Tornadoes are one of the most violent forces of nature on Earth. They occur in all 50 states and are spotted year-round. Although they are most common in the United States, Tornadoes can happen all over the world.
While tornado research has come a long way, there’s still a lot we know about tornadoes. They have been extensively studied over the past few decades to understand what causes them and how they form.
CNN meteorologist Brandon Miller, also a storm chaser, has been tracking and studying these storms since 2005.
“What you learn from studying tornadoes, especially in the field, is that there is no perfect formula for forming tornadoes — every storm is unique,” Miller said.
“Sometimes a storm appears to be in the perfect environment for a tornado to form, but it never does. Instead, tornadoes often form in marginal environments where one or more of the ‘ingredients’ for storm formation appear to be missing or lacking,” says M. Le said.
While there’s no perfect formula for which storms produce tornadoes, there are commonalities in the structure of systems that lead to tornadoes.
You can even see signs that will help you understand the life cycle of a developing storm that could produce a tornado.
As the warm air rises, the clouds start to get higher and higher. This is the development stage of a thunderstorm.you can see fluffy white Cumulus clouds getting higher is what you see for yourself. This is before you see rain or hear thunder.
As the cloud grows, you’ll notice that the base of the cloud darkens. Many times you will see the top of the cloud flatten out, forming an anvil shape protruding from the top of the cloud.
This indicates that the air at the top of the cloud is very cold and could be a precursor to the possibility of hail.
If the storm matures, it could become a so-called supercell. Supercells are spinning thunderstorms.
“Nearly all supercells produce some sort of severe weather (large hail or damaging winds), but only 30 percent or fewer produce tornadoes,” NOAA said.
During this mature stage of a thunderstorm or supercell; expect heavy rain, lightning, hail and strong winds.
Sometimes, moments before it rains, you feel a gust of wind. This is called a gust front. This is caused by cold air being forced down from the storm clouds. When cold air reaches the ground, it spreads quickly before a storm arrives. This is a sure sign that a storm is coming.
Tornadoes are usually formed from supercells. These supercells develop when there are multiple factors that help them thrive: instability, lift and wind shear.
In supercells, wind shear becomes an important component of storm development. Shear is when the wind changes direction with altitude. This creates rotation in the thunderstorm cloud.
Another force acting inside the supercell is the downdraft. This is an area of dry air pushed down from a storm. If it is forced to descend, it will wind up on the back side of the storm.
Updrafts and downdrafts work together to pull horizontal airflow down to form a tornado. This vertical column of air is called a funnel cloud until it touches the ground — at which point it becomes a tornado.
“When you look at close-in severe thunderstorms, the most obvious sign that a tornado may be forming is the ‘wall cloud,'” Miller said.
A wall cloud is a lowering of the cloud base that causes eddies, or swirling of the air.
When this spinning column of air touches the ground, a tornado forms.
The presence of a wall cloud doesn’t always mean a tornado will form, but it certainly increases the chances. “You’ll know you’re looking at a wall cloud because it’ll be significantly lower than the rest of the thunderstorm, and if you look closely, you’ll probably notice it’s spinning,” Miller said.
Most tornadoes are relatively small and short-lived, And still be dangerous and cause damage. However, more violent tornadoes can be more than a mile wide and stay on the ground for more than an hour. This is because they have much greater momentum than smaller tornadoes and are therefore harder to stop.
Miller has seen about 15-20 tornadoes in his storm-chasing years.
“There’s no denying that when you go out with the intention of seeing a tornado, there’s a certain level of excitement that comes with seeing a tornado,” Miller said.
“At the same time, you’re balancing that excitement with a fair amount of anxiety and concern about the possible impact of a tornado, especially if there are residents in the immediate path of the storm. As someone who has spent years researching and reporting on tornadoes, I still get nervous when you see a tornado in person.”
Smaller tornadoes have wind speeds of 60-110 mph, while more violent tornadoes have wind speeds of 160 to over 200 mph.
The May 3, 1999 tornado in Bridge Creek, Oklahoma had the strongest winds ever recorded on Earth, with winds exceeding 300 mph.