Weather can change very quickly in the Alps. Notably, towards late afternoon, heavy thunderstorms can appear out of nowhere. Just look at the example of July 9 in the Gantrisch region. Farmer Christoph Stucki sent the pictures and video from a storm with hailstones up to 3 inches thick. The cows were unprotected on the meadows and got abrasions on their bodies, one even had a black eye.