April 23, 2012
Weather Education Episode #8: Components of a Thunderstorm
Red Orbit Meteorologist Joshua Kelly
In this lesson we will look at different components of a thunderstorm.
The first is the thunder which is the audio shockwave that is released just after a flash of lightning occurs. There is a rule of thumb that if you count the seconds after a flash of lightning to the sound of thunder you can determine how far away the thunderstorm is. For example if you count 5 seconds after a flash of lighting to the sound of thunder this would tell you the storm is 5 miles away.
The next component of a thunderstorm is the lightning. Lightning comes in various forms such as what is known as Cloud-Cloud, Cloud-Ground, In-Cloud and Cloud-Air. What this means is the way the lightning strikes work. For example, in the Cloud-Ground form, it tells us that the lightning is traveling from the cloud down towards the Earth´s surface.
The third part of a thunderstorm is the hail that it can produce. Recently in the Plains we saw hail that was as large as golf balls and even softballs. This hail can be very damaging to many things and if someone gets hit it can even cause personal injury.
Another feature of a thunderstorm is what is known as mammatus clouds. These types of clouds show a very unstable atmosphere with pockets of cold air sinking towards the ground which gives it the bubbly appearance that you see in the photo above.
Also, if the conditions are right, you can even get what is known as thunder-snow. When thunder snow occurs it creates very heavy snowfall amounts in a short amount of time.
The next feature is what is known as a gust front and wall cloud. Both of these clouds are found in a severe thunderstorm. A gust front indicates a horizontally rolling cloud, and when it arrives the winds can increase well over 70mph.. A wall cloud is a cloud that forms prior to the formation of a tornado. It is possible to see this cylindrical cloud and not have a tornado. It is important to know this cloud can lead to a tornado though.
Lastly we have the tornado or waterspout. Tornadoes form when all the conditions come together such as the warm moist air from the Gulf of Mexico and the dry air from the desert southwest and the cold dense air from the Colorado Rockies. A waterspout can form anytime there is rotation in the atmosphere and a cumulus-nimbus cloud or towering cumulus-cloud is present over the waters.
All of these things are what make thunderstorms one of the most amazing features on the planet. There are thunderstorms occurring on our planet every minute of the day. No matter if it´s in the middle of the United States or in the Tropics, there is always a thunderstorm happening.