In the United States, hurricane season starts on June 1st and doesn’t end until November 30th. There are an average of almost ten tropical storms and five hurricanes each year off the Atlantic coast. Hurricanes cause hundreds of millions of dollars worth of damages each year in the United States. But what is a hurricane? And what do those hurricane categories really mean?
What is a Hurricane?
A hurricane, or tropical cyclone, is a severe, rotating storm system which usually begins in the tropical waters of the Atlantic Ocean. In order to be classified as a hurricane, the storm system must have wind speeds of at least 74 miles per hour. If the storm has wind speeds of 34 to 73 miles per hour, then it is called a tropical storm. A storm with wind speeds of less than 34 miles per hour is known as a tropical depression.
Hurricane Categories: The Saffir-Simpson Hurricane Wind Scale
Classifying hurricanes is all about wind speed. The Saffir-Simpson Hurricane Wind Scale was devised in order to identify a potential hurricane’s intensity and the likely damage caused by its wind speed. There are five hurricane categories, ranging from least destructive (category 1) to most destructive (category 5). Notably, the scale does not take into account other potential damage from the storm, such as storm surge and flooding, since the severity of these effects are heavily dependent on local geography.
Category 1: A category 1 hurricane will have wind speeds between 74 and 95 miles per hour. At this speed, winds will cause minor property damage and injuries, largely due to flying debris and construction materials, such as roof shingles or siding. Since 1999, 7 category 1 hurricanes have made landfall in the United States.
Category 2: A category 2 hurricane will have wind speeds between 96 and 110 miles per hour. At this speed, winds can cause significant property damage and serious injury or even death. Winds are able to pick up and scatter debris, which can damage homes and businesses. Since 1999, 5 category 2 hurricanes have made landfall in the United States.
Category 3: A category 3 hurricane will have wind speeds between 111 and 130 miles per hour. At this speed, there is a significant risk of serious injury and death. Homes and businesses will sustain severe structural damage due to flying debris. Smaller and older homes or buildings may be completely destroyed. Since 1999, 7 category 3 hurricanes have made landfall in the United States.
Category 4: A category 4 hurricane will have wind speeds between 131 and 155 miles per hour. At this speed, there is a great risk of death or serious injury. Older and poorly build homes will most likely collapse while newer and well-built homes will sustain serious damage. Since 1999, only 1 category 4 hurricane has made landfall in the United States.
Category 5: A category 5 hurricane will have wind speeds of 156 miles per hour or more. At this speed, there is a great risk of death due to flying debris. Most buildings are at risk of collapsing due to high wind speeds and flying debris. At this speed, trees and signs are uprooted and cause serious injury to individuals and property. No category 5 hurricanes have made landfall in the United States since 1999.