Different Types of Tornadoes

A tornado is characterized by a vertical column of air, with one end touching the Earth's surface and the other end is in contact with the dense heavy clouds. Usually, it rotates anti-clockwise at an extremely high speed. One common characteristic of all the tornadoes is that they are visible to us in the form of condensed funnels. These funnels are encircled by a cloud of debris and dust. The vortex of a tornado is produced due to some complicated energy transformations.

There are many different shapes and sizes of tornadoes. The shapes can vary from a rope-like structure to fat cylinders, and even conical or wedge-shaped structures. Some of the tornadoes that are discussed below are true tornadoes and some other like gustnado, firewhirl and dust devil are known as cousins of tornadoes, as they have tornado like structures.

Supercell Tornadoes
This type of tornado originates from supercell thunderstorms. The main characteristic of these storms is the presence of a thick upwardly drawn air current in a constant rotational motion, which is called mesocyclone. The tornadoes that are evolved out of these storms are big in size and are in the shape of a wedge. Supercell tornadoes tends to keep contact with the ground for a very long time and are extremely fierce in nature, with winds blowing at a speed above 200 mph.

Waterspout
This type of tornado is formed above the surface of water. There are two types of waterspout tornadoes - tornadic and non-tornadic or fair-weather. Tornadic waterspouts are mesocyclonic tornadoes that are formed over the surface of water. Since they are developed from thunderstorms, they possess high speed and intensity, and are terribly destructive in nature. On the other hand, fair-weather waterspouts are far less destructive. They are not a very strong kind of tornado. Their winds are weak in nature and move quite slowly. The intensity of a non-tornadic waterspout is weakened further when it reaches the land surface.

Landspout
The other name of landspout tornado is dust-tube tornado. This type of tornado is of much lesser intensity as compared to a supercell tornado and they are of shorter duration. It does not have any kind of association with mesocyclone. Even though it is a weaker form of tornado, it yields quite strong winds that are capable of inflicting massive damage. Usually, the smooth condensation funnel of landspout is not in touch with the ground. However, when it makes contact, a thin layer cloud of dust is formed.

Gustnado
A gustnado can be defined as a gust front tornado. It is a weak tornado that do not last for a long period of time. Technically, there is no link between the cloud base and the circulation of the wind. Hence, it is not considered as a tornado. It is a temporary whirl of dust and debris, confined to a small area with a heavy rotational wind. They look similar to dust devils.

Dust Devil
Dust devils can be observed on any dry and hot days on a dry piece of land or desert. The unique feature of a dust devil is that they are formed under clear sky and are not associated with any cloud like other tornadoes. They occur mainly during late hours of the morning or early hours of the afternoon. It is a whirlwind that blows at a speed of 70 mph and creates a thin vortex of dust. The intensity of the dust devil is weaker than even the weakest of all tornadoes and is absolutely harmless in nature.

Firewhirls
Firewhirls are often referred to as fire tornadoes, firenadoes or firedevils. The heat created by a wildfire or volcanic eruption causes firewhirls. It consists of a column of rotational smoke or fire which looks like a tornado. The wind speed of firewhirls is usually above 100 mph.

Tornadoes can take place anywhere in the world, except in Antarctica. However, it is more frequently observed in southern Canada, southeast Europe, parts of South America, Australia and New Zealand.