Hurricanes are designated a rating to describe the overall strength and destructiveness of the storm system. Wind speed is the major factor that determines which category the hurricane belongs to. These categories are rated from 1 to 5 with 1 being the weakest state.
What is a hurricane?
A tropical storm system that produces winds with speeds of over 74 mph is called a hurricane.
Specifically, a hurricane is a type of tropical storm that normally forms over the Atlantic Ocean or eastern Pacific Ocean. There are other names given to tropical storms that occur in other areas of the world such as typhoon or cyclone.
The term typhoon is used to refer to a tropical storm that occurs in the western Pacific Ocean above the equator, and the term cyclone is used to refer to a tropical storm that occurs in below the equator and under the Asian continent. All of these tropical storms are capable of producing massive rainfall, large hail, thunder and lightning, and destructive, high-velocity winds.
How does a it form?
A hurricane needs to have certain environmental conditions be present for it to begin to form. First, there must be the presence of a body of warm water nearby. Considered to be the most important element for formation, warm ocean waters must be around 80 degrees Fahrenheit for at least 50 meters in depth to be sufficient for development. Although it is possible for these storm systems to form year-round, they are most likely to form during the summer months since conditions are more favorable. Winter and spring months do not see much tropical storm activity because air in the higher portion of the atmosphere is too turbulent to allow for production.
The next necessary element is wind. The winds come from the western direction from Africa to create Atlantic hurricanes. These winds cause water to evaporate as it glides across its surface and stimulates some of that water to evaporate and rise into the air. The higher the water vapor goes, the colder it gets until it completely condenses into liquid matter again, creating cumulonimbus, or storm-producing clouds.
Production of the clouds releases heat into the air, which then evaporates and condensates again to create more clouds. This process repeats itself over and over creating a group of storm-producing clouds and causing the wind to begin to swirl. At this stage, the phenomenon is known as a tropical disturbance.
As the cloud clusters continue to grow, air at the very upper portion cools at a rapid pace and causes a very unstable environment. But when the process continues and heat is released again, the air at the very top of the clouds gets warm and causes the air pressure to push winds away and outward. Pressures at the surface rapidly decrease and the surface air rises to create storms while winds continue to pick up speed. This is now a tropical depression.
The tropical depression evolves into a tropical storm when winds reach speeds of 39 mph. When the tropical storm has reached wind speeds of 74 mph, it finally becomes a hurricane. Hurricanes have a wide range of severity but one thing is certain–they are much more powerful when out at sea but lose much of their power once they hit land. This is because they have lost their main source of strength: the warm ocean waters.
Depending on where the storm system has formed, winds will spin in either the clockwise or counterclockwise direction. In the northern hemisphere, winds spin counterclockwise while in the southern hemisphere they spin in the opposite direction. This is called the Coriolis effect.
What are the different levels of strength?
Hurricanes are designated a rating to describe the overall strength and destructiveness of the storm system. Wind speed is the major factor that determines which category the hurricane belongs to. These categories are rated from 1 to 5 with 1 being the weakest state.
- Category 1: Wind speeds are at least 74 mph but no faster than 95 mph. The damage done when the storm has hit land can be described as minimal.
- Category 2: Wind speeds are at least 96 mph but no faster than 110 mph. The damage done when the storm has hit land can be described as moderate.
- Category 3: Wind speeds are at least 111 mph but no faster than 130 mph. The damage done when the storm has hit land can be described as extensive.
- Category 4: Wind speeds are at least 131 mph but no faster than 155 mph. The damage done when the storm has hit land can be described as extreme.
- Category 5: Wind speeds are at least 155 mph and have no upper limit. The damage done when the storm has hit land can be described as catastrophic.
A hurricane is just one of many natural disasters that we should be aware of and prepare for. Other natural disasters include flood, tornado, earthquake, wildfire, volcano, avalanche, lightning and tsunami.
