The Chandelier singer was due to hit the stage at the site in Chelmsford, Essex when it was announced that due to the high winds and rain, Sia may not be able to put on her theatrical production.
"The live show is not possible because of the wind," the announcer said. "We are doing everything in our power to provide you with a show despite Mother Nature."
They also apologised on Sia's behalf and said she promised to sing "extra hard" for the audience when she made it onto the stage.
After a 15-minute delay, the weather calmed down and the Australian singer was able to begin, and similar to previous shows, she kept to the back of the stage, hid most of her face behind a large wig and didn't speak until the very end, when she said "Thank you" repeatedly.
Unlike most performers, Sia didn't use the screens at the side of the stage to show her live performance and instead they played pre-recorded material and most of the movements were mirrored by dancers on the stage, leading many audience members to believe famous faces such as Kristen Wiig and Paul Dano were at the festival too.
Sia was recently hit with a class action lawsuit from fans in Tel Aviv, Israel who were upset with her show and were suing for all audience members to receive their ticket money back. They claimed the show was "impersonal" and too short, according to reports.
She seemed to respond to the legal action on Twitter on Friday (19Aug16), by writing, "This euro tour has been amazing. Thank you all for singing at the top of your lungs and for welcoming me with such open hearts... I put everything I have into my show - it's abstract for sure, but I'm singing my heart out live and every moment is purely intentional."
She is due to perform again at the festival other site in Staffordshire, England on Sunday (21Aug16).