Usually roughly spherical and sometimes pellet shaped, these objects form in cumulonimbus clouds with strong updrafts that form the front of a moving thunderstorm.
This phenomenon occurs mostly in the summer, especially at high altitudes. Its effects vary in size from about five millimeters up to one hundred seventy millimeters in diameter and are either aggre- gates of smaller objects or concentric layers of frozen condensate around a central nucleation site. Usually roughly spherical and sometimes pellet shaped, these objects form in cumulonimbus clouds with strong updrafts that form the front of a moving thunderstorm. If large enough, they can damage cars and even cause head trauma. Identify this type of ice precipitation.
This phenomenon occurs mostly in the summer, especially at high altitudes.
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