The UK is expected to get even hotter with temperatures predicted to reach a sizzling 32C (89.6F).
Records were set in both England and Wales on Sunday, and the mercury is forecast to climb even higher on Monday.
In England on Sunday, 31.6C (88.88F) was recorded in Heathrow, overtaking Saturday’s record-breaking 30.3C (86.54F) recorded in Coton in the Elms, Derbyshire.
Wales recorded 30.2C (86.36F) in Cardiff, compared with 29.6C (85.28F) reached in Usk, Monmouthshire, on Saturday.
The Met Office said temperatures could climb to a maximum of 32C in London and the South East of England on Monday, adding that there is a low chance of isolated heavy showers in the afternoon.
The long range forecast for next weekend suggests spells of rain or showers are likely for many areas, with temperatures easing back closer to normal.
Forecasters also warn that some heavy rain or thunderstorms are possible.
Tens of thousands of people headed for beaches over the weekend with roads busy on coastal routes.
Saturday had marked the hottest day of the year for all four nations, and the hottest day since records began for Northern Ireland with 31.2C (88.16F) recorded in Ballywatticock, in Co Down, beating the previous highest temperature of 30.8C (87.44F), which was reached on July 12 1983 and June 30 1976.