New York's Electric Zoo festival has been cut short due to storms.
Music fans were evacuated from the the Randall's Island event on Sunday (31Aug14) as extreme weather conditions threatened to cause havoc at the site.
Organisers have apologised to festival-goers, stating, "Ultimately our main concern is for the safety and security of all attendees, artists and staff."
Kaskade and Skrillex were all scheduled to headline the three-day event's final night when it was cancelled.
The second day of Jay Z's Made in America festival in Philadelphia, Pennsylvania was also affected by severe weather conditions.
Fans were asked to leave the site and find cover in "protected areas" late on Sunday afternoon.
A statement posted on the festival's website read: "Festival Alert - Severe Weather In Philadelphia. All Persons Should Move Quickly And Calmly To The Nearest Exit And Proceed To Your Vehicles And Protected Areas Outside Of The Festival Site. Please Seek Shelter For Your Safety.
"Please Retain Your Tickets For Re-Entry To The Show. We Will Open Gates Back Up Once All Is Clear. Please Pay Attention To Social Media And Festival Sites For Re-Entry To The Site.
Thank You For Your Cooperation."