Saffir
/ Simpson Hurricane Intensity Scale
Category
One Hurricane:
Winds 74-95 mph (64-82 kt or 119-153 kph). Storm surge generally 4-5 ft
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.
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.
Category Three Hurricane:
Winds 111-130 mph (96-113 kt or 178-209 kph). Storm surge generally
9-12 ft above normal. Some structural damage to small residences and utility
buildings with a minor amount of curtainwall failures. Damage to shrubbery
and
trees with foliage blown off trees and large tress 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
nea
the coast destroys
smaller structures with larger structures damaged by
battering of floating debris. Terrain continuously lower than 5 ft 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.
Category Four Hurricane:
Winds 131-155 mph (114-135 kt or 210-249 kph). Storm surge generally
13-18 ft 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 ft above sea level may
be
flooded requiring massive evacuation of residential areas as far inland
as 6 miles.
Category Five Hurricane:
Winds greater than 155 mph (135 kt or 249 kph). Storm surge generally
greater than 18 ft 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
destructon 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 ft 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. Geoff Mackley may be in the area.
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