What would you do during a Tornado?

Wednesday, May 25, 2011

What Exactly Is A Shelf Cloud?

         A shelf cloud is a low horizontal cloud that form as moist air rises along the front edge of a gust front. Shelf clouds are mostly known to come with severe thunderstorms, and they are common when a thunderstorm has an area near it's base where the air is very stable. The shelf clouds are the outflows of cold fronts and cool sea breezes.
A shelf cloud is a low, horizontal wedge-shaped arcus cloud. Unlike a roll cloud, a shelf cloud is attached to the base of the parent cloud (usually a thunderstorm). Rising cloud motion often can be seen in the leading part of the shelf cloud, while the underside often appears wind-torn. Cool, sinking air from a storms "downdraft" spreads out across the surface with the leading edge called a gust front. This outflow undercuts warm air being drawn into the storm's.
        As the cool air lifts the warm moist air, water condenses creating a cloud which often rolls with the different winds above and below. Occasionally people seeing a shelf cloud may believe they have seen a wall cloud, which is common in tornadoes. This is a common mistake, since an approaching shelf cloud appears to form a wall made of cloud. A shelf cloud appears on the leading edge of a storm, and a wall cloud will usually be at the rear of the storm. A sharp, strong gust front will cause the lowest part of the leading edge of an shelf cloud to be ragged and lined with rising fractus clouds. In a severe case along the edge of twisting masses of irregular shaped clouds that may reach to the ground or be accompanied by rising dust. A very low shelf cloud accompanied by these signs is the best indicator that a potentially violent wind is approaching. An extreme example of this phenomenon looks almost like a tornado and is known as a gustnado.

Tuesday, May 24, 2011

What Are The Different Types of Tornadoes?

        Let's state the types of tornadoes to start with: a supercell torando, a landspout, a gustnado, a waterspout, and dust devils. Now that you know the types maybe we should dig a little deeper and figure out what these tornadoes are like. First we can start on the supercell tornadoes. Supercell tornadoes are formed from continuous thunderstorms that have a consistent rotating updraft of air. Supercell tornadoes are most commonly known to have a wedge-like shape that makes the tornado look very large. A supercell thunderstorm has a low-hanging rotating cloud called a "wall cloud". The wall clouds have a dangerous looking shape that really just hangs over an area. Wall clouds will sometimes have areas that will pour rain while the other areas don't have rain at all. Wall clouds overall are just really unpredictable because they might just produce a supercell tornado. Supercell tornadoes are the most violent tornadoes because they have the longest touchdown period( maybe and hour or more) and the have the most frightening wind speeds that reach higher than 200 mph.
         A landspout tornado  is generally weaker than a supercell tornado, a landspout does not form with a wall cloud. It may be be seen beneath towering clouds and is the land version of a waterspout. It often forms along the leading edge of the rain-cooled downdraft air coming from a thunderstorm, known as a “gust front."
         A gustnado is usually weak and mostly short-lived. A gustnado usually forms along the "gust front" of a thunderstorm and looks more like a dust whirl or a debris cloud. In these tornadoes it may not appear to be twirling or twisting in any form. These appear like dust devils, just out of the blue.
           A waterspout is a different type of tornado. Even though most people think that it is impossible for tornadoes to form over water I am here to tell you that it is very possible. A few form from supercell thunderstorms, but many form from weak thunderstorms or rapidly growing cumulus clouds. Waterspouts are usually less intense and causes far less damage. They are no more than fifty yards wide, they forms over warm tropical ocean waters, its funnel is made of freshwater droplets condensed from water vapor- not saltwater from the ocean. Waterspouts usually dissipate upon reaching land.
           The last type of tornado we will talk about is called a dust devil. Dry, hot days can bring about a dust devil. Dust devils form because a light breaaze keeps building and causes a swirling pattern. Dust devils are not very violent but they are known to cause minor damage, like blowing cars off the rode and getting dust in your eyes. Dust devils are called cousins of the tornado because the swirl but they do not form in storms like tornadoes do.
            
         

Monday, May 23, 2011

How Do Tornadoes Form?

     It is proven that tornadoes form when thunderstorms create warm, wet, muggy air that collides with cold, crisp air from a cold front. When this happens large storms occur that contain large hail, high wind speeds, and on occasion tornadoes.
     During the spring, thunderstorms frequently develop along a "dryline," a dryline separates warm, moist air in the east from hot, dry air in the west. "Tornado thunderstorms" form as the dryline moves east and the two air systems come together.
     The twisting funnel of tornadoes is caused by the change in wind direction, an increase in wind speed, and the two air system rising higher and higher into the atmosphere. This combination of symptoms creates a horizontal spinning effect in the lower atmoshpere. The rising air pushes the horizontal funnel upwards making the funnel vertical. So when the total collisoin between the air systems finally occurs the funnel's rotation is increasing so much in speed that it becomes a full out tornado. 

  This tornado went from Wisconsin to Arkasas and killed two people in Missourri...

Wednesday, May 18, 2011

Terrifying Tornadoes

Here we go, first I want to let you know that the point of this blog is to inform you of how tornadoes are formed. I hope that in describing their formation you don't become more terrified of tornadoes than you probably already are. Second, the purpose of this blog is to show the formation of tornadoes and how they are really created. Third, I really would like to help you achieve a better understanding on what tornadoes are and what they become, etc... Enjoy:)