(Radio Iowa) – As many as 100,000 people are expected to attend tonight’s Yankee Doodle Pops concert on the West Terrace of the Iowa State Capitol grounds. The 30th annual event highlights the Des Moines Symphony, where spokeswoman Calla Whipp says it’s Iowa’s largest single-day concert event.

“We have live concert starting at 6:30 p.m. with two jazz groups, and then the orchestra takes the stage around 8:30 p.m.,” Whipp says. “It’s patriotic favorites for about an hour and a half and it ends with fireworks. They play the ‘1812 Overture’ and we have cannons, which is kind of fun and unique.”

The winner of the symphony’s annual “Oh Say, Can You Sing?” contest will open tonight’s show with “The Star-Spangled Banner,” and Whipp says one of the evening’s featured vocalists is Hugh Panaro. “He is a Broadway star. He’s been in 2,000-plus showings of ‘The Phantom of the Opera’ as the Phantom and then also as Raul, so he toured with the Phantom,” Whipp says, “and then Carrie Ellen Giunta will be joining him for a couple of duets. She’s actually local, too, which is kind of fun.”

The Des Moines weather forecast calls for a 30-percent chance of showers tonight, so she’s hoping the clouds cooperate — or at least wait until after the show, as the concert always draws an enormous audience.

Des Moines Symphony photo

“There is a very large crowd that comes,” Whipp says. “We have people that start staking their claim on the grounds as early as eight o’clock in the morning, which is kind of crazy, but there’s always plenty of space on the lawn. It’s big. You can hear the music as there are speakers everywhere.”

Tonight’s concert is free to attend and will be broadcast live both on Iowa PBS and Iowa Public Radio.