The size of the hailstones is essentially linked to the power of the storms, and the intensity of the ascending and descending currents. Hail is indeed formed in these columns of air. The water, carried by the winds in the form of thousands of micro-droplets, freezes at altitude. The longer it stays in the clouds – or rises there via the updrafts – the more it will form a large mass before falling. Therefore, the more violent the storm and generates strong winds, the higher the risk of having massive hail showers.
“Such stormy episodes are not unusual in this region at this time, even if the size of these hailstones does indeed seem exceptional to say the least.“, reframes Pascal Mormal, meteorologist at the IRM. “With the heat of the past few days coupled with humidity and air mass conflict, there was only a small fuse left to light.“According to the specialist, it is not easy to link the size of these hailstones to global warming, but it is however proven that extreme events are likely to multiply.
Moreover, he wishes to qualify these data. “We must also take into account that today we have many more tools than at the time to measure and document the size of these hailstones, but nothing tells us that such hailstones have not already existed.“.
This new European “record” is close to the world record currently held by a 20.3 cm hailstone measured on July 23, 2010 in Vivian, South Dakota in the United States… But it would not be surprising if it were soon beaten again.
