The Saffir-Simpson Hurricane Scale is used to describe the strength of hurricanes in the Atlantic and Eastern Pacific. Other scales are often used in other areas of the world.
The scale classifies hurricanes based on wind speed, pressure, and the height of the storm surge. The smallest hurricanes have wind speeds of 74 mph (119 km/h) while the largest hurricanes have wind speeds of over 155 mph (250 km/h). Storms that are smaller than hurricanes are given different names. Storms with winds less than 74 mph are known as tropical storms and storms with winds less than 38 mph are known as tropical depressions. These smaller storms can become hurricanes if they grow.
Greater than 980 millibars (mb)
74-95 miles per hour (mph)
4-5 feet (ft)
Damage mainly to trees, shrubbery, and unanchored
Some trees blown down; major damage to exposed
mobile homes; some damage to roofs of buildings
Foliage removed from trees; large trees blown
down; mobile homes destroyed;some structural damage to small buildings
All signs blown down; extensive damage to roofs,
windows, and doors; complete destruction of mobile homes; flooding
inland as far as 6 miles; major damage to lower floors of structures near
Less than 920 mb
Greater than 155 mph
Greater than 18 ft
Severe damage to windows and doors; extensive
damage to roofs of homes and industrial buildings; small buildings
overturned and blown away; major damage to lower floors of all structures
less than 15 feet above sea level within 500 yards of shore
Last modified February 17, 2009 by Lisa Gardiner.
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