For the summer solstice on Wednesday, Carnegie Science Center visitors were greeted with all the hallmarks of a perfect Pittsburgh day: temperatures in the 70s, bright blue skies, and snowballs to fling into the Ohio River. 

The only snowball-throwing event where you might want to bring sunscreen, Snowball Day at the science center is a long-running tradition. Since 2006, the museum has invited people near and far to celebrate the beginning of the season by remembering the past winter. In previous years, most attendees had saved snowballs from the winter in freezers, hauling them to the North Shore in insulated bags and coolers. 

But this year, Pittsburgh had an unusually mild winter — the eighth warmest recorded so far. Thanks to climate change impacts, Pittsburgh saw the least amount of snow on record during February, leaving many unable to make their own snowballs to bring. 

As Brad Peroney, the science center’s director of team and community engagement, explained, organizing the event was a little more complicated than usual. By February, the team realized that people might not get the opportunity to make their own snowballs. In anticipation of the typical 1,000 or so attendees, staff members prepared with lots of ice, a commercial ice shaver, and a backup, just in case, to provide unlimited snowballs for all who ventured to the museum. 

Akshay Lath, 14, from Pittsburgh, was ready with a cooler of his own snowballs, which he’s been storing for not months but years. “Before COVID, it was really cold, I think it was minus 20 degrees [for a] whole week. So we went outside, we got some snowballs, we put them in the freezer and waited for Snowball Day. And then it never came.”

Carnegie Science Center crew members demonstrate the big snowball slingshot on June 21, 2023. (Delaney Park/Pittsburgh Union Progress)

While Snowball Day returned in the meantime, this was the first year Akshay was able to make the event and finally launch the snowballs he had stored three years before in a little freezer in his mother’s South Side office. This wasn’t his first snowball day, though. He still remembers attending once when he was only 4 or 5.

According to Peroney, many families look forward to Snowball Day every year, and it’s an educational event as well as a celebratory one. “Not only is it just fun to launch snowballs in the beginning of summer, but there’s also a lot that we can learn about projectile motion,” he said. “And people can experiment with ways they can get that snowball to the science center without it melting, so that’s some fun family science that they can do at home.”

Kids and adults alike had a few different options for throwing the snowballs. Some chose to toss them by first loading them into multicolored plastic tools that you could load up and throw with, while others used their bare hands. For the mighty, there was another option: a massive slingshot, which took three people to operate and allowed visitors to hurl snowballs far and wide into the middle of the river. 

For Barrett Owens and his family, who were in town from Harrisburg, Snowball Day was the perfect fit for the last day of their summer trip, which included classic Pittsburgh destinations such as the Incline and Primanti Bros. He hadn’t heard about the tradition before but was glad he opted to bring his sons, Adam and Dylan, to the museum. The boys added that they especially enjoyed the giant slingshot, which Adam said was “pretty fun.”

Alina Riley from the North Hills also took her two toddler sons, Wes and Clive, to participate in the first-day-of-summer festivities. She was surprised, but excited, by the idea: “I never thought that it would be possible to do this!” 

In between walking her boys back and forth from the snowball-making station to the river, Riley joked, “It’s good that you have to work for the snowball. You gotta climb up all of those stairs, you know? So you will appreciate every single one you make.”

The whole Carnegie Science Center has gotten in on the theme, Peroney added. There’s a film showing in 2D and 3D called “Arctic: Our Frozen Planet,” as well as “Freeze!”: a live show exploring the effects of liquid nitrogen.

Just as Snowball Day marked the beginning of summer, the museum has something in store to commemorate the end: MessFest will give visitors the opportunity to make slime, squirt gun art, and more in late August. 

Keara Harrington gets ready to launch a snowball on June 21, 2023. (Delaney Parks/Pittsburgh Union Progress)

Delaney, a rising senior at the University of Pennsylvania, is a Union Progress summer intern. Reach her at

Delaney Parks

Delaney, a rising senior at the University of Pennsylvania, is a Union Progress summer intern. Reach her at