One of the most dramatic, damaging, and potentially
deadly events that occur in this country is a
hurricane.
Hurricanes are products of the tropical ocean and
atmosphere. Powered by heat from the sea, they are steered
erratically by the easterly trade winds and the temperate
westerly winds, as well as by their own energy. As they move
ashore, they bring with them a storm surge of ocean water
along the coastline, high winds, tornadoes, torrential
rains, and flooding.
Each year on average, ten tropical storms develop over
the Atlantic Ocean, Caribbean Sea, or Gulf of Mexico. About
six of these typically strengthen enough to become
hurricanes. Many of these remain over the ocean with little
or no impact on the continental United States. However,
about five hurricanes strike the United States coastline
every three years. Of these five, two will be major
hurricanes measuring a category 3 or higher (defined as
having winds above 111 miles per hour) on the
Saffir-Simpson
Scale. These storms can end up costing our nation
millions, if not billions, of dollars in
damages.
During a hurricane, homes, businesses, public buildings,
and infrastructure may be damaged or destroyed by many
different storm hazards. Debris can break windows and doors,
allowing
high winds and rain inside the home. In extreme storms
(such as Hurricanes Hugo, Andrew and Katrina), the force of
the wind alone can cause tremendous devastation, as trees
and power lines topple and weak elements of homes and
buildings fail. Roads and bridges can be washed away and
homes saturated by
flooding. Destructive
tornadoes can also be present well away from the storms
center during landfall. Yet,
storm surge alone poses the highest threat to life and
destruction in many coastal areas throughout the United
States and territories. And these threats are not limited to
the coastline -- they can extend hundreds of miles inland,
under the right conditions.
Courtesy of FEMA