Atmosphere And Weather

The Anatomy of a Tornado

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"The Anatomy of a Tornado"
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There are several ways to describe the beauty and wonder of Mother Nature's creations, but not many words can explain her much darker side that lurks within the thunderheads of an unstable storm system. Crystal blue skies and soft lofty clouds can soon be twisted and contorted into swirling dark cloud masses; melting a once portrait of summer perfection, sending you head-long into the midst of a tornado producing storm.

Maybe I am being just a little melodramatic, but for those of you that have ever experienced the terror and fury of a tornado firsthand, you know otherwise! So what exactly fuels these black monsters that fall from the clouds? And when is a Tornado just a sight to behold, and not a force to be reckoned? I would like to present a crash course (pardon the pun), on Tornadoes.

A tornado can appear as a long snaking rope draping across the sky; it can also take the form of a cone or funnel comparable to the end of an inverted tuba. They require a specific set of conditions to gather enough strength to create the rotation, but once this fuel is injected, these beasts can drop from the sky like an atomic bomb leveling anything in its path.

The nuts and bolts:

The formulation of a tornado is not quite an exact equation, but it does require some specific ingredients to fuel the fire, so to speak. For the sake of this article, I will describe this process based on the most common region that is affected by the greatest numbers of tornadoes. First you need a nice warm humid air mass that usually comes up from the Southern Gulf of Mexico, and next you introduce some cooler air mass from the Northern Canada region, and mash them together with the aid of some forceful barometric pressure, and voila you have a basic storm cell. Now not all storm cells are tornadoes in the making, but if these two air masses continue building, than it forms a more unstable system known as a "super cell".

So now you have a highly unstable super-cell. But is that all it takes to unleash a twister? Not quite, but with a few more tweaks from Mother Nature, like a nice variation in wind direction, coupled with an increase in wind speed; and soon the pot begins to stir. This stew of meteorological conditions is what begins a rotation in the lower part of the atmosphere, which the spinning effect can begin to pull rising air within the updraft; or the engine as some storm chasers call it. Due to the growing wind velocity the once horizontal churning, tilts on its side to become a fully vertical funnel cloud. Now, as long as the updraft and pressure remains constant, the rotation will now have extended across the largest part of the super-cell. Brining us to the final stage, where the storm can stall (rotation stops or pauses) or dissipate into nothing, or it can drop a funnel cloud to the surface of the earth forming a fully developed tornado.

Tornadoes at this point can be either very large, with sluggish rotation, or they can have extremely high wind velocities that can continue building. Sluggish storms, may occasionally stall from time to time, which either start back up as it begins building more momentum, or it again it may just vanish into thin air, at which time the cell dissipates into a somewhat more stable thunder storm system. However, if the wind speed increases and it maintains enough rotational velocity the tornado can continue traveling great distances until the system is finally without the proper ingredients that prevent the rotation from collapsing; thus ending the tornado.

Some of the most massive storm systems are so unstable that they are capable of producing multiple super-cells, which can form a series of sister tornadoes. Such storm lines are known to have severe and unimaginable damage to any type of ground based structures.

The Scientific measurements:

A man by the name of Tetsuya "Ted" Fujita developed a scale in which to measure the various wind velocities of a given tornado. Himself along with Allen Pearson were the first members to head the National Severe Storms Forecast Center. The Fujita scale is still used today to measure how powerful a tornado actually becomes from its first touchdown, to the last gust it blows, before disappearing back into the clouds. The scale is actually quite simple, but at the same time, equally as frightening.

Category F0: This tornado is sometimes referred as a small funnel cloud or twister, and it can have wind velocity ranging between 40-72mph, and it can cause light to moderate damage.

Category F1: This is a more common occurring tornado, and it can cause medium to moderate damage, such as peeling shingles or tearing roofing, downing trees, and at the higher scale it can even push or overturn a vehicle. This menace has a wind velocity ranging between 73-112mph.

Category F2: Now the potential for damage is getting more severe! With wind velocities ranging at 113-157mph, now motor homes become play-toys, and freight cars can be flipped, and large trees can either be snapped of fully uprooted.

Category F3: This is where storms really pack a hefty punch. These tornadoes range between 158-206mph, and now homes can be torn apart, trains overturned, entire forests leveled, and heavy vehicles can be lifted straight off the ground, and be tossed a great distance.

These next three categories are unlike any other storms, they are the line that gets crossed between damage and destruction. Like the four horsemen galloping across the sky, these tornadoes are the messengers of untold darkness!

Category F4: This class is considered on the devastating range, with furious winds ranging between 207-260mph. With sustained winds of this magnitude well constructed houses can be leveled to splinters, cars are thrown like missiles, and barely anything will not sustain at least minimal damage.

