It comes as the singer has been forced to cancel a number of gigs over the past month after suffering from laryngitis.
Now, she will have to finish off her US tour in August after disappointing fans last month by cancelling. Adele will then tour the UK in September with her record-breaking second album 21.
The free festival has already witnessed the likes of Paul Simon and Beady Eye take to the stage at Camden’s Roundhouse. A total of 61 artists will perform over the 31-night festival, including Arctic Monkeys, Foo Fighters, Rumer, Coldplay and Moby.
Tomorrow night will not be the first performance by Adele since getting a clean bill of health from her doctor. She played at Gay Pride last weekend.
Speaking of her illness to BBC Radio 1 DJ Chris Moyles, the British star said: “It’s basically a hole in your vocal cord but I sang through it so that’s why it popped. I’m better now it’s fine, I got the all-clear.”
She also told what it was like to perform Someone Like You at the Brit Awards, which saw her break down and cry.
“I’ve never actually been so scared in my life but it ended up being the most life changing night of my life,” she said.
“Everyone stood up. I’ve never been given a standing ovation by my peers and by the industry. It was amazing.”
Her performance has helped the song to sell more than one million copies – the first to do so this decade, it was reported today by the Official Charts Company. It is one of only 16 singles since 2000 to reach the milestone.
Hinting at her future plans, Adele told Moyles that she could be “doing something quite big next year”, but did not reveal any more details.
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