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Two of EarTh’s mighTiEsT and most devastating storms are
tornadoes and hurricanes. a tornado’s killer winds can reach 300 mph
(400 km/h)—strong enough to lift cars, mobile homes, and people
into the sky. with speeds of up to 200 miles (320 km) an hour,
a hurricane’s winds can uproot trees and lift roofs off buildings.
Tornadoes and hurricanes develop from and are fed by warm,
moist air. Both bring driving winds, heavy rain, hail, and low
air pressure that can devastate a region. however, several
characteristics separate the two kinds of storms. Tornadoes form
on land, while hurricanes develop over oceans. a tornado twists in
a funnel-shaped column, while a hurricane swirls around a calm
center called the eye. a tornado strikes quickly and with little
warning, while a hurricane is much larger and can rage for days.a TwisTEr sTrikEs
Tornadoes, also known as twisters, are born
from severe thunderstorms. moist, warm
air rises until it meets a higher layer of
cooler air. storm clouds grow as the
trapped air cools and rain forms. air
rushing in to replace the rising air creates
strong winds that spiral upward, whipping
dust and debris into a huge, black cloud.
The deadly spiral of air cuts its path across
the land. The United states, particularly
the midwest, is hit by over 1,000 tornadoes
a year—more than any other country.BirTh of a hUrricanE
hurricanes develop from warm,
moist air over tropical oceans. The
air flows into low-pressure areas,
where it rises and cools to form
clouds. more warm air is drawn
upward, creating winds; the spin
of Earth causes the storm winds to
circle around a low-pressure area
at the center of the storm called
the eye. most of these storms die
out and never reach land. however,
in a typical year, six hurricanes hit the
gulf of mexico and the atlantic coast
states during “hurricane season,”
from summer to early fall.Tracking a sTorm
meteorologists (weather scientists) gather information
from weather balloons, satellites, and radar to predict
and track storms. specially equipped planes, known as
hurricane hunters, fly directly into the eye of hurricanes to
measure wind speeds, temperatures, and humidity.
computer programs assess the data
to help predict the path
of the hurricane. sTorm sUrgE
The most dangerous part
of a hurricane is its storm
surge—a huge mass of water that piles up under the
storm. as the bulging dome of water reaches shallow
waters near the shore, the surge slows down before
rising to drown the coastline, swallowing boats and
houses and flooding the land. in 1900, a hurricane in
galveston, Texas, created a surge that killed 6,000
people—the worst natural disaster in american history.Taking a ToLL
The awesome power of
tornado and hurricane winds
can bring sudden and
widespread destruction. such
was the case of hurricane
katrina in 2005, during
which more than 1,800
people died and more
than $81 billion dollars in
damage was reported.Tornadoes and hurricanes
A tornado has cut a devastating
path through this town
in Kentucky.storms
water
weather
windFind out more
US_523_Tornadoes.indd 523 29/01/16 10:30 am