About Hurricanes
What Is a Hurricane?
Hurricanes,
tropical storms, and typhoons are collectively known as tropical
cyclones. They are among the most devastating, naturally occurring-hazard
in the United States and its territories. Tropical cyclones
are classified as follows:
Hurricane - An intense tropical weather
system with a well defined circulation and maximum sustained
winds of 74 mph (64 knots) or higher. In the western Pacific,
hurricanes are called "typhoons." Similar storms in the Indian
Ocean are called "cyclones."
Tropical Storm - An organized system of
strong thunderstorms with a defined circulation and maximum
sustained winds of 39 to 73 mph (34-63 knots).
Tropical Depression - An organized system
of clouds and thunderstorms with defined circulation and maximum
sustained winds of 38 mph (33 knots) or less;
Saffir-Simpson Hurricane Scale
|
CATEGORY
|
SUSTAINED
WINDS (mph)
|
DAMAGE
DEGREE
|
|
1
|
74-95
|
Minimal
|
|
2
|
96-110
|
Moderate
|
|
3
|
111-130
|
Extensive
|
|
4
|
131-155
|
Extreme
|
|
5
|
>155
|
Catastophic
|
What causes most of the hurricane-related
damage?
Storm surge, rain, and wind cause most of the
damage associated with hurricanes. · Storm surge floods and
erodes coastal areas, salinizes land and groundwater, contaminates
the water supply, causes agricultural losses, results in loss
of life, and damages structures and infrastructure. · Rain damages
structures, infrastructure, and agriculture and results in loss
of life. Hawaii's topography focuses the rains on mountain slopes,
causing flash flood
and landslides.
· Strong winds can result in loss of life, create tremendous
amounts of debris (which impact utilities and transportation),
cause agricultural losses, and destroy lightly constructed buildings
(e.g., tofu-block houses).