperatures exceed 37C in the shade and could even see them rise to 38C to 40C in some places.‌Many schools have already said they will be relaxing uniform rules for children facing stifling conditions - while there is also the possibility of schools closing.Before the red warning was issued, the teaching union NASUWT said that if the amber alerts were upgraded then "school and college employers must ensure that an immediate, additional risk assessment is carried out".‌This "could include full or partial closure of the site", officials confirmed.Falkland Primary School in Newbury is one of the schools which will be relaxing its uniform rules to allow children to wear PE kits, while it is also waiting on advice over closure.It wrote on Facebook: "HOT WEATHER! With exceptionally high temperatures expected, children are very welcome to attend school in their PE kit this week (closed toe shoes must still be worn for health and safety reasons please).‌"We are currently awaiting advice from West Berkshire regarding any potential early closures should temperature forecasts hit 35+. Thank you."While St John Fisher Catholic High School, Wigan, said: "Due to the hot weather forecast this week, students are not required to wear their blazers or ties and may leave them at home. Students are also encouraged to bring a water bottle to school each day to help them stay hydrated. Thank you for your support, and please take care in the warm weather."‌And the Castle Rock School, in Coalville, Leicestershire, is relaxing its rules over ties but will still require kids to wear the uniform. "With the warmer weather this week, we want to make sure all students stay safe, comfortable and ready to learn. Students are welcome to attend school without blazers, grey jumpers or ties during the heatwave," it states."Please remember: Stay hydrated, Sunscreen. Please note: We recognise that schools may take different approaches during periods of hot weather. Our decision to keep students in standard uniform has been made following careful consideration. We are mindful that some students may have limited access to PE kit, and it is important that it remains available and suitable for PE lessons."As our PE kit is predominantly black, a light cotton school shirt is typically more comfortable for students during warmer weather. As always, our priority is to ensure all students are comfortable, included, and ready to learn."‌The extreme heat will be accompanied by high humidity, and very warm and humid nights which will make it hard for people to recover overnight, the Met Office said.The heat will have impacts on health, and there will be “significant disruption” to daily life, it warned, as it urged people to adapt their routines where possible to cope with the heat.The Met Office had already issued amber weather warnings covering large areas of England and Wales from Monday to Thursday. But an area stretching from London to Swansea and Somerset to Birmingham will now be covered by a red alert from 9am on Wednesday and 9pm on Thursday.‌NASUWT said: “A Met Office Red Alert indicates that it is very likely that there will be a risk to life, with substantial disruption to travel, energy supplies and possibly widespread damage to property and infrastructure. People should avoid travelling where possible and follow the advice of the emergency services and local authorities.“Where a Red Alert is issued for extreme heat, school and college employers must ensure that an immediate, additional risk assessment is carried out and the control measures indicated are enacted. These could include full or partial closure of the site if the risk assessment deems this necessary.“The risk assessment must also take account of travel to and from the site for learners and staff and the potential for disruption to public transport systems later in the day.”Article continues belowBut the Department for Education doesn't normally recommend closing schools in hot weather. It states: "During hot weather, we don’t normally advise schools to close."This is because school attendance is the best way for pupils to learn and reach their potential, and hot weather can usually be managed safely. School leaders should make sure they take any steps necessary to make sure children are safe and comfortable, and the heat-health alerts can guide this."