Life cycle of a Tornado
Tornadoes usually come from a class of thunderstorms known as supercells. These supercells contain mesocyclones, an area of organized wind rotation a few kilometers up in the atmosphere. The biggest and most intensive tornadoes come from supercells. Not only tornadoes but also very heavy rain, frequent lighting, strong wind gusts and hail are also common in such storms.
Almost all tornadoes from supercells have the same life cycle. Which begins when the increasing rainfall drags the rear flank downdraft (RFD), an area of quickly descending air, with it. This downdraft increases in speed as it comes closer to the ground, and drags the rotating mesocyclone to the ground with it.
Formation:
When the mesocyclone is underneath the clouds, it begins to absorb cool, moist air from the RFD of the storm. The mixture of warm air in the updraft, and this cool air, causes a rotating cloud wall to form. The RFD also focuses the mesocyclone's base, causing it to flow air from a smaller and smaller area on the ground. As the updraft becomes stronger, it creates an area of low pressure on the ground. This pulls the mesocyclone down, in the form of a visible cloud funnel. As the funnels comes to the ground, the RFD also reaches the ground, creating a gust front which can cause a lot of damage close to the tornado.
Maturity:
After some time, the tornado has a good source of warm, moist air inflow to power it, so it grows and grows until it reaches it's "mature stage". This can last from a few minutes to an good hour, and during it mature stage the tornado often causes the most damage, and in rare cases can be more than 1.5 km across. At the same time, the RFD, now an area of cool surface winds, begins to wrap around the tornado, causing to cut off the inflow of warm air which feeds the tornado.
Dissipation:
As the RFD completely wraps around and chokes off the tornado's air supply, the vortex begins to weaken, and become thin and rope-like. This is the "dissipating stage", often lasting no more than a few minutes, after which the tornado fizzles. During this stage the shape of the tornado becomes highly influenced by the winds of the parent storm, and can be blown into fantastic patterns.[20][27][28] Even though the tornado is dissipating, it is still capable of causing damage. The storm is contracting into a rope-like tube and, like the ice skater who pulls her arms in to spin faster, winds can increase at this point
As the RFD wraps around and chokes off the tornado's air inflow, the vortex begins the weaken, and become thin and similar like a rope. This is called the "dissipating stage", which often lasts no more than a few minutes, after which the tornado fizzles. During this stage the shape of the tornado is influenced by winds of the original storm, and can be blown into some amazing patterns. Even though the tornado is fading away, it can still some heavy damage. The storms is contracting into a small rubber tube and winds can increase at this point. And then disappears.
This is only with big tornadoes coming from supercells. However most other kind of tornadoes also follow this same life cycle.
Almost all tornadoes from supercells have the same life cycle. Which begins when the increasing rainfall drags the rear flank downdraft (RFD), an area of quickly descending air, with it. This downdraft increases in speed as it comes closer to the ground, and drags the rotating mesocyclone to the ground with it.
Formation:
When the mesocyclone is underneath the clouds, it begins to absorb cool, moist air from the RFD of the storm. The mixture of warm air in the updraft, and this cool air, causes a rotating cloud wall to form. The RFD also focuses the mesocyclone's base, causing it to flow air from a smaller and smaller area on the ground. As the updraft becomes stronger, it creates an area of low pressure on the ground. This pulls the mesocyclone down, in the form of a visible cloud funnel. As the funnels comes to the ground, the RFD also reaches the ground, creating a gust front which can cause a lot of damage close to the tornado.
Maturity:
After some time, the tornado has a good source of warm, moist air inflow to power it, so it grows and grows until it reaches it's "mature stage". This can last from a few minutes to an good hour, and during it mature stage the tornado often causes the most damage, and in rare cases can be more than 1.5 km across. At the same time, the RFD, now an area of cool surface winds, begins to wrap around the tornado, causing to cut off the inflow of warm air which feeds the tornado.
Dissipation:
As the RFD completely wraps around and chokes off the tornado's air supply, the vortex begins to weaken, and become thin and rope-like. This is the "dissipating stage", often lasting no more than a few minutes, after which the tornado fizzles. During this stage the shape of the tornado becomes highly influenced by the winds of the parent storm, and can be blown into fantastic patterns.[20][27][28] Even though the tornado is dissipating, it is still capable of causing damage. The storm is contracting into a rope-like tube and, like the ice skater who pulls her arms in to spin faster, winds can increase at this point
As the RFD wraps around and chokes off the tornado's air inflow, the vortex begins the weaken, and become thin and similar like a rope. This is called the "dissipating stage", which often lasts no more than a few minutes, after which the tornado fizzles. During this stage the shape of the tornado is influenced by winds of the original storm, and can be blown into some amazing patterns. Even though the tornado is fading away, it can still some heavy damage. The storms is contracting into a small rubber tube and winds can increase at this point. And then disappears.
This is only with big tornadoes coming from supercells. However most other kind of tornadoes also follow this same life cycle.