The national park, which straddles eastern California and Nevada, was hit by 1.46in (3.71cm) of rain in one area - around 75% of what it typically gets in a whole year.

It was also more than has ever been recorded for the entire month of August.

Since 1936, the only single day with more rain was 15 April 1988, when 1.47in (3.73cm) fell, park officials said.

While there were no immediate reports of injuries, officials confirmed around 500 visitors and 500 park workers were stuck inside the park, and roughly 60 vehicles have been buried in mud and debris.

"Entire trees and boulders were washing down," said photographer John Sirlin.

"The noise from some of the rocks coming down the mountain was just incredible."

He had witnessed the flooding while trying to capture photos of lightning as the storm approached.

"It was more extreme than anything I've seen there," added Mr Sirlin, who has been chasing storms since the 1990s.

"There were at least two dozen cars that got smashed and stuck in there," he said, adding that he did not see anyone injured "or any high water rescues".

During Friday's rainfall, large rubbish containers were pushed into parked cars, which caused vehicles to collide into one another, the park said in a statement.

"Additionally, many facilities are flooded, including hotel rooms and business offices," it added.

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Residents have also been left without water after a supply line that was being repaired broke and caused the system to fail.

The storm followed another major flooding event earlier this week at the park 120 miles northeast of Las Vegas.

On Monday, some roads were closed after they were inundated with mud and debris from flash floods that also hit western Nevada and northern Arizona.