In the 1970s the Saffir-Simpson hurricane intensity category system was developed to characterize the destructive potential of hurricanes. In addition to maximum sustained wind speed and central pressure, the Saffir-Simpson hurricane categorization includes storm-surge height and coastal destruction potential.

Left: The graphic was created by Lynn A. Dombrowski, Ed. D.

The Saffir-Simpson system sets the levels for hurricanes to five intensity categories, described in this chart under "Damage."

On average, there are about 10 named tropical storms off the east coast of the United States each year. Of these, 6 are likely to develop into hurricanes, but only 2 to 3 are likely to reach Saffir-Simpson category 3 or greater intensity.

Category 5 hurricanes are very rare, occurring about once every one hundred years. Recently, however, there have been several major hurricane events along the east coast of North America. In 1988 Jamaica and Mexico's Yucatan Peninsula were ravaged by category 5 Hurricane Gilbert. In 1989, category 4 Hurricane Hugo landed in Charleston, South Carolina killing 51 people and causing damage of over $6 billion. On August 21, 1992, tropical storm Andrew strengthened to hurricane proportions. Reaching category 5, Andrew was one of the most destructive storms ever recorded along the east coast, destroying more than 63,000 homes, causing $20 billion in property damage, and killing 27 people. Most of the destructive force from hurricanes is caused by high winds. Hurricane Andrew was pushed along by winds in excess of 120 mph. In addition, small whirlwinds were formed near the storm's center, and they picked up speed as they were pulled inward. These whirlwinds led to gusts of up to 80 mph, giving Andrew a destructive force of over 200 mph in some areas.

[ It's Raining Cats & Dogs ] [ What Are Hurricanes? ]
[ How Are Hurricanes Formed? ] [ Damage ]
[ Hurricane Intensity & the Saffir-Simpson Scale ] [ Naming Hurricanes ]
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