A spell of exceptional heat is set to develop this week, with temperatures forecast to rise rapidly and potentially challenge or exceed long-standing June records.
With a Red Extreme Heat Warning issued for midweek and Amber warnings already in force across much of England and Wales, this is a significant and potentially impactful period of weather.
Temperatures will climb quickly from Monday, widely reaching the mid-30s Celsius in southern areas, before rising further through Tuesday. The peak of the heat is expected on Wednesday and Thursday, when highs could reach around 39°C in parts of southern England, with the possibility of locally higher values.
This week’s heat in context
While hot spells are not unusual in summer, conditions of this magnitude remain relatively rare, particularly in June. The current UK June temperature record stands at 35.6°C, last recorded in 1976 and 1957, and could be challenged during this spell.
Runs of very high temperatures are also uncommon. Historically, sequences of three consecutive days reaching 35°C have only occurred a handful of times, such as in June 1976, August 1990 and August 2020. Temperatures exceeding 37°C on consecutive days have been recorded only during the July 2022 heatwave.
More recently, June temperatures have reached or exceeded 34°C in 2017 and 2019, while last year’s peak was notably lower at 33.2°C.
⚠️⚠️🔴 Red weather warning issued 🔴⚠️⚠️
— Met Office (@metoffice) June 22, 2026
Extreme heat across parts of central/southern England and Wales
Wednesday 0900 - Thursday 2100
Latest info 👉 https://t.co/QwDLMfRBfs
Stay #WeatherAware ⚠️ pic.twitter.com/IwXnyU1E7y
Why the heat feels more intense
This period of heat is expected to feel especially oppressive due to high humidity levels. Overnight temperatures will remain elevated, with widespread tropical nights likely across southern areas, where temperatures stay above 20°C.
Humidity plays a key role in how we experience heat. When moisture levels in the air are high, it becomes more difficult for the body to cool itself through sweating. This increases the risk of heat stress and associated health impacts.
Forecast dew points around 22°C are particularly notable, indicating very humid conditions. For comparison, during the July 2022 heatwave, dew points were much lower in the single figures, meaning this event will feel more uncomfortable despite similar or slightly lower peak temperatures.
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Why thunderstorms develop in hot weather
Alongside the heat, there is also a risk of thunderstorms developing, particularly across central and southern areas.
Hot weather increases the amount of energy available in the atmosphere. As warm air rises, it cools and condenses, forming towering clouds that can develop into thunderstorms. When combined with moisture and atmospheric instability, this can lead to heavy downpours, lightning and gusty winds.
These storms can form quickly and be highly localised, bringing sudden changes in conditions and, at times, intense rainfall.
Although the peak of the heat is expected midweek, temperatures are likely to ease slightly by Friday, though still remaining well above average for many areas.
With very high temperatures, elevated humidity and a risk of storms, this is a period of weather that stands out both for its intensity and its potential impacts.
Keep up to date with weather warnings, and you can find the latest forecast on our website, on YouTube, by following us on X and Facebook, as well as on our mobile app which is available for iPhone from the App store and for Android from the Google Play store.
