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Like a river's flow, it never ends...
Jun 2, 2009
I'm sure you guys have heard about the violent storms that have ravaged parts of the Southern US. Storms that produced strong tornadoes and caused major damage and power outages across many counties in Mississippi, Alabama, and Tennessee. These storms have caused many deaths as well as the death toll is currently at 281 and will more than likely rise since search-and-rescue efforts are still going on.

Anyway due to these things occurring as well as having one nearly hit my current place of residence, I've decided to talk about tornadoes. More specifically the basic information of a tornado, how they are formed, common myths about tornadoes, and what to do to prepare and protect yourself in the event of having one headed your direction.

Basic Information

A tornado, is simply put a rotating column of air that is usually connected to the clouds above it and is touching the ground. For those of us who live in the US, tornadoes usually are formed in what is known as "Tornado Alley".

This is an area that is located between the Rocky and Appalachian Mountains. There are more stronger tornadoes that are formed here than anywhere else. There is also a "Dixie Alley".
This alley compasses most of the southern states as well as some of the northern states above them. Most tornadoes that form there tend to be very violent and last a lot longer than most tornadoes do. Also tornadoes tend to form during the evening hours when the tornadoes cannot be seen by storm spotters. Tornadoes in this area tend to be also blended in with the clouds or be hidden behind trees and hills which makes them harder to see. Tornadoes can also have different shapes such as the normal appearance is seen most of the time, a wedge shape, and a rope-like look.


Like hurricanes, the strength of tornadoes are categorized by a scale. There are three types of scales that are used to classify a tornado's strength which are: the Fujita Scale, the Enhanced Fujita Scale, and the TORRO scale. The Fujita and Enhanced Fujita Scale both use a 0-5 strength category, but they each have a differences. The Fujita scale uses a letter 'F' in front of the number and the Enhanced Fujita scale has the letters 'E' and 'F' in front of it and both scales has different wind speeds for each category. For instance for the Fujita scale the strength of tornadoes are classified as:

F0= wind speeds of 40-72 mph (64-116 km/h) and a 10-50 width (meters). These tend to cause relatively little damage such as downed trees, road signs being damaged, branches being broken off, etc.

F1= wind speeds of 73-112 mph (117-180 km/h) and a 30-150 width (meters). These cause some more damage as compared to the F0. Examples of this type of tornado can be the peeling of roofs of homes, mobile homes are pushed off of their foundations, and cars can be pushed off the roads.

F2= wind speeds of 113-157 mph (181-253 km/h) and 110-250 width (meters). This is where it starts to get bad. Roofs can be torn off of houses, mobile homes destroyed, trees can be snapped and uprooted, windows can be broken or blow in, and light objects can be thrown by the tornado and become like missiles.

F3= wind speeds of 158-206 mph (254-332) km/h) and 200-500 width (meters). It only gets worse here. Roofs and walls of homes can be torn off, most trees are uprooted, skyscrapers can be twisted and deformed with a lot of damage to the interiors of the building and cars can be lifted off of the ground and thrown.

F4= wind speeds of 207-260 mph (333-418 km/h) and 400-900 width (meters). This is one of the strongest tornadoes that one can experience. Homes are leveled and can be blown away some distance, trains can be overturned, Cars are thrown and large objects can be used as missiles, and skyscrapers and highrises can be toppled or destroyed.

F5= wind speeds of 261-318 mph (419-512 km/h) and 1,100- (any higher number) width (meters). This is the strongest tornado to exist based on the Fujita scale. A tornado of this strength can lift strong frame houses off of it's foundations and be carried for a large distance and disintegrate, cars can be thrown an excess of 100 m (109 yds). Trees are stripped of their bark and steel reinforced buildings are badly damaged.

The Enhanced Fujita Scale follows the same pattern of 0-5 but the wind speeds are different.

EF0= wind speeds of 65-85 mph (105-137 km/h)
EF1= wind speeds of 86-110 mph (138-178 km/h)
EF2= wind speeds of 111-135 mph (179-218 km/h)
EF3= wind speeds of 136-165 mph (219-266 km/h)
EF4= wind speeds of 166-200 mph (267-322 km/h)
EF5= wind speeds of 200 mph or greater (322 km/h or greater)

As for the TORRO scale this measures a strength of a tornado but a range from T0 to a T11; T0 being no tornado on the ground, just a funnel cloud and T11 being a seriously devastating tornado(equivalent of a EF5 or F5 tornado). It mainly measures wind speeds and is sometimes used in weather reports when they are reporting on possible tornadoes.

Here are some photos of damage that tornadoes can cause depending on their strength:

Formation of Tornadoes
Tornadoes usually are formed during what is called “supercells” during a thunderstorm. These contain mesocyclones (which is an area of organized rotation a few miles up in the atmosphere and usually 1-6 miles across (2-10 km)). When these supercells form a tornado they can make the classic “hook echo” or sometimes a kidney bean shape when the hook echo cannot be seen. This was the case in at least one of the tornadoes that caused so much damage on April 27, 2011.

When the hook echo appears it is the first sign that a tornado is forming. The mesocyclone will go to the ground and at time will form a rotating wall cloud. When it descends something called the Rear Flank Downdraft (RFD) comes down with it and the funnel cloud will become a tornado within minutes of it reaching the ground. It then uses what warm, moist air it has to grow and travel across the ground until it runs out. This can last from a few minutes to more than an hour and it causes most of it's damage then. They can also grow to be more than a mile (1.6km) across at this time of development.

At this time the RFD (which is now cold air) begins to make it's way around the tornado and cuts off it's supply of warm air. After this is done, it will begin to grow away and become thin and rope-like. It can still cause damage at this time as well. It doesn't last more than a few minutes and after this part is done, that tornado is no more. The cycle can begin again and the same supercell can create more tornadoes that can cause more damage.

