With a diameter of up to 19 cm, hailstones in Europe are getting bigger and bigger

According to ESSL, which has a research and training center in Wiener Neustadt, 2023 will be the third record-breaking hail season in a row. In addition to the sheer number of reports, the number of days with large hailstones was also record-breaking. There were 229 days with large hail, 96 days with very large hail and 13 days with gigantic hail. The data runs until January 20, 2024. In total, there were 9,627 reports of hailstones larger than two centimeters last year. According to the international severe weather research institute ESSL (European Severe Storms Laboratory), 1,931 reports concerned very large hailstones (more than five centimeters) and 92 reports even mentioned gigantic hail larger than ten centimeters.

Not only were records broken again for the amounts of large and very large hail, but also for the maximum hail sizes. The largest photographed hailstone in Europe was recorded twice in Italy in just five days. On July 19 last year, a hailstone with a diameter of 16 centimeters was reported, and on July 24 one with a diameter of 19 centimeters.

The heaviest hailstone weighed 484 grams
In both cases, hail sizes were estimated using reference objects placed near the hailstones, ESSL pointed out. The heaviest officially weighed hailstone also fell on July 24, weighing 484 grams. The hailstone had a diameter of 13 centimeters. It is therefore assumed that the largest hailstones observed on July 19 or 24 were probably considerably heavier. In addition to Italy, other countries were also hit by huge hailstones. The largest hail had a diameter of 13.8 centimeters in Slovenia, 13 centimeters in diameter in Bulgaria and Croatia, eleven centimeters in France, Spain and Bosnia, and ten centimeters in diameter in Germany and Russia.

Long lasting hail storms
According to ESSL, the fact that the number of reports was so high could also be due to the fact that data collection has become more efficient. Private observers – citizens – made an important contribution to the reports. In addition, there were very long-lasting hailstorms in 2023, with large hailstones forming in many places. For comparison: in 2022 there were five hailstorms over a length of more than 200 kilometers. In 2023 there were thirteen such hailstorms, with one particularly long-lived supercell producing a hail strip of 686 kilometers long that even affected five countries.

The country with the most reports of large hail was France with 1,502 cases, closely followed by Italy with 1,468 reports. However, when it came to the most destructive hailstorms, Italy led the way with 596 reports of very large hailstorms and 67 reports of giant hailstorms, compared to 280 and 10 reports in France. The third country most affected by large hail was Germany with 1,270 reports, of which 142 were of very large hail.

The damage is enormous
The damage caused by this was enormous: at least 328 people were injured by the hail, the real number is probably much higher. Most of the injured (242) came from Italy. Hail also caused enormous economic damage. According to reinsurer München-RE, hailstorms in Italy cost billions of dollars, and the Gallagher-RE report puts the figure at three billion dollars (about 2.77 billion euros), with the total damage costs for the storms in Europe being around 2.77 billion dollars. twelve billion dollars.

Twice as many hailstorms in Austria
Pieter Groenemeijer of ESSL reported in the Ö1-Morgenjournal that the increase in heavy hailstorms was mainly observed in the Alpine region. For example, in Northern Italy the chance of hailstones with a diameter of five centimeters is 300 percent greater than before 1990. According to Groenemeijer, the number of hailstorms in Austria has doubled, and this is mainly observed in the south of the country. The increase in hailstorms in Europe is related to the warmer sea temperatures in the Mediterranean, Ö1 reported. Evaporation increases the amount of energy in the atmosphere, which rises in thunderclouds and causes strong updrafts. “The stronger the updraft, the larger the hail can be,” Groenemeijer says in Ö1.