This Terrifying Hailstone May Have Set a New World Record

CC BY 2.0. A gargantuan hailstone that fell in Argentina may have set a world record, according to researchers. (Photo: Victoria Druetta)

A supercell thunderstorm in Argentina delivered shockingly huge hailstones to the heavily populated city of Villa Carlos Paz.

Meet "Victoria's hailstone," pictured above. The massive hunk of ice hurtled down from the sky in a famous hailstorm that hit the city of Villa Carlos Paz, Argentina in 2018.

Victoria Druetta and her family were watching the storm from a window when the monster hailstone landed within view, breaking as it hit the ground. “It was really impressive, we were all in shock,” Druetta said. Her brother encouraged her to go out and get it – so she (smartly) put on a motorcycle helmet and did so. She was unable to find that piece that broke off, but she got the main stone and did what one does when they find a hailstone that weighs almost a pound and is the width of a soccer ball – she took photos for social media and stuck it in the freezer.

Now scientists from Penn State reviewing Victoria's treasure, and others collected from the same storm, have suggested that it is time for a new category to describe hailstones of such magnitude: "gargantuan hail."

For the research, the scientists followed up on the accounts the following year. They conducted interviews with witnesses, documented sites that saw damage, and used photogrammetric data and radar observations.

The team says that Victoria's hailstone likely measured between 7.4 and 9.3 inches across, which they note, "is close to or exceeds the world record for maximum dimension." It weighed 442 grams; just under one pound. The current record is held by a hailstone that measured 8 inches across that plummeted to the ground in Vivian, South Dakota.

"It's incredible," said Matthew Kumjian, associate professor in the Department of Meteorology and Atmosphere Science at Penn State. "This is the extreme upper end of what you'd expect from hail."

For the new classification recommendation, the researchers say that hailstones of 6 inches or more would qualify. They also note the importance of more awareness of these kinds of rare events, which could help us better understand dangerous storms.

"Anything larger than about a quarter in size can start putting dents into your car," Kumjian said. "In some rare cases, 6-inch hail has actually gone through roofs and multiple floors in houses. We'd like to help mitigate the impacts on life and property, to help anticipate these kinds of events."

The research was published in the Bulletin of the American Meteorological Society.