This article is more than 1 year old

This article is more than 1 year old

Unseasonal weather, possibly driven by climate change, has caused widespread disruption and prompted the Met Office to issue yellow weather warnings across much of the UK.

Festivals have been cancelled and floods are expected as the extreme weather is forecast to continue over the weekend.

“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.”

Organisers cancelled the annual Race Across Torbay on Sunday as weather warnings for Devon and Cornwall were issued. The Houghton music festival in Norfolk and Boardmasters in Newquay were also cancelled this week.

Warnings are expected on Saturday for all of Wales and most of England and thunderstorms predicted across Scotland and Northern Ireland, where torrential showers could cause flooding and road closures.

The meteorologist Bonnie Diamond said: “We will certainly see an impact in terms of localised flooding, difficult driving conditions and transport delays.”

Diamond also said that Antrim in Northern Ireland had 39mm of rainfall between 9pm on Thursday and 9am on Friday, the largest amount in the 12-hour period. The country’s August average is 97.4mm.

On Sunday the bad weather is expected to concentrate over northern England, Scotland and Northern Ireland, with thunderstorms and 60mph winds in places.

Neil Armstrong, the Met Office’s chief meteorologist, said: “This low-pressure system will bring challenging conditions, including unseasonably strong winds and heavy rain, from the west during Friday and Saturday.

“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.

“Additionally with trees in full leaf they are more vulnerable to being brought down by strong winds.”

Whaley Bridge in Derbyshire is under a weather alert after more than 1,000 residents who were evacuated returned to their homes this week. They had to leave when the Toddbrook reservoir dam threatened to give way during previous bad weather.

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Derbyshire police assured residents that if the reservoir reached a level of concern, those living in the evacuation zone would be the first to know.

Highways England urged people to travel by car only if necessary over the weekend. Conditions are expected to calm on Monday, when no warnings are expected.

Richard Leonard, the head of road safety at Highways England, said: “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.”

Showers have disrupted the British summer over the past few days. Rail passengers experienced delays and cancellations in and out of Edinburgh after flooding in the Winchburgh tunnel in West Lothian.