Met Office Extreme Heat Warning Expanded: UK Faces Up to 38°C — What to Know (June 2026)
The Met Office has expanded its amber extreme heat warning as the UK braces for highs that could reach up to 38°C between Monday 22 and Thursday 25 June 2026. The central forecast peaks around 35°C in the southeast, but forecasters say there is growing confidence the week could break the June record of 35.6°C, set in Southampton in 1976. Here’s what is actually forecast, who is most at risk, and how to stay safe.
How hot will the UK get, and when?
The Met Office forecasts temperatures peaking around 35°C on Tuesday and Wednesday, with 38°C as an upper-end ceiling rather than the central forecast. According to the Met Office’s deputy chief forecaster, temperatures are forecast to reach 32°C on Monday, climbing to 35°C on Tuesday and Wednesday, before dropping slightly to a peak of 34°C more confined to the southeast by Thursday.
The day-by-day forecast peaks, with the key reference points:
| Day | Forecast peak | Notes |
|---|---|---|
| Monday 22 June | ~32°C | Heat builds across the south |
| Tuesday 23 June | ~35°C | Joint hottest; humid |
| Wednesday 24 June | ~35°C | Joint hottest |
| Thursday 25 June | ~34°C | Confined to the southeast |
| June record | 35.6°C | Southampton, 1976 |
| Upper-end ceiling | 38°C | Possible, not central forecast |
A crucial detail is the heat overnight. The Met Office warns of tropical nights — where the temperature doesn’t drop below 20°C — which are likely in urban areas and are a major driver of health impacts, because the body gets no chance to cool down.
Where is the extreme heat warning in force?
The amber extreme heat warning runs from Monday 22 June to Thursday 25 June 2026, and was expanded on Sunday to cover more of the country. Monday and Tuesday’s warning covers most of southern England, central and eastern Wales, and much of the Midlands, while Wednesday and Thursday’s alert extends further still.
Conditions are different in the northwest, which stays cooler and cloudier with some light rain — this is not a UK-wide heatwave, but one concentrated in the south and east.
What are the health alerts, and who is at risk?
The UK Health Security Agency (UKHSA) has issued an amber heat-health alert — its first amber alert escalation of the period — for several regions of England. An amber heat-health alert is in place for the East of England, South East, South West and London, with a yellow alert for the West and East Midlands, in force until 8pm on Tuesday 23 June.
Here’s what the alert levels cover:
| Alert | Regions | Meaning |
|---|---|---|
| Amber (heat-health) | East of England, London, South East, South West | Likely health impacts across the wider population; rising demand on health services |
| Yellow (heat-health) | West Midlands, East Midlands | Impacts mainly for vulnerable groups |
UKHSA’s head of extreme events warned that sustained warm weather can result in serious health outcomes, especially for older adults. The groups most at risk are older adults, young children, and people with underlying heart or respiratory conditions.
How to stay safe in the heat
The official UKHSA advice is to keep your home cool, stay out of the sun during the hottest hours, and check on vulnerable people. The specific guidance:
- Keep your home cool by closing windows and curtains in rooms that face the sun during the day.
- Avoid direct sunlight between 11am and 3pm, when UV levels are highest; if outside, cover up, wear a hat and sunglasses, and apply sunscreen.
- Time physical activity — exercise or dog walks — for the cooler morning or evening.
- Check on older relatives and neighbours, and those with health conditions.
- Take care near water. At least 15 people died after getting into trouble in open water during a hot spell in May; sea and lake temperatures remain cold even when the air is hot, risking cold water shock.
Is this part of a wider European heatwave?
Yes — this is the second European heatwave of 2026, and parts of the continent are hotter still. Heat warnings are in place across much of Europe, with temperatures forecast to reach around 40°C in regions of Spain, France and Italy. Germany is approaching 38°C and several Italian cities are set to hit 40°C for the first time this year.
For context on how the UK compares this week:
| Country | Forecast peak |
|---|---|
| UK | ~35°C (up to 38°C) |
| Germany | ~38°C |
| Spain / France | ~40°C |
| Italy | ~40°C |
The bottom line
The headline figure is up to 38°C, but the realistic central forecast is a peak around 35°C on Tuesday and Wednesday in southeast England — enough to challenge the 1976 June record of 35.6°C. The amber warnings run 22–25 June, with the biggest risks coming from humidity, warm nights, and water safety. Check the Met Office and UKHSA for the latest, as cloud and thunderstorm risk could change the highest temperatures as the week develops.
This article reflects forecasts and official warnings as of 21 June 2026 and may be superseded as conditions change. Follow the Met Office and UKHSA for the latest alerts.