A heavy thunderstorm struck Villa Carlos Paz, Argentina, in February 2018 with gigantic hailstones, which scientists described as gargantuan. It was the size of a football.
The hailstorm lasted for about 30 minutes. Diego Concha, director of Civil Defense for Córdoba, said that some hailstones were as large as tennis balls, damaging many trees and houses.
Residents posted on social media pictures and videos of the massive hailstorm. One hailstone stood out measuring 17 centimeters (between 7.4 and 9.3 inches) and researchers believed it could set a new world record.
Granizo en Villa Carlos Paz @todonoticias pic.twitter.com/RJakJjW8sl — Leonardo Orozco (@LeoOrozco3105) February 8, 2018
A volleyball-size hailstone that fell on Vivian, South Dakota in 2010 holds the current record at 8 inches. It also weighs 1 pound and 15 ounces, which is the heaviest recorded for hail.
Matthew Kumjian, associate professor in the Department of Meteorology and Atmosphere Science at Penn State said that it is extremely unexpected from hail to have those dimensions, and the thought of something as large is incredible.
A new classificaiton: gargantuan hail
These circumstances forced scientists to propose a new name for hailstones bigger than six inches. They should be categorized as gargantuan. He also said providing greater knowledge of these rare events could help lead to a "better understanding of the dangerous storms".
Kumjian said hail bigger than a quarter can leave a dent on a car while a 6-inch one can actually go through roofs.
"We'd like to help mitigate the impacts on life and property, to help anticipate these kinds of events," Kumjian told PennState News.
According to the National Oceanic and Atmospheric Administration's (NOAA) National Severe Storms Laboratory (NSSL), hail is formed when raindrops are pushed by thunderstorm upward into "extremely cold areas of the atmosphere and freeze". It grows by bumping into liquid water that freezes onto the hailstone.
Meanwhile, hailstorm happens when the updraft can no longer carry support the weight of the new hailstones, which fall at up to 100 mph. They can damage aircraft, homes, and cars. These can also be deadly to animals and humans.
The need for more photogrammetric investigation
After a year, researchers went to the site to investigate. They interviewed witnesses, visited the locations where the damage occurred, collected photogrammetric data, and analyzed radar observations.
They took measurements from photographs--called photogrammetry--and video evidence, and one hailstone stood out that scientists thought may snatch a world record.
Later, they reported the results of the research, which was funded by the National Science Foundation and the Insurance Institute for Business and Home Safety, in the Bulletin of the American Meteorological Society.
"Such a well-observed case is an important step forward in understanding environments and storms that produce gargantuan hail, and ultimately how to anticipate and detect such extreme events," Kumjian said.
Rachel Gutierrez, a graduate student at Penn State and co-author of the paper, said there is not much data from storms outside the U.S. "Having this shows us these crazy, high-impact events can happen all over the world," she said.
Gutierrez also said that gargantuan hail events may be more common, but volunteers who are willing to report the event and provide accurate measurements are needed to get a better grasp of this occurrence.
