The potential for severe weather poses a significant disruption to the Lollapalooza festival, impacting hundreds of thousands of attendees who travel to Chicago for the event. Heavy rainfall and flash flooding can lead to safety concerns, including hazardous ground conditions, reduced visibility, and potential infrastructure damage. High winds also present risks for stage setups and attendee safety. The unpredictable nature of thunderstorms can necessitate stage cancellations or delays, frustrating festival-goers and artists alike. For those attending, understanding these weather patterns is crucial for planning travel, ensuring personal safety, and making informed decisions about attending specific performances.