The Met Office has warned of torrential rain and thunder in parts of Britain.
Some regions are expected to receive the equivalent of two weeks’ worth of rain in less than an hour on Tuesday. There were 78 flood warnings and 191 flood alerts across the country by 7.30am.
“There is a yellow warning in place in south-west Scotland until 10am on Tuesday morning,” the Met Office meteorologist Marco Petagna said. “For southern England and Wales the yellow warning is in place until 8pm.”
Derbyshire fire and rescue service said officers rescued an adult and a child trapped in a vehicle caught in floodwater in Bretby, near Burton upon Trent, at about 8pm on Monday
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At about 9pm, crews from North Yorkshire fire and rescue service went to the aid of a woman in a car stuck in floodwater in Cattal Moor Lane, near York.
Photographs taken at the Ship Inn pub in Mevagissey, Cornwall, on Monday night show floodwater inside the pub and nearby roads submerged.
The Environment Agency said a combination of a high tide, due at 8.40am on Tuesday, and predictions of force six north-westerly winds could result in flooding.
People are being told to leave caravans and properties in the area between 7am and 10am on Tuesday and not to return until it is safe to do so. They have been urged to take with them any medication, pets and anything urgent they might need over the next 48 hours.
The public are also being advised to take care along beaches, promenades, coastal footpaths and roads as large waves and sea spray could be dangerous.
In the south-west, the Environment Agency told people to avoid the seafront and check flood warnings with high tides and winds forecast.
On Tuesday, it said heavy showers could bring a “small chance of fast-flowing or deep floodwater causing danger to life”.