Temperatures have already climbed above 35C in some parts of England, on what could turn out to be the hottest day of the year so far.
The Met Office said that by midday temperatures had reached 36.4C at Charlwood in Surrey, while at Wisley temperatures had hit 35.1C, and a number of other spots were above 34C, including Westonbirt in Gloucestershire and Heathrow, West London.