The Saffir-Simpson Hurricane Scale is a 1-5 rating based on the hurricane's present
intensity. This is used to give an estimate of the potential
property damage and flooding expected along the coast from a
hurricane landfall. Wind speed is the determining factor in the
scale, as storm surge values are highly dependent on the slope
of the continental shelf in the landfall region. Note that all
winds are using the U.S. one-minute average.
Category One Hurricane:
Winds 74-95 mph (64-82 kt. or 119-153 kph). Storm surge generally
4-5 feet above normal, no real damage to building structures.
Damage primarily to unanchored mobile homes, shrubbery, and trees.
Some damage to poorly constructed signs. Also, some coastal road
flooding and minor pier damage. Hurricanes Allison of 1995 and
Danny of 1997 were Category One hurricanes at peak intensity.
Category Two Hurricane:
Winds 96-110 mph (83-95 kt or 154-177 kph). Storm surge generally
6-8 feet above normal, some roofing material, door, and window
damage of buildings. Considerable damage to shrubbery and trees
with some trees blown down. Considerable damage to mobile homes,
poorly constructed signs, and piers. Coastal and low-lying escape
routes flood 2-4 hours before arrival of the hurricane center.
Small craft in unprotected anchorages break moorings. Hurricane
Bertha of 1996 was a Category Two hurricane when it hit the North
Carolina coast, while Hurricane Marilyn of 1995 was a Category
Two Hurricane when it passed through the Virgin Islands.
Category Three Hurricane:
Winds 111-130 mph (96-113 kt. or 178-209 kph). Storm surge generally
9-12 feet above normal, some structural damage to small residences
and utility buildings with a minor amount of curtain wall failures.
Damage to shrubbery and trees with foliage blown off trees and
large trees blown down. Mobile homes and poorly constructed signs
are destroyed. Low-lying escape routes are cut by rising water
3-5 hours before arrival of the hurricane center. Flooding near
the coast destroys smaller structures with larger structures
damaged by battering of floating debris. Terrain continuously
lower than 5 feet above mean sea level may be flooded inland
8 miles (13 km) or more. Evacuation of low-lying residences with
several blocks of the shoreline may be required. Hurricanes Roxanne
of 1995 and Fran of 1996 were Category Three hurricanes at landfall
on the Yucatan Peninsula of Mexico and in North Carolina, respectively.
Category Four Hurricane:
Winds 131-155 mph (114-135 kt. or 210-249 kph). Storm surge generally
13-18 feet above normal, more extensive curtainwall failures
with some complete roof structure failures on small residences.
Shrubs, trees, and all signs are blown down. Complete destruction
of mobile homes. Extensive damage to doors and windows. Low-lying
escape routes may be cut by rising water 3-5 hours before arrival
of the hurricane center. Major damage to lower floors of structures
near the shore. Terrain lower than 10 feet above sea level may
be flooded requiring massive evacuation of residential areas
as far inland as 6 miles (10 km). Hurricane Luis of 1995 was
a Category Four hurricane while moving over the Leeward Islands.
Hurricanes Felix and Opal of 1995 also reached Category Four
status at peak intensity.
Category Five Hurricane:
Winds greater than 155 mph (135 kt. or 249 kph), storm surge
generally greater than 18 feet above normal. Complete roof failure
on many residences and industrial buildings. Some complete building
failures with small utility buildings blown over or away. All
shrubs, trees, and signs blown down. Complete destruction of
mobile homes. Severe and extensive window and door damage. Low-lying
escape routes are cut by rising water 3-5 hours before arrival
of the hurricane center. Major damage to lower floors of all
structures located less than 15 feet above sea level and within
500 yards of the shoreline. Massive evacuation of residential
areas on low ground within 5-10 miles (8-16 km) of the shoreline
may be required. There were no Category Five hurricanes in 1995,
1996, or 1997. Hurricane Gilbert of 1988 was a Category Five
hurricane at peak intensity and is the strongest Atlantic tropical
cyclone of record.
Hurricane
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