Image Place Holder right
Everyone
knows that it doesn't take a large hailstone to cause much damage. But
out of curiosity, how big can hailstones get?
While
most hailstones are the size of peas (about 0.25 in [0.63 cm] in diameter),
they sometimes grow larger than softballs. Large hailstones have been
responsible for destroying crops, breaking windows, and denting cars,
and have caused the deaths of many people and animals.
Hail
causes nearly one billion dollars (U.S.) in damage to property and crops
annually. The costliest United States hailstorm: Denver, Colorado, July
11, 1990. Total damage was 625 million dollars (U.S.). Hail falls when
it becomes heavy enough to overcome the strength of the updraft and is
pulled by gravity towards the earth. How it falls is dependent on what
is going on inside the thunderstorm. Hailstones bump into other raindrops
and other hailstones inside the thunderstorm, and this bumping slows down
their fall.
Drag
and friction also slow their fall, so it is a complicated question! If
the winds are strong enough, they can even blow hail so that it falls
at an angle. This would explain why the screens on one side of a house
can be shredded by hail and the rest are unharmed! Hail is a form of precipitation
that occurs when updrafts in thunderstorms carry raindrops upward into
extremely cold areas of the atmosphere where they freeze into ice.
The
National Climate Extremes Committee, which is responsible for validating
national records, formally accepted the measurements for the largest hailstone
ever to fall in the U.S.: seven inches in diameter (17.8 centimeters)
and a circumference of 18.75 inches (47.6 centimeters). The old record
for the largest hailstone had a diameter of 5.7 (14.5 centimeters) inches,
a circumference of 17.5 inches (44.5 centimeters), and was found in Coffeyville,
Kansas, on September 3, 1970. The previous longstanding record was believed
to be a hailstone which fell at Potter, Nebraska on July 6, 1928. It measured
around 7 inches (17.8 centimeters) in diameter and weighed about 1.5 pounds
(680 grams).
The
largest hailstones ever reported, weighing up to 7.5 pounds (3.4 grams),
fell in the state of Hyderabad, India, in 1939. However, scientists believe
that these huge hailstones may have been several stones that partially
melted and stuck together. On April 14, 1986, hailstones weighing 2.5
pounds (1 kilogram) each were reported to have fallen in the Gopalgang
district of Bangladesh.
Clearly
hailstones can become quite large given the right meteorological conditions.
All of which begs the question, with the current environmental changes
occuring...can we expect hailstones to get heavier and larger as the years
roll on?
|