A rare red weather warning for extreme heat has come into force across parts of England and Wales, with temperatures expected to approach the UK record of 40.3°C. The Met Office warning covers an area from London to Swansea and Somerset to Birmingham from 9am Wednesday to 9pm Thursday.
Temperature Forecast and Record Potential
Temperatures could climb to 40°C on Wednesday and Thursday, potentially surpassing the June record of 35.6°C set in Hampshire in 1976. The UK's all-time high of 40.3°C, recorded in Lincolnshire in July 2022, may also be threatened. Met Office spokesman Grahame Madge said: "The Met Office is flagging 39°C as a headline maximum temperature on Thursday, most likely for somewhere in London or the South East. It is possible we could see temperatures higher than the 39°C if the final values are at the upper end of our narrow range."
On Tuesday, the highest temperature logged was 34.6°C in Wisley, Surrey, according to the Met Office.
Health Alerts and Public Impact
Red heat health alerts issued by the UK Health Security Agency (UKHSA) are in place from 1am Wednesday to 11pm Thursday for the East of England, East Midlands, London, South East, South West, and West Midlands. Amber alerts cover the North East, North West, and Yorkshire and The Humber. The alerts mean "adverse temperatures are likely to impact on the health and wellbeing of the population."
The combination of extreme heat and high humidity could impact public health, infrastructure, power and water supplies, the Met Office warned. Madge added: "It is important to remember that the temperature value is only one element of this extreme heatwave story. The other major factor is the high humidity, which for many will make the intense heat even harder to endure."
School Closures and Transport Disruption
Almost 100 schools in Somerset will be fully closed on Wednesday and Thursday, according to Somerset Council. Around 100 schools in Buckinghamshire and 86 in Gloucestershire will be at least partially closed, council data shows. Some schools have allowed pupils to wear PE kit instead of full uniform.
Transport bosses have urged people to avoid travel on Wednesday and Thursday. Avanti West Coast plans to run fewer services, warning of "a risk of further disruption." Chiltern Railways has axed more than half its services until Friday "to ensure the safe operation of the railway." Eurostar cancelled four trains between London and Paris on Wednesday and Thursday "due to expected adverse weather."
Safety Measures and Government Response
The London Fire Brigade advised against disposable barbecues in parks, as "they pose a significant fire risk." NHS trusts advised patients attending appointments to bring water and check travel. The Cabinet Office held an official-level COBR meeting on Tuesday morning and will continue to monitor the situation, a Government spokesman said.
Mayor of London Sir Sadiq Khan triggered a "high" air pollution alert for Wednesday, the third this year. The Army cancelled ceremonial operations in London and Windsor to protect soldiers' wellbeing. Natural Resources Wales released extra water into the River Dee to reduce fish deaths.
