Weather Academy: Hurricane Formation
MONROE, La. (KNOE) - This month’s topic for the Weather Academy is hurricanes. We are all too familiar with hurricanes here in Louisiana, but are you aware of how hurricanes are formed?
Hurricanes start as storms over Africa. These systems will then move west, off the coast, and into the Atlantic Ocean. Once the storms get over the open ocean, they will have plenty of warm water to feed and fuel their growth.
These thunderstorms will be taking in the rising warm air. This will cause the storm to start to grow and become more organized. As these systems gain energy and grow, they’ll start to produce more rain as well as thunder and lightning. And as more warm air begins to rise, a low-pressure system forms below this system. This means that all of the air is above the surface, being pulled into the storm. Next, the trade winds will be picking up these storms from Africa and ushering them across the Atlantic Ocean.
The storm starts as a tropical depression. This is the weakest of the storm categories. A tropical depression is an organization of clouds and thunderstorms. It is just starting to circulate with winds less than 38 miles per hour.
Once the winds of our storm increase to 39 miles per hour, it is categorized as a tropical storm. Tropical storms are a little bit more organized than tropical depressions, with stronger thunderstorms and more circulation. Tropical storms have winds that circulate anywhere from 39 to 73 miles per hour. If winds increase and the system becomes more organized, it’ll strengthen into a hurricane.
In order to have a hurricane, you need to have intense organized tropical thunderstorms. Hurricanes also have powerful circulating winds of no less than 74 miles per hour. Some storms have circulating winds even faster than that.
There are three things needed to sustain a hurricane. Sea surface temperatures must be at or above 79 degrees. The storms also need weak wind shear, meaning that there is high pressure at the upper levels of the atmosphere. Weak winds shear prevents fast turning winds at upper levels that would disrupt the hurricane. The hurricane also needs to stay over the open ocean versus moving over land. Once a hurricane makes landfall, it becomes cut off from the warm ocean waters, which acted as its fuel source.
Join us all month on the Weather Academy as we dive into everything about hurricanes! Did you attempt one of our science experiments? Submit your photos and videos here. We might feature your photos in the next Weather Academy segment. Be sure to tune in next week as we make our own hurricane in a bowl.
Copyright 2021 KNOE. All rights reserved.