According to the weather maps, areas around Bedfordshire, Cambridge and Essex will witness the hottest temperatures with a highs of 27C, the maps show. Areas closer to London, Surrey, Oxford and Buckinghamshire will bake at 26C. The Met Office’s outlook for Sunday to Tuesday reads: “Rain spreads southeast, heaviest in western Scotland. Brighter conditions follow with showers, some heavy and thundery. Windy at times. Very warm on Sunday, then turning cooler for the coming days.”

The UK has experienced its hottest summer on record, with provisional Met Office figures showing that the average temperature across June, July and August reached 16.5C, the highest since records began in 1884.

The unprecedented season followed an exceptionally warm spring and featured prolonged periods of extreme heat, including five major heatwaves and a record-breaking 40 days where temperatures exceeded 30C, comfortably surpassing the previous high of 34 days.

Met Office researchers said climate change was a key factor behind the exceptional conditions, estimating that human-driven global warming made the summer’s extreme heat around 130 times more likely.

Dr Amy Doherty, who leads the National Climate Information Centre at the Met Office said: “The conditions we’ve seen this summer have broken UK climate records once again. These records are now breaking with increasing frequency, reflecting the influence of human-induced climate change on the temperatures we’re experiencing in the UK.

“Particularly notable is how much we’ve exceeded the previous summer mean temperature record, set just last year. The figures also knock the infamous summer of 1976 down to seventh for average summer mean temperature, with the top five warmest summers all occurring since 2003.”

Jo Farrow, a meteorologist with Netweather.tv, wrote in the weather blog: “The weekend low pressure will miss most parts of the UK as its progress is stalled by a ridge of high pressure.

“This allows a fine, warm and sunny Saturday, and as the low surges northwards, the warm front rain will reach western Scotland, with the cold front over northwestern UK later on Sunday.

“By Sunday morning, the trailing warm front will bring more cloud to Scotland and Northern Ireland, but patchy rain in the north and west.

“Very warm and sunny for England and Wales and parts of Scotland. By the afternoon, there will be clusters of showers, from the cold front in the west, but also a scattering over South East Britain. So not entirely dry but fine for many parts, and temperatures potentially reaching 29C.”