UK braces for hottest day of heatwave as temperatures hit 35C

Temperatures in parts of England were forecast to reach 35C on Wednesday as a fourth heatwave of the year tightened its grip and amber heat health alerts stayed in force across several regions. The warning put older people, young children and anyone with underlying health conditions at higher risk, while outdoor workers, rail passengers and hospitals faced a fresh round of disruption.

The UK Health Security Agency said its heat-health alert service covers England only and is designed to warn health and social care professionals, along with others working to reduce harm from prolonged hot weather. Amber alerts were in place for the East Midlands, East of England, London and the South East, while yellow alerts covered the South West, West Midlands and Yorkshire and The Humber.

Health officials have repeatedly warned that heatwaves can put significant pressure on social care services and the National Health Service. That risk is rising after an unusually hot May and June, with the Met Office saying England had its hottest June on record and BBC Weather describing the current spell as one of the longest-lasting heatwaves since 1976.

The transport system has already shown how quickly extreme temperatures can cascade into disruption. National Rail says hot weather causes overhead lines to expand and sag, forcing trains to slow to avoid damage and, in some cases, leading to cancellations or diversions. Earlier heat broke rails between Coventry and Leamington Spa, suspending West Midlands Railway services on that stretch after a rail buckled in Leamington.

The latest alerts sit inside a wider pattern of repeated summer heat. July 2022 brought a major heatwave that set new temperature records, and the Met Office has used that spell as a benchmark in later heatwave reporting. This year’s repeated alerts have already covered much of England, including the East Midlands, East of England, London, South East, South West and West Midlands, underlining how often the country’s public services are now being asked to respond to dangerous heat.

The heat-health alert system was built to forewarn of periods of high temperatures that may affect public health. With Wednesday set to be the hottest day of the week, the test is no longer whether Britain can issue the warning, but whether hospitals, care services and transport operators can keep pace when the next 35C day arrives.