Scientists have been fascinated by hailstone formation for decades, specifically how these icy spheres develop inside storm clouds. Hail occurs when raindrops are swept into the upper, colder ...

Supercooled water freezes at different rates, depending on the temperature of the hailstone surface, leaving layers of clear or cloudy ice as the hailstone moves around inside a thunderstorm.

Since this process is relatively slow (slower than the dry growth process) it results in a layer of clear ice ... The largest officially recognized hailstone on record to have been "captured ...

NARRATION: It takes very special conditions to create a hailstone. You need summer thermals ... where they collect more water, with new layers freezing on in a separate shell.