Red Extreme Heat Warning & Possible Temperature Records

London, 24 June 2026 – The UK Met Office has issued a Red Extreme Heat Warning for Wednesday and Thursday. Meteorologists expect that the current UK temperature record for the month of June could be broken in the coming days.

Since the beginning of the week, Amber Extreme Heat Warnings have been in effect across large parts of southern and central England, as well as much of Wales, and will remain in place until Thursday evening. Weather conditions are increasingly developing into an exceptional heatwave with far-reaching impacts on public health, infrastructure, and essential services.

Temperatures Could Reach 39°C

The peak of the heatwave is expected on Wednesday and Thursday. According to the latest forecasts, temperatures could rise to 39°C or even higher.

For comparison, the current UK June temperature record stands at 35.6°C, recorded in Southampton in June 1976 and in Camden Square, London, in June 1957.

Record Temperatures Also Possible in Wales

In addition to a new UK June record, Wales could also see its all-time June temperature record broken. The current Welsh June record is 33.7°C, set in 2000.

Scotland and Northern Ireland are also expected to experience exceptionally warm conditions. While new records are considered less likely there, meteorologists are forecasting temperatures between 28°C and 31°C.

Tropical Nights Increase the Heat Stress

Particularly challenging will be the unusually high overnight temperatures. Many parts of England and Wales are expected to experience tropical nights, where temperatures remain above 20°C even after sunset.

Urban areas will be especially affected, as densely built-up environments retain heat and significantly limit nighttime cooling.

High Humidity Creates Oppressive Conditions

In addition to the extreme heat, exceptionally high humidity levels are expected. Dew points could reach 22°C on Wednesday and Thursday.

Dew points of this magnitude make the air feel particularly humid and uncomfortable. According to the Met Office, some forecast values may even exceed those experienced during the historic July 2022 heatwave.

The combination of extreme heat and high humidity significantly increases the risk of heat stress and may pose health risks to people of all ages.

Impacts on Health, Infrastructure, and Water Supply

Authorities are warning of significant impacts across many aspects of public life. In addition to increased pressure on hospitals and emergency services, transport networks, energy supplies, and water systems could also face considerable strain.

Emergency responders are also expecting a rise in water rescue incidents as many people seek relief from the heat at beaches, lakes, and rivers.

Slight Relief Expected by the Weekend

A gradual easing of the heat is expected from Friday onward. Temperatures will decline somewhat but are still forecast to remain well above average, reaching around 32°C in eastern parts of the country.

Meteorologists are already describing the upcoming weather event as one of the most remarkable June heatwaves in British weather history.