Despite a two-and-a-half-hour delay and the evacuation of Grant Park in Chicago due to a severe thunderstorm, Lollapalooza bounced back with a revised schedule for Saturday (August 4) to keep festival goers happy. Lolla vets Red Hot Chili Peppers helped keep the vibe alive with their headlining set on the Red Bull Soundstage.

Over 60,000 people were forced to leave the festival grounds and seek shelter in designated emergency areas after torrential downpour and high winds threatened to shut down the entire operation. Luckily, Chicago city officials and Lollapalooza organizers were able to extend the night curfew and reopen the gates at 6PM. Some artists had to be cut from the schedule or have their set shortened, with Alabama Shakes, Chairlift, B.o.B. and Temper Trap being included in the former.

With most of Grant Park transformed into a massive mud bath, the Red Hot Chili Peppers made sure the people who returned to Lolla had one hell of a time. The rock and roll hall of famers played a majority of their classic tunes, including a punked out "Can't Stop", the always-great-to-sing-while-drunk "Under The Bridge", "Around The World" and more. It was only appropriate that they performed "The Adventures of Rain Dance Maggie," taken from their 2011 album I'm With You, after Mother Nature punished Chicago for a few hours.

Most recent guitarist Josh Klinghoffer was the same shot-in-the-arm presence for the band that he was at the Chili Peppers' Grand Rapids show at Van Andel Arena back in May. Frontman Anthony Kiedes, bassist Flea and drummer Chad Smith were no slouches either, wildly moving around to the beat of their trademark mix of rock, punk and funk. The band played a two-song encore that composed of their new single, "Brendan's Death Song," and the Blood Sugar Sex Magik classic, "Give It Away." Watch the Red Hot Chili Peppers perform "Around The World" during their Lollapalooza 2012 set below.

Other highlights from Saturday included EDM artist Calvin Harris at Perry's Stage, who fistpumped the crowd into a mud-soaked frenzy. We actually witnessed a couple having a fight during the DJ's set, totally oblivious to the fun people were having around them. They definitely weren't following the theme of the Harris-produced Rihanna track, "We Found Love," or his most recent hit "Feel So Close." Unlikely hit makers fun. were able to stay on the Lolla schedule and performed on the Google Play stage. R&B singer Frank Ocean headlined the same stage later in the night, crooning to the crowd who came to watch him. Nine months from now, newborns can thank Ocean for inspiring their parents to conceive them.

Watch Red Hot Chili Peppers Perform "Around The World" at Lollapalooza 2012

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