General Hurricane Information

Discover where and how hurricanes originate, and what gives hurricanes their destructive force.

Hurricanes are severe tropical cyclones, or storms, that occur during the summer months. They are a natural occurrence on the Eastern seaboard of the United States. Although the weather service has advanced methods now for the detection of hurricanes, the ferocity and damage that Mother Nature inflicts during the summer months still makes hurricanes a deadly event for those caught in its wake.

Hurricanes originate in equatorial regions of the Atlantic and Eastern Pacific Oceans every summer between the months of June and September near the western coasts of Africa. September is the most active month for hurricanes. They start out as a series of thunderstorms that come together to form a tropical wave, known as the hurricane seedling. The tropical waves evolve into stronger storms that drift north, northwest, or northeast. When the storms reach speeds of at least 74 miles per hour, they are classified as hurricanes. Hurricanes advance northward at speeds of 10 to 15 miles per hour. These same storms are called typhoons in the Western Pacific, and cyclones in the Indian Ocean. Ten percent of all tropical storms that arise become powerful enough to be classified as hurricanes.

Hurricanes are circular storms in which a calm center is surrounded by spiral clouds that spin inward towards the center. The center of the hurricane is called the eye of the storm. The eye is the low pressure area of the storm and can range from 5 to 15 miles wide. The clouds that circle around the eye form the eye wall. These spiral clouds carry the heavy rains and winds that are characteristic of hurricanes. The clouds can span many miles. However, the width of the storm clouds and eye can vary; usually, the more violent a hurricane, the smaller the eye, the larger the eye wall.

The driving force of the hurricane is water vapor. Water evaporates from the ocean's surface, which rises into the atmosphere, condenses, and then cools, releasing heat. When the heat gets pulled into the advancing eye of the storm, it gives the storm more energy, fueling its intensity. As the eye passes, it pulls the ocean waves several feet up, causing tidal waves which are pushed in front of the storm by the wind, creating storm surges that cause flooding to low-lying territories. When the hurricane does makes landfall, it progressively weakens because there is no longer any water source, and hence energy, to feed it.

The National Hurricane Center, which is run by the National Weather Service, is responsible for predicting and issuing warnings to people as to when a hurricane is expected to hit a particular area. A hurricane watch is announced when hurricane conditions are possible for a given area within the next 36 hours. A hurricane warning is issued by the Weather Center when a hurricane is expected over a region within the next 24 hours. The hurricane warnings generally involve evacuations of populations from low-lying land beneath sea level.

The National Hurricane Center rates hurricanes using the 5-point Saffir-Simpson scale, developed by meteorologist Robert Simpson and engineer Herbert Saffir. The Saffir-Simpson scale evaluates a hurricane's damage potential based on the storm's character.

A Category 1 hurricane will have winds of in the range of 74 to 95 miles per hour. Damage to unanchored boats and water craft will be sustained. Flooding in low-lying areas may also occur.

A Category 2 hurricane will typically have winds in the range of 96 to 110 miles per hour. A Category 2 hurricane will rip off roofing and cause damage to boats, windows, and mobile homes.

Hurricanes classified as Category 3 will experience wind speeds of 111 to 130 miles per hour. Structural damage will be incurred. People living in areas that are five feet below sea level will be evacuated.

Category 4 hurricanes will typically have wind speeds between 131 to 155 miles per hour. There will be extensive damage to the lower floors of structures and erosion of beach areas. People living on the ground in areas that are ten feet below sea level will be evacuated.

The most severe hurricane warning, Category 5, will require massive evacuations in low-lying areas within a ten mile radius. Winds in a Category 5 hurricane will exceed 155 miles per hour, and major damage is expected with this type of storm.

A severe hurricane can cause billions of dollars of damage to areas. Some areas in the United States are more prone to be hit by a hurricane than other areas. The areas most susceptible to severe damage in a hurricane are the Southern tip of Florida, the Outer Banks in North Carolina, and the Upper Gulf Coast.

People normally experience hard rain and wind when a hurricane hits, followed by periods of calm and blue skies, then more fierce rain and wind. The initial onslaught of the storm is in the form of the storm surge that precedes the actual storm. This is followed by heavy rain and hard wind. As the front of the storm passes inland, people can be lulled into a false sense of security that the storm is over when the eye passes and brings blue skies and calm winds. This can be dangerous because people will take to the outdoors, not realizing the back end of the storm has not yet hit. Before they know it, they are caught again by the wall of the storm. A hurricane with a great velocity will cause more damage because of the stronger wind. During hurricane conditions, people should stay away from the coastline because of the impending storm surge that comes before the actual hurricane strikes land.

Methods used to predict hurricanes have improved with time. Because a hurricane is a natural event, even a prediction may not anticipate the type of destruction that a hurricane will bring. As with any natural event, people should use caution and good judgment when dealing with Mother Nature.

Trending Now

© High Speed Ventures 2011