Heavy rain and strong winds are causing disruption across the UK with several yellow weather warnings in place.
The Met Office forecasts “unseasonable” conditions – with gusts of 40-50mph in west Wales, Devon and Cornwall, and parts of the Channel coast.
Motorists have been urged to avoid unnecessary travel because of poor driving conditions.
The rain warning covers Whaley Bridge, where residents were recently evacuated after a dam above the town was damaged.
Derbyshire Police said the residents, who were allowed to move home on Wednesday, would be “the first to know”. if the water in the Toddbrook Reservoir reached a “level of concern”.
Weekend thunderstorms could bring flooding, closed roads and power cuts.
A band of heavy rain followed by heavy showers or thunderstorms has been forecast for most of the UK, triggering a rain warning for the whole of Friday.
The Met Office says 10-15mm of rain is widely expected, with as much as 30mm expected to fall in a few hours in some places.
The wind warning covering parts of Wales and south-west and southern England lasts from 15:00 BST until midnight. A similar warning affects most of England and Wales for the whole of Saturday.
The warning of thunderstorms will last through Saturday into Sunday morning, covering Northern Ireland, most of Scotland and northern parts of England.
Neil Armstrong, chief meteorologist at the Met Office, said: “This low-pressure system will bring challenging conditions, including unseasonably strong winds and heavy rain, from the west.”
“Summer storms – compared with those in autumn and winter – always have the potential to create additional impacts because more people are likely to be outdoors, especially by the coast,” he added.
Mr Armstrong said trees in full leaf – as they were in summer – were also more vulnerable to being felled by strong winds.
Richard Leonard, head of road safety at Highways England, urged drivers to check conditions before they travelled and consider whether their journey was necessary.
“In high winds, there’s a particular risk to lorries, caravans and motorbikes so we’d advise drivers of these vehicles to slow down and avoid using exposed sections of road if possible,” he said.
“There is some fairly heavy rain and thunderstorms from Bristol, up through Wales and into Northern Ireland,” a spokesman for the Met Office said.
“That will transfer eastwards over the next few hours, causing poor driving conditions in places.”
The RNLI has warned people visiting the coast to beware of large waves and storms.
Summer events disrupted
The predicted 60mph winds prompted organisers of the Boardmasters music festival in Newquay to call the event off – just hours before its doors were due to open on Wednesday.
Houghton, a dance music festival in Norfolk, was also cancelled just hours before it was due to start, its “devastated” organisers announced on Facebook.
The Bristol International Balloon Fiesta has been scaled back, while the National Eisteddfod music festival in north Wales said it had “contingency plans” in place.
St Annes International Kite Festival in Lancashire has been rearranged for September because of the severe weather, Fylde Council said.
Rail passengers across Scotland faced train delays for almost 24 hours on Thursday after a tunnel flooded following 50mm of rain on Wednesday.