Heavy Storms Shake Up Lollapalooza

Fans are evacuated from Grant park due to an approaching storm during 2012 Lollapalooza at Grant Park on August 4, 2012 in Chicago, Illinois.

Organizers Briefly Shut Down Festival; Alabama Shakes, B.o.B. + Others Lose Their Set Times

Lollapalooza was briefly shut down on Saturday afternoon when heavy storms rolled into Chicago.

At around 3:30 p.m. CT, festival organizers announced they would suspend the massive festival in light of National Weather Service reports of severe thunderstorms. Attendees were urged to move to pre-determined evacuation zones.

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"Our first priority is always the safety of our fans, staff and artists," said Shelby Meade, communications director for C3 Presents, in a statement posted to the festival's website. "We regret having to suspend any show, but safety always comes first."

Afternoon sets from bands like fun. and The Weeknd were postponed and rescheduled for later in the evening. Buzz band Alabama Shakes was not so lucky, and lost their set altogether.

"Sorry Chicago, we were really pumped to play for you all but the storm had other plans," the group tweeted. "We will be back to make it up for you!"

During the storm, attendees were evacuated to three official locations, while many downtown Chicago hotels were flooded with guests and Lolla-goers alike. Around 4:45 pm, folk-rock group The Dunwells played an impromptu 2-song set at the Hilton's Normandie Lounge while they waited, in vain as it turned out, for a new time for their set at the BMI stage. Like Alabama Shakes, their set was nixed.

"Our Lollapalooza set has been cancelled due to a crazy-ass storm," they told fans on Twitter.

Sets by B.o.B., the Temper Trap and Paper Diamond were also canceled.

Also at the Hilton, Spoon lead singer Britt Daniel, also of Divine Fits, headed down to the lobby to "check out the chaos," as he told Billboard.

At approximately 6:50 p.m., the gates were re-opened, to the tune of the "Star Wars" theme. Updated times can be found here.