Category F5: The range class is considered incredible damage, and rightfully so. Known to storm chasers as "the finger of God", the wind velocity ranges between 261-318mph, and it can lift even the strongest framed houses clear off their foundation with ease. Most houses are either damaged beyond repair or disintegrate after being dropped considerable distances away. Cars can be carried within the vortex for long periods gathering speeds of over 100mph before being hurtled back to the ground. Steel reinforced concrete structures suffer extreme damage, and barely anything remains unscathed.

Recently due to severe weather patterns most scientists predict that storm severity is on the rise, mainly due to global warming, and a new class of super storms may be the result. This leads me to my final; and I hope I never see this day. The most inconceivable Tornado would be the Category F6. If an F5 is considered the "finger of God", than an F6 would undoubtedly be the Grim Reaper of storms. Many argue over whether such a storm is either conceivable, or if one or two may have already touched down. But with wind speeds ranging between 318-400mph, this tornado could theoretically obliterate houses, lift small duplexes or buildings, and would carve a path almost five or six feet into the ground shearing pavement and earth beneath its destructive trail.

Tornado theories and such:

Tornadoes don't follow specific rules of engagement since they can appear to bounce as rotation suddenly stalls, which gives the appearance as though the tornado is being sucked back into the sky, only to be spat back to the ground to continue destroying. They move with no inherent reason sometimes carving a straight path, and other times zigzagging until they finally vanish into thin air. Some tornado producing storms are layered with other weather conditions like thunder and lightning, snow, hail storms, and other times they can seem eerily calm.

The Myths:

1.) Yes, you are risking your life if you think you can out-run a tornado. Most tornadoes move at incredible land speeds and can quickly sidestep, or jump into your path.

2.) Overpasses and trees are safe refuge from a tornado. Honestly, there is no safe place from a larger class tornado, and since they travel at ground level an underpass does not get below this path, so it will not stop or protect against the impending twister.

3.) Opening windows will make you safer. Opening doors and windows do not equalize pressure, and do not allow flow through, but it will allow wind surges to tear the inner part of your home, vehicle or whatever, not to mention the debris field. Note: I have seen a toy car not only pass through a solid formed dry wall, but it continued at such a velocity that it sailed straight into the chest of a person cowering in the closet, which it impaled him (luckily he lived)!

4.) The most southern west corner of your home is not the safest location to be during a tornado storm! This one can only be true if the tornado is approaching from the opposite direction, but honestly the safest place is in a basement, storm shelter, or a solidly fixed object like a bathtub (put a mattress over top to protect against debris), if no underground cover is available.

The Facts:

1.) Tornadoes can form at any time of the year, and at any time of the day. Big myth that tornadoes don't strike during the evening or late at night!

2.) Tornadoes are more frequent between 3:00pm, and 9:00pm, due to cold and warm air rising, this is typical high time for storm chasers.

3.) Tornadoes always have signs of forming. Actually one out of five tornadoes strike with little or no warning at all, other than weather watches, and warnings that tornadoes are imminent.

4.) Tornadoes are almost always attached or apart of a thunderstorm system. Most systems due to the severe colder air mass produce large size chunks of hail.

5.) In the United States there are over 1200 tornado touchdowns every single year, and the numbers are still growing.

The warning signs:

1.) Dark ominous skies that have an almost greenish hue or tinting.

2.) A tornado can sometimes cause a distinctive roar or growling that can be as loud as an oncoming freight train.

3.) Trees begin to bend in many different directions during a severer thunderstorm.

4.) The formation of a wall cloud can be an indicator of a tornado, and it may appear as though the cloud bank drops off at steep edge.

5.) Debris: If you see a cow, car or other large flying projectiles just outside your window, a tornado is quite likely about to visit.

6.) Extremely fast moving storm systems. One minute it appears relatively calm, the next a large storm surges inward, clouds appear to be moving quickly across the sky.

The real unfortunate truth about dealing with a tornado is it can have odds equal to that of a game of bingo, since nothing is certain until your number is called. A tornado can tear apart a home only a few doors down, and leave another house completely untouched. Some of the most amazing stories involve children who have been sucked up into the funnel, and have been safely deposited with not even a scratch to show for it. The only way to protect yourself is to get as far below ground level as humanly possible, or as low to the ground as you can. If driving quickly pullover and find a culvert or low lying ditch and hope that nothing happens.

So you now either have greater respect for those that live in the legendary Tornado Alley, or you have just changed your plans to move there. I try to be as blunt as possible when I describe a tornado, since I have had the unfortunate insight due to my own up close and personal experience. Luckily this was a mild category F2, and I was able to live to see another day, but it still struck the fear of God in me at the time! Like I said before, there is no running or hiding like in the movies, because when a "finger of God" points at you; only random fate will determine if you survive a tornado!

More about this author: Douglas Black

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