Monday is expected to be the best weather of the long weekend, the Met Office said.
Bank holiday Monday will see a mix of sunny spells and showers that could become heavier with thunder, the Met Office said.
Monday is expected to be the best weather of the long weekend, after festivalgoers braved the rain and mud in plastic ponchos on Saturday and Sunday.
It comes as Bradworthy Common in Devon saw 34.2mm of rain over 12 hours on Sunday, more than a third of the average for Devon for August, according to the Met Office.
And a flood warning was in place for Spadesbourne Brook at Bromsgrove, Worcestershire, on Sunday night, meaning flooding is expected, while 15 areas were covered by Environment Agency (EA) flood alerts, meaning floods are possible.
Met Office senior operational meteorologist Dan Stroud said: “It’s another day of sunny spells and showers, a generally bright but cloudy start with sunny spells in the east, we will have some showers from the get-go in the west and they will become a bit more heavy, the odd rumble of thunder is possible.
“A drier and brighter end to the day.
“Monday promises to be the best of the three days, still showers around but a lot less than what we’ve seen.
“Tuesday across England and Wales promises to be reasonably fine with some lengthy sunny spells. It’s a different story across Scotland. we’ve got a band of cloud and rain.
“Wednesday, it changes, it goes downhill, turning cloudy and wet during the course of Wednesday, particularly across Wales and northern England northwards.”
It comes after music fans at Reading Festival donned ponchos and umbrellas, and frolicked in the mud after getting caught in downpours over the weekend.
While some were seen flinging mud at each other and playing in puddles, others hid beneath their plastic ponchos as they braved the poor weather conditions.
Elsewhere, the cricket at Lord’s in London was halted by the rain on Saturday.
Festivalgoers heading to Reading and Leeds, Creamfields and other live music events had previously been warned of unseasonably strong winds.
It comes after continued hot weather across the UK, which coincided with extremely dry conditions.
The Met Office has previously said the UK is on course for its hottest summer on record after five heatwaves, with temperatures of up to 38.1C recorded in London.
