Torrential downpours and storms are forecast to bring an end to the sunbathing this weekend, with warnings of flash flooding for some parts of the country.
The UK has basked in hot and humid weather this week, with temperatures expected to hit 32C (89.6F) degrees in some parts today.
But further storms and thundery weather is forecast for much of the country over the next 24 hours after storms hit overnight.
The Met Office has issued an amber warning of rain for England and east Wales for tonight through to Saturday.
It said "Several areas of heavy, thundery showers will develop over England and Wales from Friday night before moving northwards during Saturday.
"Not everywhere within the warning area will see thunderstorms, and indeed some spells of warm sunshine are expected at times, but where thunderstorms do form, some torrential downpours are likely with frequent lightning, large hail and locally strong gusts.
"Significant flooding is possible where these do occur from surface water as well as from small, fast-responding watercourses. The public should be prepared for the risk of disruption from any of these elements."
The Environment Agency warned 30mm of rain could fall in an hour in some areas during the torrential downpours, increasing the risk of localised and flash flooding.
Environment Minister Dan Rogerson said the EA was working closely with local authorities to prepare for any localised flooding.
He said: "Our priority is public safety. I urge people to be prepared and act on the advice from the Environment Agency and local emergency services."
John Curtin, director of incident management at the Environment Agency, said: "Intense heavy rainfall this weekend brings a surface water flood risk for England throughout the weekend. Flooding can happen very quickly and the public are urged to keep checking local weather forecasts and the Environment Agency website for information on a regular basis.
"We will continue to monitor the situation closely and support local authorities, who will respond to any reports of surface water flooding. We will also continue to monitor river levels closely and issue warnings where flooding is likely."
It comes after storms hit part of the country last night.
One woman had a lucky escape after lightning struck a few feet from where she was filming the storm from her bedroom window in the early hours..
Susannah Ford-Crush said her skin was left tingling after the strike, which hit scaffolding on a house next door around 3am.
The 34-year-old photographer, from Tunbridge Wells, Kent, said: "I couldn't sleep because of the storm so I decided to video it on my phone.
"There's some scaffolding on the house next to me and the lightening came down one of the poles and I got an indirect hit.
"It was a weird sensation. It knocked me back onto my bed and I felt a light burning sensation up my arm."
Meanwhile London Metropolitan Police's Air Support Unit tweeted pictures of the lightening saying "And here folks is why we are currently on the ground!! #SummerStorm"
Tom Tobler, a meteorologist with MeteoGroup, said today would be the hottest day of the year so far, beating yesterday's high of 29.2C (84.6F).
He said temperatures had reached 31C (87.8F) at London City Airport by 1pm.
"This afternoon, scattered showers across northern England and southern Scotland will move northwards. It should stay dry elsewhere with sunny spells. The south-eastern quarter of England will be mostly sunny, very humid and hot, with temperatures expected to reach 32C in places. Today will be the hottest day of the year so far, beating yesterday's high of 29.2C.
"Overnight, showery rain will move in from the south, turning heavy and thundery across southern England," he said.
"Tomorrow the heavy rain and thunderstorms will move northwards. Some sunny spells developing in the south after the rain clears, but there will be further thunderstorms in places later. Some torrential downpours likely in places."