Heatwave conditions forecast for parts of the UK

The Met Office announced on Wednesday 17 June 2026 that heatwave conditions are forecast for parts of the UK this weekend, with some areas in the south and southeast of England likely to see heatwave criteria met by Saturday and more widely on Sunday¹. The UK Health Security Agency (UKHSA) has issued a Yellow Heat-Health Alert covering the East Midlands, East of England, London and the southeast of England from Wednesday 17 June until Monday¹.

Temperatures are expected to reach the high 20s Celsius quite widely, with the potential for 32°C in the south of England on Sunday and potentially higher temperatures on Monday¹. The Met Office gives the following headline maximum temperatures for the period¹:

Southern parts of England are expected to approach 30°C by Friday, depending on cloud cover¹. Alongside the warmth there will be spells of rain, particularly across northern and western areas, and a slight chance of thunderstorms across southeastern England¹. The Met Office says 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 cool thereafter¹.

The Met Office sets out the official definition of 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. The Yellow Heat-Health Alert means temperatures could lead to impacts on the health and wellbeing of some people¹.

Deputy Chief Forecaster Gregory Wolverson said that many parts of southern and eastern England are likely to see temperatures high enough to meet heatwave thresholds, and that while temperatures may be high there is more cloud around than in May, with a chance of thunderstorms developing in places, particularly later each day, which could bring heavy showers and localised impacts¹. The Met Office also notes that much of central and western Europe is experiencing notable heat, which is helping to feed warmer air towards the UK¹.

Why it matters for households

The alert covers the East Midlands, East of England, London and the southeast of England and runs from Wednesday 17 June until Monday¹. The Met Office states that the alert means temperatures could lead to impacts on the health and wellbeing of some people¹. Heatwave criteria, as the Met Office defines them, are expected to be met in some southern and southeastern areas by Saturday and more widely on Sunday¹. The official definition and county thresholds set out how the three-day criterion is applied. The hot weather preparation checklist and the wider heatwaves and drought household guide cover practical preparation, and the heatwaves and drought hub collects the related guides.

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 free water safety resources from the Royal Life Saving Society UK and to water safety advice on its website and in its app, which now includes a dedicated beach forecast with tide times, wave heights and sea-surface temperatures, as well as guidance on UV and pollen levels¹.

What happens next

The Yellow Heat-Health Alert remains in place until Monday¹. The Met Office says the warmest conditions are likely into early next week, with temperatures possibly peaking again across southern and southeastern England on Monday and Tuesday, and uncertainty over how quickly conditions will begin to cool thereafter¹.