More than 100 people had to be rescued after downpours battered the UK, with two weeks of rain falling in one hour.
The deluge turned roads into rivers, leaving emergency services battling to reach trapped motorists.
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The monsoon-like weather swept in from Northern Ireland where cars were washed away, bridges collapsed and Derry airport had to be closed.
Emergency services there received a call every 45 seconds as 50mm of rain hammered down.
The storm then blew across northern England causing havoc before giving the North Yorkshire coastal towns a good soaking.
People Saltburn-by-the-sea in North Yorkshire were hit by thundery rain on Wednesday
There was panic in York with people fearing a repeat of the floods of 2015.
Residents were left under water yet again. One tearful woman said: "It came through like a tidal wave."
In the Bramham Park area of Leeds, around 40mm of rain fell between 10am-11am. The average for August is 77.2mm.
Monsoon-like conditions were seen in nearby Scarborough
One racegoer shields herself with an umbrella in York
Early-bird campers arriving for the annual Leeds music festival had to wade through mud. Local Marcus Burton warned: "If you are coming to Leeds, bring a canoe."
Resident Samantha Last took pictures of water cascading into an Asda store in the city, advising: "Take your wellies if you are going shopping."
At Saltburn, by the sea in North Yorkshire, people battled along the town's pier.
And down the coast, Scarborough was one of the hardest hit.
Early arrivals battle deep mud after torrential rain at Leeds Festival
This car became stuck in the bog as revellers try to push it
Miles Jackson, from the Festival of Fun store, said: "The sky turned black, it was like it was midnight, then we had a deluge come down the street."
The Met Office's Nicky Maxey said the UK had already had around 96% of the expected rainfall for August.
She added that the forecast is for a North/South split going into the Bank Holiday weekend.
There will be sunshine and showers over much of the country today but tomorrow the South will stay fairly dry while the North could get showers, thunder and hail.