Video of tornado forming:

Common Myths
There are some myths regarding the formation of tornadoes about where they can only form and ways to protect yourself. One myth is about the idea that tornadoes cannot form near major cities or near major rivers, hills, or mountains. In truth they can form there and they have been known to cross rivers and mountains. One example of a tornado landing near a major city is one that landed in the downtown area of Salt Lake City, Utah.

Another one is that it is commonly thought that tornadoes can form only in the US. In actuality they can form anywhere and on any continent. There have been cases where they have formed in Australia, the United Kingdom, Russia, Bangladesh, and the Philippines. The only place where no case of a tornado has not been reported is Antarctica.

One other myth regards seeking shelter under an overpass. Experts have found that this actually really doesn't do anything to protect you and could actually kill you if you were to seek shelter. It causes a wind-tunnel effect under the underpass and can actually increase the wind speed.

One last myth I will cover is the one that tornadoes do not form in winter. In actuality they can. These tornadoes are very rare, since it is found that they need to warm air in order to help form their creation. These winter tornadoes are in actuality more deadly than those that are formed in the other seasons, because they move faster in the winter.

There are more myths than the ones I covered, these are just the basic ones that I hear most of the time about tornadoes.

Ways to Prepare

There are ways that you can prepare yourself for a tornado. First off you need to have a plan set in place so that everyone will know where to go in the event of a tornado heading in your direction. A basement, a storm shelter, a bathtub, or in interior room such as a closet or hallway are good places to take shelter. Also make sure that the place that you're taking shelter in is on the lowest level of you home, if it is an apartment complex that'll be the ground floor. If in the event you are out in your car when the tornado occurs experts say that it is best to get down in a ditch or if you can find a form of shelter in the area you are driving in to go there.

Something else you can do is get supplies to prepare for the moment since the last thing you need to do is leave the place that you're taking shelter in. An AM/FM radio, batteries, flashlights as well as pillows or blankets that you can use to cover yourself are examples of these supplies. These supplies need to be stored in the area that you're taking shelter or in a container that you can easily access and carry to your safe area when the time arises. Time is of the essence, especially in this kind of emergency. Also in the event of you losing your power due to a tornado and your home is not damaged you need to stock yourself up on some candles, matches, lighters, bottled water, and food that can be cooked over a gas stove or fire. Another thing I recommend is getting a generator as well as tank of gasoline to help run the generator. It's best to keep the generator up to date because in the event of a power outage you will be unable to go purchase parts or gas due to electricity being how most of that is supplied. Check it once every month as well as go over your safety plan to ensure that you'll be prepared for the moment that it happens. Also make sure that when you use the generator that you keep it outside as it can cause you to suffocate if you were to put it in your house. Another thing I recommend is saving up some emergency cash just in case something like this does occur. Because in the case of a power outage, you will more than likely be unable to use a debit/credit card to purchase something. With cash on hand you can feel assured that you have some way to pay for last minute supplies when the power is out. And one last thing I can recommend (if you do not have sirens or some other type of warning system in your area) is to subscribe to weather alert system (such as what the Weather Channel has; and don't worry they won't charge you for that service. It all depends on your cell phone plan.). This way you will know when your area has a Tornado Watch or a Tornado Warning as soon as they get the information.

And that is the end of my speech on tornadoes. I hope that none of you guys have to go through any of this since these things can move fast and quick. They can level entire towns and can be upon before you know it. The only way to ensure that no loss of life occurs is if everyone prepares for this type of emergency because you never know when it might happen. It could sneak up on you when you least expect it.
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Sep 16, 2009
Cali For Nuh
This was very insightful knowlee... Where I live in California it makes it very difficult for tornado to form. However we've seen them try. If they are ever successful I now know what to do.


Collecting Dust
Sep 27, 2010
I'm so glad I live in somewhere where tornados are rare. The only tornado I have heard of near us was just like a strong wind and it withered and died in about one minute.

I am sorry for whoever died and let them rest in peace.


Dec 1, 2009
That place where things are.
You know, I always thought I know most of the stuff relating to tornadoes I'd ever need to know, but I never knew about "Dixie Alley" until this topic came around, which answers why we seem to get so many tornadoes around here without actually being in Tornado Alley. Along with that, although I knew all the stuff to do if one comes through, there's no real place near here that would be able to withstand a tornado that's stronger than an F0, so I'd be pretty screwed if one hit head on.

But regarding the recent outbreak, being in TN, I wound up having quite a few tornadoes barely miss me, along with that one supercell that formed in amongst all the storms, not to mention watching funnel clouds form directly above where I was. It was one of the scariest things I think I had ever went through.


I don't suffer from it ..
Jun 17, 2010
Where I live we have our share of Tornado watches and warnings, but if they do form they rarely touch down and do significant damage. We do have to be on the lookout for hurricanes though.


Feb 25, 2010
Where I live there are very rarley tornados, but just yesterday a tornado was spotted in a lake near my town.


~Dancer in the Dark~
Jan 30, 2010
I applaud you for your efforts on this, knowlee. I have never seen a tornado in my life, I doubt I ever will but I hope everyone stays safe! And now they know what to do incase a tornado forms where they are.


Dec 3, 2009
Ikana Canyon
I used to live in Tornado Alley but now I live in Canada. Back in Texas we would get a lot of warnings and Tornado watches but they never really touched down well not in my life time. Our town had a really bad Tornado but that was way before I was born and my mom was a little girl when it happened to her. My old town likes to call that day Terrible Tuesday and apparently it was a F4 or F5 but I can't remember which one. I'll pray for those who have been affected by the Tornadoes in Mississippi, Alabama, and Tennessee. Tornadoes can be a very scary thing I'm glad that I was never affected by one.

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