The Environment Agency said that rain falling on already saturated ground could lead to more rivers breaking their banks and causing buildings to flood.
More than 70 flood warnings are in place, mainly in south-west
England, the Midlands and Scotland, with 173 less serious flood alerts across England and Wales.
John Curtin, the agency’s head of incident management, said: “We ask that people stay safe by staying away from swollen rivers and not attempting to drive through flood water.”
The Met Office issued an amber warning across much of South Wales and South West England which means people should “be aware” of bad weather.
A spokesman said: “Coming so soon after the heavy rain which fell in many places on Wednesday, this is likely to provoke further issues with flooding.”
Much of Britain suffered severe winds and there were gusts of up to seventy miles an hour in Capel Curig in Wales.
In Sparkhill in Birmingham, several cars were damaged when the roof was blown off a mosque.
An elderly pedestrian was treated for a cut to his head after being struck by a tree which also brought down a lamppost in Perry Barr, Birmingham.
Meanwhile, two teenage girls were taken to hospital after an incident in Wollaston, Stourbridge.
A fallen oak tree narrowly missed a house in New Quay, Cardigan Bay, and resident James Trott said: “It has smashed our fence down and our dogs are going crazy.”
In Northamptonshire, about a thousand people had to leave their holiday homes at Billing aquadrome alongside the River Nene which burst its banks.
A spokesman for the holiday park said: “The most important thing to us is the safety of our holiday home owners, holiday guests and staff.”
Rail services between Devon and Somerset were badly hit and a First Great Western spokesman said lines could be closed for up to two more days.
About five hundred homes in Dumfries and Galloway lost power after a lightning strike and the mobile phone network was also affected.
MINOR UK
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