A Northern Illinois University meteorologist joined a research team this week to measure a likely record-breaking hailstone from a severe storm in Kankakee County on March 10.

Victor Gensini and scientists from the Insurance Institute for Business and Home Safety examined the specimen and documented several additional large hailstones collected by area residents, according to an NIU news release.

Among them was one stone that measured 6.6 inches and weighed 19.65 ounces – significantly larger than the current state record of 4.75 inches set in 2015.

“This is about the size of a mini Nerf football – quite remarkable,” Gensini said in the release.

The Insurance Institute for Business and Home Safety, an independent nonprofit research organization supported by the insurance industry, partners with scientists to study hail both in the field and in laboratory settings.

Gensini, a leading expert in severe weather and hailstorms, has spent more than a decade researching the formation, frequency and impacts of hail. A professor and a certified consulting meteorologist in NIU’s Department of Earth, Atmosphere and Environment in DeKalb, Gensini joined an $11 million nationwide hailstorm study in spring 2025, calling it “a once-in-a-career” project.

The stone hasn’t yet been verified. But once done, it could become the largest recorded hailstone in Illinois, and potentially the largest observed in the state since record-keeping began in the mid-20th century.

The process to officially confirm such a specimen requires more review through an established verification process, according to NIU.

The hailstones were produced by a powerful supercell thunderstorm that swept through northern Illinois and northwest Indiana the night of March 10. A deadly tornado in Kankakee County swept through the village of Aroma Park, killing one and causing significant property damage.

Shaw Local reported that residents saw significant hail damage to property, cars and other areas.

While tornadoes often draw the most attention, hail remains one of the costliest thunderstorm hazards in the country, causing billions of dollars in damage each year to homes, vehicles and businesses.

At NIU, researchers conducted detailed measures and 3D scans of the hailstones as part of the verification process. The stones were preserved by local families, including one from Kankakee County, which allowed scientists to study them before they melted.

Events like the March 10 storm provide critical opportunities for researchers to better understand how and why extreme hail forms and how communities can better prepare for it.

Research suggests severe storms will become more common

Genisini is the director of NIU’s Center for Interdisciplinary Research on Convective Storms. He’s led and contributed to major national research efforts, including large-scale field campaigns collecting thousands of hailstone samples, according to NIU.

Genisini’s also part of ICECHIP, the largest hail study ever, which brought together more than 100 scientists from across the U.S. to document and analyze storms.

The research aims to improve forecasting, better understand storm behavior and reduce costly impacts of severe weather.

So far, the research suggests that large hail events may become more common in the future. That’s because changing atmospheric conditions will likely contribute to stronger storms capable of producing larger hailstones, according to NIU.

“We are dedicated to continued monitoring of these extreme hail events due to their significant economic impact,” Gensini said.