Friday Fireworks Nights at Principal Park are back!! When the Iowa Cubs play at home on a Friday night, fireworks will reign over downtown Des Moines. Late Friday night, I was watching TV and packing for Mother's Day weekend when I heard a loud boom and saw the fireworks over Principal Park. What a great sight it was!!!! Not only were the fireworks cool, but so was the crowd noise, a sure sign that life is returning to downtown Des Moines and beyond! The next fireworks nights at Principal Park following the Iowa Cubs games are: May 21, May 28, June 11, June 25, July 9, July 30, August 6, August 27, and September 10.