UK records hottest June day as red heat warning grips country

The UK recorded its hottest June day on June 24, 2026, after provisional Met Office data showed 35.8C at Wiggonholt in West Sussex.

The reading broke the previous June high of 35.6C, set in Camden Square in 1957 and matched in Southampton in 1976. It came while a rare red extreme heat warning remained in force across part of England, with further amber warnings also reported for later in the week.

Record heat

The new high was confirmed as the heatwave intensified and authorities warned that conditions could become dangerous even for people who are usually healthy. The June record now sits below only the UK's all-time temperature high of 40.3C, recorded in Coningsby, Lincolnshire, on July 19, 2022.

The Met Office had already warned that temperatures could challenge long-standing June records. By June 24, the forecast had become reality, with multiple outlets citing provisional official data showing the record had been broken.

Red warning in force

The red extreme heat warning was in place from Wednesday morning through Thursday evening, reflecting the scale of expected disruption and the seriousness of the health risk. Red heat warnings are rare in the UK and are reserved for severe impacts beyond ordinary summer heat.

The warning came as the UK Health Security Agency and health officials urged caution around prolonged exposure, dehydration and the strain hot weather can place on vulnerable people, older adults and those with medical conditions. The severity of the alert also underscored pressure on services that rely on staff, power and transport moving normally.

Disruption across daily life

Reports on June 24 described widespread disruption across schools, transport and public services. The Guardian said schools, hospitals, care homes and workplaces were struggling to cope with the heat, while also reporting slower trains, school closures and hosepipe bans.

The Times reported that the London Ambulance Service deployed more than 400 extra crews. That reflected the strain extreme heat can place on emergency response during the busiest hours of the day, especially when callouts rise and crews must work in difficult conditions.

AP said the UK record formed part of a wider heat dome affecting western Europe, with transport and daily routines being disrupted across the region. The broader picture was not just a single hot afternoon, but a multi-country event affecting movement, health advice and normal summer operations.

Climate and health context

The Guardian quoted Met Office chief scientist Stephen Belcher as describing the June heat as sobering and linking the event to climate change impacts. The scale of the heat, combined with the red warning, made the episode stand out even in a country that has seen repeated summer heat extremes in recent years.

WHO Director-General Tedros Adhanom Ghebreyesus was also quoted warning that the European heatwave was putting lives at risk. The comments reflected the public health concern that emerges when sustained heat affects large populations at once, especially when it reaches levels that can overwhelm homes, schools, transport and care settings.

For the UK, the event is another reminder that hot spells are becoming more consequential as infrastructure and public services are tested by temperatures well beyond seasonal norms. The impact is not limited to discomfort. It can affect rail reliability, school operations, emergency response, water use and workplace safety.

What happens next

Attention now turns to whether the provisional 35.8C reading is finalized or revised by the Met Office. Officials are also expected to keep updating advice as the warning period ends and as any later amber alerts continue.

Key questions remain over whether the red warning will be extended, downgraded or replaced after Thursday, and how many schools, hospitals, rail services and other employers will continue to report disruptions. The weather may shift quickly, but the immediate consequences of the record heat are already clear.

June 24 has now joined the UK weather record books. The more immediate story, though, is the way the heat has moved from forecast to public health risk, and from there into the daily routines of schools, hospitals, rail passengers and emergency crews.