More than a month's rain fell in a few hours as the great British summer became a washout.
Parts of the UK were hit by storms and battered by heavy showers which resulted in flooding - but the weekend is set to bring settled weather.
Met Office forecaster Marco Petagna said: "We saw some parts of the South East, especially towards Kent, seeing up to 40mm of rain in one hour, and totals up to about 70mm across parts of Sussex and Kent, so two to three inches.
"The average monthly rainfall for Kent is about two inches, so more than a month's rainfall fell in a few hours yesterday."
It will remain "unsettled" overnight, with rain continuing to batter northern England, southern Scotland, across Wales, the West Midlands and down towards parts of the South West.
The South East will become drier this morning, Mr Petagna said.
After a dry, murky start towards the South East in the morning, there will be outbreaks of rain pushing in from the West, and while it might brighten up in places, there is a risk of heavy showers.
"The main trend through the day is for the rain to gradually push its way eastwards with brighter fresher conditions starting to move in from the west and that sort of sets the scene really for the weekend.
"A much quieter spell of weather - a lot of dry bright weather around this weekend. A few showers, mainly towards the north and west, but a lot of dry weather this weekend. Certainly a fresher feel to the weather compared to the last couple of days," the forecaster said.
Earlier, a weather warning was issued for parts of the country after torrential downpours and thunderstorms increased the likelihood of flooding.
The Met Office upgraded its yellow warning to amber for the east and south east of England after more than a month's rain fell in just nine hours. That warning has now expired.
On average, 51.6mm of rain falls throughout the entire month of August.
According to the Met Office, Eastbourne town centre saw 60mm of rainfall between 3am and midday on Thursday, with the majority of it falling in the last two hours.
East Sussex, and in particular Brighton, appears to have been hit by the worst of the storms, with many taking to social media to post photos of calf-high water running through the street.
Between 4.05am and 12.50pm on Thursday, East Sussex Rescue Service was called to 32 reports of flooding, some including water affecting electrics.
Kent firefighters attended two properties in the Ashford area following lightning strikes, although no one was reported injured.
At one property in Great Chart, a fire was put out by crews and they also responded to flooding in New Romney, Canterbury and Tunbridge Wells.
The Airbourne airshow in Eastbourne cancelled its flying displays for the day because of the heavy rain and Eastbourne's Arndale shopping centre had to be evacuated because of flooding, but later reopened.