A hurricane is an intense, rotating oceanic weather system that possesses maximum sustained winds exceeding 119 km/hr (74 mph). It forms and intensifies over tropical oceanic regions. Hurricanes are generally smaller than storms in mid-latitudes, typically about 500 km (311 miles) in diameter. At the ocean’s surface, the air spirals inward in a counterclockwise direction. This cyclonic circulation becomes weaker with height, eventually turning into clockwise (anticyclonic) outflow near the top of the storm.


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Hurricane


Hurricane Katrina

kaitlyn 12-14-2010

Intensity Wind Speed Damage
Category 1 74-95 mph MINIMAL: Tree branches, shrubs, unanchored mobile homes
Category 2 96-110 mph MODERATE: Mobile homes, poorly constructed buildings, some trees down
Category 3 111-130 mph EXTENSIVE: Small buildings damaged, large trees down, mobile homes destroyed