The problem of warning and sheltering mobile home residents has become the biggest obstacle to continuing to reduce death tolls from tornadoes. Do wider tornadoes cause more damage? There is a statistical trend toward wide tornadoes having higher EF-scale damage. This can be because of stronger winds or because of greater opportunity for targets to be damaged, or a combination of both.
However, the size or shape of any particular tornado does not say anything conclusive about its strength. Some small tornadoes can still do very violent damage of EF4 or EF5. And, some very large tornadoes over a quarter-mile wide have produced only weak damage.
What is the difference between a tornado and a cyclone? A tornado is a small-scale cyclonic circulation, and in the past, has been referred to as a cyclone. The term cyclone was used to describe anything that rotated counterclockwise, so often tornado a small-scale cyclonic circulation and cyclone were interchangeable. However, people still use it both ways. What is a gustnado? A gustnado is a small and usually weak whirlwind which forms as an eddy in thunderstorm outflows.
They do not connect with any cloud-base rotation and are not tornadoes, but because gustnadoes often have a spinning dust cloud at ground level, they are sometimes wrongly reported as tornadoes.
Gustnadoes can do minor damage e. Are there electromagnetic or magnetohydrodynamic explanations for the development of tornadoes? As far as scientists understand, tornadoes are formed and sustained by a purely thermodynamic process.
As a result, their research efforts are towards that end. They have spent a lot of time modeling the formation of a tornado and measuring many parameters in and around a tornado when it is forming and going through its life cycle.
They have not seen any evidence to support magnetism or electricity playing a role. Can my TV signal detect tornadoes? The idea was to be able to use your TV as a lightning detector to detect the radio waves emitted by a lightning flash, with the assumption that tornadic thunderstorms were very active lightning producers.
But, not all tornadic storms produce large amounts of lightning. Also, TVs are all different and have different sensitivities, and some are even made to filter out lightning signals. Plus, if you are connected to cable, it won't work. The method was found to be completely unreliable and it has mostly been abandoned.
Do tornadoes occur when it is cold? There is no particular temperature at which tornadoes form. It is more about what the surface temperature is in relation to the temperature higher up in the atmosphere.
Even if it is cold near the surface, as long as it is colder higher up, the winds are right to set up low-level wind shear, along with other necessary ingredients, a tornado is possible.
What direction do tornadoes spin? More tornadoes in the Northern Hemisphere spin counterclockwise than clockwise.
Do rocks, hills, or trees increase or decrease the wind speeds in a tornado? Unfortunately, there is no clear answer. How can trees increase the wind speeds? Well, the strongest winds in a tornado occur when air from outside the tornado can flow closest to the center of the vortex.
The conservation of angular momentum, e. So occasionally we see in tornado videos the vortex increasing in intensity when it travels from one type of ground surface say a field into a grove of trees or a housing subdivision. It does not always happen, but often enough that we are aware of it. Here is a look at how your day is shaping up in Raleigh.
It'll mainly stay dry, but a few showers are possible this afternoon. More rain arrives overnight tonight. Snow lovers take note! The higher elevations of the NC mountains may see a little snow early next week. In West Virginia it will be several inches. It's a chilly start to the day, but it'll warm up quickly again today. Clouds move in through the day leading to a few showers by the evening.
More rain is likely after midnight tonight through early Friday More rain is likely after midnight tonight through early Friday morning. On TV we'll show you when to expect some rain and how long these showers will stick around for your On TV we'll show you when to expect some rain and how long these showers will stick around for your Friday morning commute.
Did you see it? Fireball lights up Carolina skies. Video of the SpaceX launch faint, moving left and fireball bright from David Spector tonight. The weather icons don't tell the whole story with the cold front that is on the way. Here's a little preview of what we expect Friday morning. It's much needed rain for some. See you at 11PM! It's another beautiful but toasty November day.
The most violent tornadoes are capable of tremendous destruction with wind speeds of up to mph. They can destroy large buildings, uproot trees and hurl vehicles hundreds of yards.
They can also drive straw into trees. Damage paths can be in excess of one mile wide to 50 miles long. In an average year, tornadoes are reported nationwide. How do tornadoes form? Most tornadoes form from thunderstorms. Myths are full of fantastic and destructive creatures. If it's not a city-leveling angel, then it's giants sauntering vengefully into unsuspecting towns. In reality, all the calamities we're liable to encounter are due to natural phenomena and human will.
But of all the destructive powers in our world, none resembles the ferocity and form of those mythic monsters quite like tornadoes. These storms descend like a dagger from the clouds. They tower over the tallest buildings like titans. And when they lash out at their surroundings, they often seem to act with malicious, mindful intent.
The United States alone experiences more than 1, tornadoes a year, and the storms have been reported on every continent except Antarctica [source: Tarbuck ]. While most storms are weak and occur in sparsely populated areas, tornadoes have been known to hit large metropolitan areas, and they have inflicted heavy casualties on many towns and cities. In , the infamous U. If you've ever watched a whirlpool form in your bathtub or sink while draining the water , then you've witnessed the fundamentals of a tornado at work.
A drain's whirlpool, also known as a vortex , forms because of the downdraft that the drain creates in the body of water. The downward flow of the water into the drain begins to rotate, and as the rotation speeds up, a vortex forms. Why does the water start rotating? There are many explanations, but here's one way to think about it.
Imagine yourself as a particle in the water, suddenly pulled toward the suction that the drain creates. At first, you'd find yourself accelerating toward the drain.
Then, quite literally, there's a twist. Because of your previous momentum and the number of other particles rushing toward the drain at the same time, chances are that you're going to be pushed off to one side of the point of suction when you arrive. That deflection sets you on a spiraling path into the point of suction, like a moth spiraling in toward a light. Once the spiral has started in one direction, it tends to influence all the other particles as they arrive.
A very strong spiraling tendency is created. Eventually, there's enough spiraling energy to create a vortex. Vortices are obviously a common phenomenon. After all, you see them in tubs and sinks all the time. Small dust devils sometimes form when winds flow over hot deserts, and wildfires have been known to produce climbing vortices of flame and ash called fire whirls.
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