This is one of the largest hailstones ever observed in the United States. The stone fell on June 22, 2003 in Aurora, Nebraska.
Click on image for full size
Courtesy of University Corporation for Atmospheric Research


Hail is made in a cumulonimbus cloud where ice is tossed around by the wind. The ice crystals bump into each other and stick together making larger and larger pieces of ice. Very cold water droplets in a cloud freeze onto hailstones. When these pieces become too heavy, they fall to the ground.

Most hailstones are about the size of peas. The heaviest one in the United States was the size of a cantaloupe and fell on Kansas in 1970. Large hailstones can break windows and dent cars. A farmerís crops can be destroyed from hail in minutes. Hail is transparent or partially opaque in color.

Hailstones do not have a perfectly round shape because the warmer temperatures below a cloud cause some of the ice to melt. Hail can fall during violent thunderstorms in the summer. Even though the summer air is warm, hail can make its way to the ground as ice without melting completely if it is large enough.

Last modified July 28, 2008 by Vanessa Pearce.

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