Raymarine SR100 - Manual (Page 27)

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Hurricane A violent, spiralling storm that forms over the Atlantic Ocean, with winds over 120 kph. Such storms usually have a lifespan of sev
eral days. Also known as a typhoon or tropical cyclone. There are 5 levels of hurricane:
Category 1
Winds 74 95 mph (64 82 kt or 119 153 km/hr). Storm surge generally 4 5 ft above normal. No real damage to building struc
tures. 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 2
Winds 96 110 mph (83 95 kt or 154 177 km/hr). 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 dam
age to mobile homes, poorly constructed signs, and piers. Coastal and low lying escape routes flood 2 4 hours before arrival of
the hurricane centre Small craft in unprotected anchorages break moorings.
Category 3
Winds 111 130 mph (96 113 kt or 178 209 km/hr). 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 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 centre of the hurricane. Flooding near the coast destroys smaller
structures with larger structures damaged by battering from 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 4
Winds 131 155 mph (114 135 kt or 210 249 km/hr). 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 centre of the hurricane. 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 (10 km).
Term
Definition