When frozen rain moves up and down within an anvil cloud forms what?

When frozen rain moves up and down within an anvil cloud, it can lead to the formation of hail. The repeated cycling of ice particles through the cloud allows them to accumulate layers of supercooled water, which freeze upon contact. Once they become too heavy to be supported by the updrafts, they fall to the ground as hailstones. This process is typical in severe thunderstorms with strong updrafts.