CROWDS heading to the second day of the Trnsmt music festival could face thunderstorms as temperatures rise and the Met Office issue a warning.

A yellow weather warning has been put in place for the majority of the UK between 9am and midnight on Saturday.

As of 11am on Saturday, the Met Office forecast raises the chance of thunderstorms between 5pm and 7pm and again at 10pm – around the time headliner Sam Fender will be set to take the stage.

The festival has warned fans to be prepared for all weathers. 

Across the UK, temperatures were initially predicted to reach 33C on Saturday – the hottest temperature this year – but the latest forecast from the Met Office suggested it will reach 30C or 31C in East Anglia.

However, a thunderstorm warning is now in place for Saturday until midnight from London to north-west Scotland.

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Both Wimbledon and the Ashes Test match at Headingley in Leeds have already been disrupted by the weather.

Simon Partridge, Met Office forecaster, said: “On Saturday we’ve got very warm, very muggy, very humid air across the UK, we now have this cold front which is just starting to move into the warm muggy air.

“Thunderstorms started from about 7am, there’s been very heavy downpours already, we’re expecting it to continue throughout the afternoon, the main focus will be the north of the Midlands.

“Heavy downpours are possible, particularly if you get two or three together in the space of a couple of hours.

“There is the potential for up to 50mm of rain in a few spots, most likely heavy downpours and difficult driving conditions.

“We will be keeping an eye on it in case there’s a need to upgrade the warning this afternoon to amber.”