A hailstone that fell from a severe thunderstorm in South Dakota has been officially declared the largest ever recorded in the United States, in terms of both diameter and weight, according to the NOAA National Climate Extremes Committee.
The stone was 8.0 inches in diameter, 18.62 inches in circumference, and weighed one pound, 15 ounces.
This is just short of the size of a soccer ball.
The record-breaking hailstone fell in Vivian, South Dakota. It was found by Les Scott, who immediately took action to preserve it. "Mr. Scott told me the area was littered with large hailstones and the largest had a greater diameter when he first found it," said David Hintz, warning coordination meteorologist at the Aberdeen weather forecast office. "He immediately stored it and several others in his freezer, but a power outage caused some melting."
The weather office in Aberdeen, South Dakota notified regional weather authorities, who then requested activation of the National Climate Extremes Committee to evaluate the massive hailstone. Official measurements were submitted to the committee of three, who then certified that the hailstone was a record-breaker.
The previous record-holding hailstone in the weight category fell in Coffeyville, Kansas in 1970, and weighed 1.67 pounds. The previous record-holding hailstone in the diameter category fell in Aurora, Nebraska. It measured 7 inches across. This stone - at 18.75 inches - still holds the hailstone record for circumference.