How do ice crystals grow in clouds?

Question

Explain how ice crystals grow in a cloud. Under what conditions will the ice crystals fall as snow? Under what conditions will the ice crystals form hail?

Answer 1

Ice crystal grow in clouds like frost forms on the ground.  water vapor sublimates directly into a tiny crystal, and the process in turn helps more vapor to crystallize.  If the crystals grow large enough they will fall as snow.

Ice crystals do not turn into hail.  Hail is water drops that are lifted above the freezing layer and subsequently frozen.  The ice ball then typically cycles below then back above the freezing level, being coated with more water which freezes.  Eventually the hailstone becomes too heavy to be held aloft, and it falls to the ground.

Answer 2

Ice crystals form as a result of continuous condensation of "rain droplets." The result of hail or snow is based on what type of storm is available, how many times the crystals condensate to form layers in the ice, and the amount of weight is on the crystal which can either cause snow or hail. Obviously, hail would result of a heavy amounts of condensated "water droplets." Snow would be light and thus occur more quickly than hail.