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Stages of Hurricanes

The National Oceanic and Atmospheric Administration (NOAA) describes a hurricane as the most severe category of a "tropical cyclone." They are low-pressure systems that rotate counterclockwise and are accompanied by strong thunderstorms. Tropical cyclones are born in warm waters and begin as tropical depressions, grow to storms and then become hurricanes. Wind speed is what determines the level of a hurricane.

  1. Origin

    • For a cyclone to form, the ocean's temperature must be at least 80 degrees F to a depth of 150 feet. There must also be a low wind shear, meaning light upper level winds that don't change much in direction or speed.

    Saffir-Simpson Hurricane Scale

    • The Saffir-Simpson Hurricane Scale categorizes hurricanes on a scale of 1 to 5. It's based on the storm's intensity (wind speed). The scale is used to give an estimate of the potential damage a hurricane can do to property and the flooding it may bring in coastal areas.

    Category 1 Hurricane

    • A category 1 hurricane will have wind speeds of 75 to 95 mph. There may be some damage done to signs, unanchored manufactured homes, trees and minor flooding on coastal roads. There will be little to no damage to buildings.

    Category 2 Hurricane

    • Category 2 Hurricanes have winds between 96 to110 mph. Trees may be blown over. Parts of buildings including doors, windows and roofs may be damaged. Low-lying areas can expect flooding 2 to 4 hours before the center of the storm arrives.

    Category 3 Hurricane

    • Category 3 hurricanes carry winds between 111 to 130 mph. There may be structural damage to smaller homes and buildings. Trees and shrubbery can be blown over. Manufactured homes can be destroyed, and evacuations in some low-lying areas may be required.

    Category 4 Hurricane

    • Category 4 hurricane have winds between 131 to 155 mph. Expect extensive damage to doors, windows and smaller homes. Mobile homes can be completely destroyed. People living near shorelines may see flooding in the lower levels of their homes.

    Category 5 Hurricane

    • Category 5 hurricanes have wind speeds greater than 155 mph. Many homes may see their roofs destroyed, and there could be extensive damage to doors and windows. Homes within 5 to 10 miles of the shoreline may be evacuated.

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