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Hurricane [[wind]]s swirl about the [[eye]], a calm area in the center of the storm. The band of tall, dark clouds surrounding the eye is called the eyewall. The eye is usually 10 to 40 miles in diameter and is free of [[rain]] and large [[cloud]]s. In the eyewall, large changes in [[pressure]] create the hurricane's strongest winds. These winds can reach nearly 200 mph. Damaging winds may extend 250 miles from the eye.

Hurricane [[wind]]s swirl about the [[eye]], a calm area in the center of the storm. The band of tall, dark clouds surrounding the eye is called the eyewall. The eye is usually 10 to 40 miles in diameter and is free of [[rain]] and large [[cloud]]s. In the eyewall, large changes in [[pressure]] create the hurricane's strongest winds. These winds can reach nearly 200 mph. Damaging winds may extend 250 miles from the eye.

Hurricanes are referred to by different labels, depending on where they occur. They are called hurricanes when they happen over the North Atlantic Ocean, the Caribbean Sea, the Gulf of Mexico, or the Northeast Pacific Ocean. Such storms are known as '''[[typhoon]]s''' if they occur in the Pacific Ocean west of an imaginary line called the [[International Date Line]], and '''cyclones''' if originating in the Indian Ocean, or the southwest Pacific.  

Hurricanes are referred to by different labels, depending on where they occur. They are called hurricanes if they occur over the North Atlantic Ocean, Caribbean Sea, Gulf of Mexico, or Northeast Pacific Ocean; '''[[typhoon|typhoons]]''' if they occur in the Pacific Ocean west of the [[International Date Line]]; and '''cyclones''' if they occur in the Indian Ocean or southwest Pacific.  

Hurricanes are most common during the [[summer]] and early [[Autumn| fall]]. In the [[Atlantic]] and the Northeast [[Pacific]], for example, [[August]] and [[September]] are the peak hurricane months. Typhoons occur throughout the year in the Northwest Pacific but are most frequent in summer. Approximately 85 hurricanes, typhoons, and tropical [[cyclone]]s occur in a year throughout the world.  

Hurricanes are most common during the [[summer]] and early [[Autumn| fall]]. In the [[Atlantic]] and the Northeast [[Pacific]], for example, [[August]] and [[September]] are the peak hurricane months. Typhoons occur throughout the year in the Northwest Pacific but are most frequent in summer. Approximately 85 hurricanes, typhoons, and tropical [[cyclone]]s occur in a year throughout the world.  

Names are assigned to [[Hurricane names|hurricanes]], typhoons and cyclones in order to differentiate between each years' storms. However, there is no universal naming convention, with hurricanes and Atlantic tropical storms being assigned male and female names, whilst the naming of a typhoon may differ from just being assigned a number (as in [[Japan]]), to being allocated an Asian name, as done by [[China]] and the [[Philippines]].  

Names are assigned to [[Hurricane names|hurricanes]], typhoons, and cyclones in order to differentiate between each year's storms. However, there is no universal naming convention.  Hurricanes and Atlantic tropical storms are assigned male and female names, whilst the name of a typhoon may be a number (as in [[Japan]]), or it may be assigned an Asian name, as in [[China]] and the [[Philippines]].  

==Classification==

==Classification==

==Hurricane conditions==

==Hurricane conditions==

Hurricanes require a special set of conditions, including ample [[heat]] and [[moisture]] that exist primarily over warm tropical oceans. For a hurricane to form, there must be a warm layer of water at the top of the sea with a surface temperature greater than 80 degrees [[Fahrenheit]]. Warm seawater evaporates and is absorbed by the surrounding air. The warmer the ocean, the more water evaporates. The warm, moist air rises, lowering the atmospheric pressure of the air beneath. In any area of low atmospheric pressure, the column of air that extends from the surface of the water or land to the top of the atmosphere is relatively less dense and therefore weighs relatively less.

Hurricanes require a special set of conditions, such as ample [[heat]] and [[moisture]], that exist primarily over warm tropical oceans. For a hurricane to form, there must be a warm layer of water at the top of the body of water with a surface temperature greater than 80 degrees [[Fahrenheit]]. Warm seawater evaporates and is absorbed by the surrounding air. The warmer the ocean, the more water evaporates. The warm, moist air rises, which lowers the atmospheric pressure of the air beneath. In any area of low atmospheric pressure, the column of air that extends from the surface of the water or land to the top of the atmosphere is relatively less dense and therefore weighs less.

Since [[air]] tends to move from areas of high pressure to areas of low pressure, wind is produced. In the Northern Hemisphere, the earth's rotation causes the wind to swirl into a low-pressure area in a [[counterclockwise]] direction. This effect of the rotating earth on wind flow is called the [[Coriolis effect]]. The Coriolis effect increases in intensity farther from the equator. To produce a hurricane, a low-pressure area must be more than 5 degrees of latitude north of the equator. Hurricanes seldom occur closer to the equator. For a hurricane to develop, there must be little wind shear, or in other words, little difference in [[speed]] and direction between winds at upper and lower elevations. Uniform winds enable the warm inner core of the storm to stay intact. The storm would break up if the winds at higher elevations increased markedly in speed, changed direction, or both. The wind shear would disrupt the budding hurricane by tipping it over or by blowing the top of the storm in one direction while the bottom moved in another direction.

Since [[air]] tends to move from areas of high pressure to areas of low pressure, wind is produced. In the Northern Hemisphere, the earth's rotation causes the wind to swirl into a low-pressure area in a [[counterclockwise]] direction. This effect of the rotating earth on wind flow is called the [[Coriolis effect]]. The Coriolis effect increases in intensity further from the equator. To produce a hurricane, a low-pressure area must be more than 5 degrees of latitude north of the equator. Hurricanes seldom occur close to the equator. For a hurricane to develop, there must be little wind shear— little difference in [[speed]] and direction between winds at upper and lower elevations. Uniform winds enable the warm inner core of the storm to stay intact. The storm would break up if the winds at higher elevations increased markedly in speed and/or changed direction. The wind shear would disrupt the budding hurricane by tipping it over or by blowing the top of the storm in one direction while the bottom moved in another direction.

== Bibliography ==

== Bibliography ==