Highs of up to 31C have been forecast for this week as temperatures across the UK continue to rise.
A yellow heat health alert has been issued by the UK Health Security Agency (UKHSA) and Met Office for most of England, with all but the North East included in the warning.
The alert will come into force from Monday morning and remain in place until Thursday afternoon.
Liam Eslick, a meteorologist at the Met Office, said Monday will see mostly dry weather with “plenty of sunny spells” and a maximum temperature of 28C.
On Tuesday, conditions are expected to become cloudy and murky in western Scotland and Northern Ireland. Some showers will be seen across northern England which could turn thundery, but the rest of the country will see “more sunshine” and temperatures up in the mid to high 20s.
Mr Eslick said Wednesday is likely to be the warmest of the days so far with highs of 30C in the South East.
However, Thursday is likely to see a breakdown in the weather with clouds and outbreaks of rain forecast across the country. The meteorologist said there is even the possibility of an “odd thunderstorm for some”.
Temperatures on Thursday are expected to remain “widely warm” with some areas seeing highs of up to 31C.
Festival-goers at Glastonbury will have to wait a little longer for more clarity on the outlook for the weekend, though conditions are expected to remain unsettled as temperatures drop back to the average for June.
This is likely to be around 18C or 19C.