The August bank holiday record for highest temperature in the UK has been broken.
A recording of 33.3C (91.9F) was noted at Heathrow at around 2.30pm, the Met Office said.
The record before today was set in 2001, also at Heathrow, and was 31.5C (88.7F).
And forecasters say it is set to be at least as hot on Monday, likely matching 33C (91.4F) - most likely in the South East.
On Sunday afternoon, temperatures reached 27.1C (80.78F) in Hawarden, Wales, and 23.6C (74.48F) in Ballywattcock, Northern Ireland.
In Prestwick, Scotland, it reached 26.2C (79.16F).
It wasn't all clear skies, with the Rhyl Air Show having to be delayed due to the weather, with Denbighshire County Council saying an "unexpected sea fog" had hit the event and the visibility was not good enough for display flying.
The warm weather is the result of warm air being dragged up over the UK from France.
It comes at the end of what has been an often wet and cold August, with intense rainfall causing havoc with parts of the country's infrastructure such as the dam in Whaley Bridge.
On Saturday, the Met Office warned people to stay out of the sun as they predicted potentially record-breaking bank holiday temperatures.
A sunny bank holiday weekend sees Britons flocking outdoors to make the most of the last of the summer, including at big events such as Notting Hill Carnival as well as the Reading and Leeds Festival.
Public Heath England advice for coping with a heatwave includes: