The UK could have its hottest day on record this week, with temperatures forecast to hit up to 41C (106F).
The Met Office has issued a red extreme heat warning on Monday and Tuesday in much of England, from London and the south-east up to York and Manchester.
The current highest temperature in the UK is 38.7C, in Cambridge in 2019.
High temperatures are also forecast across the UK – with amber warnings in the rest of England, all of Wales, and parts of Scotland.
London is set to be one of the hottest places in the world on Monday, with temperatures soaring above the Western Sahara and the Caribbean.
The capital is forecast to be hotter than Dakhla in Western Sahara (24C), Nassau in the Bahamas (32C), Kingston in Jamaica (33C), Malaga in Spain (28C) and Athens in Greece (35C).
The hot weather will continue on Tuesday – with overnight temperatures warned to be in the mid twenties – before cooling on Wednesday.
It is the first time the Met Office has issued a red warning since the system was introduced last year.
It means “widespread impacts on people and infrastructure” are expected, with “substantial changes in working practices and daily routines” required.
Some schools plan to close early – or not open at all – although the government has issued guidance designed to keep them open.