The Red Extreme heat national severe weather warning will cover Monday 18 and Tuesday 19 for parts of central, northern, eastern and southeastern England. An Amber Extreme heat warning, has been in place for much of England and Wales for Sunday, Monday and Tuesday (17 – 19 July) since earlier this week. Amber areas have also been extended to cover Cornwall, west Wales and parts of southern Scotland.

According to the HSE, the law does not state a minimum or maximum temperature, but the temperature in workrooms should normally be at least 16°C or 13°C if much of the work involves rigorous physical effort.