hailstorm

Precipitation of hail. In hailstorms, the quantity, size, and shape of the hailstones are highly variable. In the most intense ones, a layer several decimeters thick can form on the ground, and it is also common for large-caliber hailstones to fall. Those hailstones are formed by conglomerates of several hail grains, which previously collided with one another violently within the storm cloud, fusing together and giving rise to irregular blocks of ice.