Graupel

Graupel, or Snow Pellets

The result of ice crystals and supercooled water droplets frozen together is referred to as graupel. This form of frozen precipitation is also known as snow pellets or soft hail. While harmless compared to the damage of a hailstorm, the static buildup may sometimes result in lightning. The sign and magnitude of charge in these thunderstorms depends on a variety of factors including ice crystal size, graupel velocity, and temperature.