In the UK, temperatures are expected to hit 40C for the first time since records began.
The Government there has declared the first ever red warning for heat, meaning there is a danger to life and a threat to major travel disruption.
The UK's Met Office reported Monday was the hottest day of 2022 for the country so far, after temperatures hit 38.1C in Suffolk.
Flights were halted at two airports after the heat effectively melted the runway, and some hospitals had to cancel surgeries because operating theatres were too hot.
London correspondent Olly Barratt spoke to Corin Dann.