Water Damage & Flooded Basement Restoration Services

How Hurricanes Form

By the RestorationSOS Educational Staff

Hurricane season lasts for about six months out of each year and the east coast keeps a cautious watch on the Atlantic Basin, wondering which of the numerous tropical depressions that crop up every year will develop into a full-fledged hurricane with its sights set firmly on their town.

After Hurricane Wilma in 2005, there wasn't another major tropical storm to hit the US until 2011's Hurricane Irene decimated much of the east coast from the Carolinas to New York City. Despite periods of inaction, the months of June through November remain a dangerous and unstable time. Property owners in hurricane-prone regions should be wary.

How Do Hurricanes Form?

Hurricanes begin their lives as clusters of clouds and thunderstorms known as tropical disturbances or depressions. Many of these blow themselves out without ever reaching tropical storm status, much less hurricane status. But there are the select few that are properly positioned and, as a result, grow stronger and more threatening over a period of a week or two. In such cases, thunderstorms in the disturbance release latent heat which causes air density within the disturbance to lower, with a corresponding reduction in surface pressure. Cooler air rushing in beneath the warmer air causes wind speeds to increase.

A hurricane should be thought of as a giant engine that utilizes warm, moist air as fuel (a clue as to why hurricanes rapidly blow themselves out once they make landfall). They form near the equator because of the abundance of warm, moist air rising from the surface of the ocean, creating a low pressure system that fuels and energizes the storm. Air from the surrounding higher pressure areas then pushes in to the lower pressure area, becoming warm and moist and rising into the upper atmospheric levels. This cycle is repeated and continues to provide strength and size to the hurricane until it is disrupted.

As the storm grows in size, it begins to rotate, fed by heat from the ocean as well as water evaporation. Storms forming north of the equator spin counterclockwise, while those south of the equator spin clockwise.

As the rotation increases, the eye of the hurricane forms in the center. This is an area of extremely low air pressure and is very calm and clear. Standing in the eye of the storm would lead you to believe that there isn't a storm anywhere in the vicinity.

Once hurricanes form, they move at various speeds across the ocean, gaining or waning in strength based on the amount of warm air and water available to them. Hurricanes may range in strength from Category 1 to Category 5, with 5 being the strongest, wind winds topping 155 mph and torrential rains. Only a few Category 5 storms have hit the US, such as Wilma in 2005, but the damage left behind can be overwhelming.

Recommended Reading
Preparing for Hurricane Season
Be Ready for Hurricanes
Staying Safe During a Hurricane