When a hurricane is discussed on the news or in weather reports, it is often described as a “Category 1″ or higher storm. As the category number increases, the panic usually increases…and with good reason. Hurricanes of any category are powerful storms that merit our attention in order to preserve life and property.
There are five categories used to classify hurricanes, and each category has its own set of criteria and characteristics. The current system which is used to categorize hurricanes is known as the Saffir Simpson Hurricane Wind Scale. The scale was originally developed in the 1970’s by Herbert Saffir a wind engineer, and Bob Simpson a meteorologist. The scale was developed to measure the intensity of hurricanes, and was updated in 2010. Earlier versions of the scale took factors such as central pressure and storm surge into account, but the updated Saffir Simpson Hurricane Wind Scale does not. As we will see, the current scale addresses the wind intensity of hurricanes on a 1 to 5 categorization system. Let’s take a look at the five different categories of classification to better understand what the Saffir Simpson Hurricane Wind Scale is all about.
This is the category for the smallest hurricanes. However, many storms of this category can still pack a wallop because wind strength for this category is between 74 – 95 mph. At this level, limited structural damage to homes is possible, as well as damage to mobile homes and other small structures. Likely damages include shingle loss, vinyl siding loss and damage to sun-rooms, carports or lanais. Coastal flooding and destruction of piers is also likely to occur. Fallen trees and power lines are always a concern when strong winds are a factor, as well as window breakage due to flying debris. Commercial signs, canopies and fences could also be damaged. Rainfall at this level can be significant with inter-coastal flooding taking place. For this reason, a Category 1 hurricane should be taken seriously and appropriate safety measures should be taken to secure property and protect life.
Wind speeds increase as the Saffir Simpson Hurricane Wind Scale categories increase. Thus, a Category 2 hurricane is a more powerful storm than a Category 1 hurricane. This category is defined by increasing wind strength with speeds reaching between 96 – 110 mph. As you can imagine, the potential for structural damage increases, as well. Roofs, windows, shrubs and trees are likely to be damaged. A Category 2 storm will bring considerable destruction to mobile homes, apartment buildings and frame homes. Loss of electrical services is expected with power outages expected to last anywhere from several days to a few weeks. Clean water may become scarce as filtration systems fail. Hurricane Ike which struck the upper Texas coast in September of 2008 is a recent example of a strong Category 2 hurricane. This storm was the third costliest hurricane to ever make landfall in the United States and resulted in numerous deaths and casualties.
When Hurricane Katrina made landfall in southern Plaquemines Parish in Louisiana on August 29, 2005, she was a Category 3 hurricane with wind speeds reaching 125 mph near the center of the storm. Criteria for a Category 3 hurricane on the Saffir Simpson scale holds that wind speeds are 110 – 130 mph. As you can imagine, the damage such a storm inflicts will be significant and life-threatening. Poorly constructed homes will be destroyed in such a storm, having walls collapse and roofs blown away by the powerful winds. Well constructed homes will experience major damage, and nearly all mobile homes will be destroyed in such a storm. Metal buildings are likely to collapse, as well. Water and electricity will be unavailable for an extended period of time (from several days to several weeks) after such a powerful storm strikes. Perhaps one of the biggest lessons learned from Katrina is that citizens should have an emergency plan in place, as well as heed evacuation orders set forth by authorities. According to the NOAA, Hurricane Katrina was the most destructive hurricane to ever strike the United States.
With wind speeds between 131 – 155 mph, a Category 4 rating on the Saffir Simpson Hurricane Wind Scale is very serious business. Hurricanes of this strength will bring catastrophic damage to buildings, homes, windows, trees and community infrastructure. Power outages could last for weeks or even months. Areas affected could become virtually uninhabitable, and there is great risk of death and injury to people, livestock and pets. Hurricane Charley made landfall in 2004, striking the coastal area of Punta Gorda, Florida with Category 4 force winds. Hurricane Charley inflicted serious damage throughout the Florida peninsula, including massive property damage and loss of life.
Fortunately, only three Category 5 hurricanes have ever made landfall in the United States. Two such storms were Hurricane Camille in 1969 which struck the northern Gulf coast and Hurricane Andrew which devastated south Florida in 1992.
Wind speeds of hurricanes classified as Category 5 are greater than 155 mph, and the devastation inflicted will be the most severe of the previous categories. Complete structural failure for buildings is likely as roofs are blown off and utter destruction results. Loss of power and long-term water shortages are expected. Human suffering and loss of life is expected for those who did not evacuate from the path of the storm. Fortunately, improvements in technology have allowed meteorologists to better warn citizens of changing storm conditions. Certainly, nobody should be in the path of a Category 5 storm.
Scaling the Storm
As we can see from the Saffir Simpson Hurricane Wind Scale, a storm doesn’t have to rate a Category 5 to be the deadliest or costliest storm. Any hurricane rated Category 3 or above is considered a major hurricane. However, all hurricanes need to be considered carefully and watched closely. Weather conditions can change from one hour to the next as hurricanes are fluid, complex and ever-changing storm events.
The Saffir Simpson scale has been extremely helpful with meteorologists reporting hurricane conditions and developments to the public. Because of this, the general public is increasingly aware of what criteria each category level is about. This allows citizens to better prepare for the storm, and to take necessary precautions to safeguard their lives and property.
National Weather Service, National Hurricane Center http://www.nhc.noaa.gov/sshws.shtml