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Getting to Know: Extreme Weather
Have you ever witnessed a hurricane or a tornado? Hurricanes are enormous storms that sweep through entire regions, causing widespread destruction through heavy rains and winds. Tornadoes, on the other hand, are more localized, but they exhibit some of the fastest wind speeds on Earth. Some tornadoes actually have winds of up to 300 miles per hour! Extreme tornado winds can rip through just about anything in their path.
As you can see, these two types of storms are very
different, but they are alike in one important way.
Both types of weather are extremely powerful,
dangerous, and destructive. In fact, these events
are among the most awesome displays of raw
power that nature has to offer.
A tornado is one type of extreme
weather. Tornado wind speeds have been
recorded at up to 300 miles per hour.
What is extreme weather?
Hurricanes and tornadoes are among the different weather events that are known as extreme
weather. Can you think of other examples? Extreme weather also includes thunderstorms,
blizzards, ice storms, floods, and droughts.
Misconception 1: Does extreme weather always involve large amounts of
precipitation?
Extreme weather does not always have to involve precipitation. A drought, for example,
is defined by the extreme absence of precipitation rather than its abundance!
What are some of the different types of extreme weather, and how
do they form?
Some of the better known types of extreme weather include hurricanes, tornadoes,
and thunderstorms. Hurricanes are powerful tropical storms with winds moving at over
120 kilometers per hour. They begin as tropical storms, which are caused by low-pressure
air combined with warm water and high humidity. If tropical storms are large enough, they
will become hurricanes. Hurricanes have a distinct spiral shape caused by their high winds
and can be hundreds of miles wide. The hurricane’s eye is an area of relatively calm winds
at the center of the hurricane. The combination of high winds, precipitation, and flooding
associated with a hurricane can be incredibly destructive. Tornadoes are fast-moving funnels
of wind that often form during periods of warm weather when warm, moist air meets cold,
dry air. The warm air rises through the cold air and creates a spinning funnel of wind called
a supercell. A tornado forms when the supercell is drawn down and touches the ground.
Concept: Extreme Weather
Getting to Know
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Thunderstorms are strong rainstorms with heavy winds. Thunderstorms are generally
accompanied by lightning and thunder and sometimes can even include hail. Thunderstorms
are more common when the weather is warm and humid. This is because they form when
warm, moist air rises into the sky and causes clouds to build up. As the clouds continue to
grow, tiny particles of water and ice begin to collide, causing an electrical charge to build up
in the clouds. If the charge is great enough, lightning and thunder may occur.
Misconception 2: Is extreme weather unrelated to normal weather and climate
patterns?
The climate and weather patterns that result in normal weather are also the underlying
causes of most types of extreme weather.
What happens when weather
patterns produce too much or too
little precipitation?
Weather patterns that produce too much or too
little precipitation can have huge impacts on
local ecosystems. The two extremes of this type
of weather are floods and droughts. Floods occur
when there is too much precipitation and excess
water cannot be absorbed into the ground. An
especially dangerous type of flood is known as a
flash flood. These happen when water rises very
suddenly with little warning. Flash floods can
occur when a heavy rainstorm moves through an
area very slowly or when multiple storms cause a
great deal of water to end up in the same spot.
Flash floods can cause water to build up
on ground that is normally dry. Cars like
this one can stall and become stranded
during floods.
The opposite of floods are droughts, which are defined as long periods of little to no
precipitation. Droughts can cause plants and animals to die from lack of water. Droughts,
like all other types of extreme weather, are caused by normal weather patterns but can be
extremely hazardous to the areas they affect.
In this section, you will learn more about these and other types of extreme weather events
that may result from normal weather patterns.
Concept: Extreme Weather
Getting to Know
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© Discovery Education. All rights reserved.
Discovery Education is a subsidiary
of Discovery Communications, LLC.