Doppler view of the storm that descended on Chicago Saturday during the Pitchfork Music Festival. Credit: Courtesy Accuweather.com

Severe weather prompted an evacuation of Union Park on Saturday afternoon during the 2015 Pitchfork Music Festival.

At around 3:40 PM, a voice came over the PA announcing that the thousands of attendees present would have to leave the park in 20 minutes. The rain-soaked crowd responded with boos as Ex Hex was forced to cut short its set after less than 20 minutes. 

With the storm clearing, the park is expected to reopen at 4:20, which has prompted the expected stream of pot-related humor on Twitter.