What kind of structure do hailstones often exhibit?

Hailstones typically exhibit concentric layers of opaque ice. This characteristic is a result of the hail formation process, which involves strong updrafts in thunderstorms that carry water droplets above the freezing level. As these droplets are lifted repeatedly, they freeze and accumulate layers upon layers of ice as they are cycled through the updrafts, allowing new water to expose them to freezing conditions. This layering effect leads to the layered structure observed in hailstones, often resulting in a multi-faceted appearance of opaque ice.

The presence of these layers is important for distinguishing hail from other types of precipitation and is significant in understanding the dynamics of severe thunderstorms that produce hail. Each layer represents a cycle of freezing and melting, indicating the hailstone's journey within the storm’s updrafts.