The UK Health Security Agency (UKHSA) issued a Yellow Heat-Health Alert covering the East Midlands, East of England, London and the southeast of England, the Met Office announced on 17 June 20261. The Met Office said the alert means temperatures could lead to impacts on the health and wellbeing of some people, and that it runs from Wednesday 17 June and remains in place until Monday1. An earlier Met Office bulletin gave the start as 15:00 on Wednesday 17 June 2026 and the end as 20:00 on Monday 22 June 20262.
The Met Office forecast temperatures reaching the high 20s Celsius quite widely, with the potential for 32°C in the south of England on Sunday and possibly higher on Monday1. Its headline maxima for the period were 32°C on Friday in East Anglia, 28°C on Saturday, 32°C in the south and southeast on Sunday and the potential for 33°C in the same areas on Monday1. It said some areas in the south and southeast were likely to see heatwave criteria met by Saturday and more widely on Sunday1. Alongside the warmth it forecast spells of rain, particularly across northern and western areas, and a slight chance of thunderstorms across southeastern England1.
The Met Office defines a heatwave as a location recording at least three consecutive days with daily maximum temperatures meeting or exceeding the heatwave temperature threshold, which varies by county1. It said the two alerting systems serve different purposes: the UKHSA Heat Health Alert system is an England only service graded at yellow, amber and red levels, while the Met Office National Severe Weather Warning Service is UK wide3. The Met Office said an alert can be issued even when temperatures are not exceptionally high, but conditions are still likely to pose risks, and that very warm nights can reduce the body's ability to recover, raising the potential for heat-related illness3.
"A Yellow Heat-Health Alert has been issued by the UK Health Security Agency (UKHSA), which means temperatures could lead to impacts on the health and wellbeing of some people."
Why it matters for households
The alert covers the East Midlands, East of England, London and the southeast of England, and applies to health and social care settings in England; the Met Office describes the UKHSA system as an England only service1. The Met Office advises people heading to the coast to be mindful that sea surface temperatures are not as high as they would be in mid-summer1. It points to water safety advice on its website and in its app, which it says now features a dedicated beach forecast with tide times, wave heights and sea-surface temperatures, as well as guidance on UV and pollen levels1. The Royal Life Saving Society UK has free water safety resources available as part of drowning prevention week1.
What happens next
The Met Office said the warmest conditions are likely into early next week, when temperatures could peak again across southern and southeastern England on Monday and Tuesday, with uncertainty over how quickly conditions will begin to cool thereafter1. It said the latest forecast is available on its website, on YouTube, on X and Facebook, and on its mobile app1.
Households can read how the alert levels work in the guide to Heat-Health Alerts: Yellow, Amber and Red Explained, find background on the issuing body in The UK Health Security Agency: Alerts, Outbreak Advice and Local Teams, and see how to sign up for heat-health alerts.
Sources (3)
- Heatwave conditions forecast for parts of the UK this weekend as temperatures rise - Met Office, metoffice.gov.uk
- Climbing temperatures and potential thunderstorms - a week of contrasting conditions - Met Office, metoffice.gov.uk
- Heat alerts explained as Europe faces extreme temperatures - Met Office, metoffice.gov.uk
Heat-Health Alerts Explained
UK Health Security Agency
