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hail
HAIL
Hail is a product of thunderstorms
or intense showers. It is generally white and translucent, consisting of liquid
or snow particles encased with layers of ice. It is formed in the updraft of
a storm or shower; where the rising, warm moist air feeds into a building cloud.
The particles are carried to below-freezing levels where they freeze into small
ice fragments. As they drop to the surface, they can be picked up again by other
up-surging air current. This process of transporting the fragments back and
forth between freezing and nonfreezing layers of air result in the onion-like
layers of ice on the original piece. When they finally becoming heavy enough
to overcome the force of the vertical air current, they fall to the ground as
hailstones.
Hail is more of a common occurrence in the Great Plain and the Midwest during
the spring and summer months. Strong to severe thunderstorms develop intense
updrafts which are able to keep hail aloft through much of the storm's lifetime.
When it does fall, the hailstones can range from pea size to golfball and baseball
size. When the hail reaches 3/4" or larger, the thunderstorm is considered
severe and a Severe Thunderstorm Warning is issued. Large hail can do plenty
of damage to automobiles, windows, roofs, crops and animals. The largest hailstone
reported in the US was 5 1/2" in diameter and weighted 1 1/2 pounds; it
occurred in Potter, Nebraska in 1928.
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