The UK Meteorological Office warned that thunderstorms, wind and hail are forecast to sweep across the UK this weekend and could cause flash flooding.

It said the warm and humid air this week had caused the storms to develop.

ONE yellow weather warning for England, Wales and Northern Ireland will be on Sunday, with a weekend of unsettled weather impending for some.

BBC Weather’s Matt Taylor says some of the worst storms can produce the equivalent of a month’s worth of rain in just a few hours.

But the hot weather will continue, with temperatures reaching 29 degrees Celsius (84 degrees Fahrenheit) in some areas.

There is a chance that homes could flood quickly as some areas could see up to 80mm of rain in an hour on Sunday, the Meteorological Office said, and storms could also lead to power cut.

BBC Weather meteorologist Matt Taylor said on Saturday that the western half of Northern Ireland was most likely to experience thunderstorms, with a yellow warning in place for the area between 14:00 and 21:00 BST.

On Sunday, warnings were in place across Wales, most of England and western Northern Ireland from noon until late evening.

Mr Taylor said: “There is a high chance of thunderstorms developing across the UK and Ireland through the weekend, as humidity continues to rise…

“The storms come with frequent risk of lightning, hail, strong winds and some flooding resulting in disruption.”

However, he said that not everyone will see the storm, with conditions “very variable over short distances and many areas still dry”.

He added late on Sunday and into the night, thunder showers could affect more of northern and eastern England, as well as eastern Scotland.

Storm forecast follows a week of high temperatures where many parts of the UK officially experience a heatwave.

The heat wave has left some people with severe hay fever and worsening asthma attacks.

People have been complaining on social media that their hay fever symptoms are worse than usual this year.

Grahame Madge, a spokesman for the Met Office, said it was the result of hot and dry weather over the past few weeks.

“Pollen season is definitely with us,” he said. “The fact that we have very arid conditions means that grasses can release pollen in large volumes into the air column.”

Heatwaves are becoming more likely and more extreme due to human-caused climate change.

The world has warmed by about 1.2 degrees Celsius since the industrial era began, and temperatures are expected to continue to rise.

Despite the storms, the heat continued. The highest temperature of the year so far was at Chertsey Water Works in Surrey on Saturday, where a peak of 32.2C was recorded.

Up to 4,000 customers have been without water or have suffered from low pressure since Monday due to supply problems.