Tornadoes


A tornado is a violently rotating column of air that is in contact with the ground. Tornadoes form from thunderstorms. Rising air within the thunderstorms updraft tilts the rotating air from horizontal to vertical.An area of rotation, 2-6 miles wide, now extends through much of the storm. Most strong and violent tornadoes form within this area of strong rotation. A lower cloud base identifies an area of rotation known as a rotating wall cloud.Moments later a strong tornado develops in this area. Softball-size hail and damaging "straight-line" winds also occurred with this storm. This area is often nearly rain-free. Tornadoes can be detected before or when they occur by using the Pulse-Doppler radar. Tornadoes can cause much damage and can even drive straw into trees. There is a scale that is used to classify tornadoes. This scale starts at F0 and goes to F5 with F5 being the greatest.
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Funnel Cloud


A funnel cloud is a funnel-shaped cloud that is made up of water droplets. Most tornadoes form with a funnel cloud that turns into a tornado. When the funnel cloud touches the ground it becomes a tornado. A funnel cloud can be seen in the shape of a cone. A funnel cloud doesn't need to touch the ground to form a tornado.A debris cloud underneath a thunderstorm is all that needs to be seen to know that a tornado is present. A funnel cloud is quite noticeable as it passes overhead. A pressure drop is often noticeable as well, in the form of popping ears in anyone below the funnel cloud. Even if there is no tornado coming from a funnel cloud, still seek shelter because there could be a tornado forming.

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Waterspout Tornado




A waterspout tornado is a tornado that occurs over the surface of the water. Waterspouts do not suck up water but the water is in the tornado is from condensation. Waterspouts do not form from salt water over a sea. They form from fresh water condensation.There are five stages in the waterspout tornadoes life cycle. The formation of a dark spot on the water surface, spiral pattern on the water surface, formation of a spray ring, development of the visible condensation funnel, and ultimately decay. Formation of these colored disks on the water, a pattern of light and dark-colored spiral bands develop from the dark spot on the water surface. They form when high layers of cool air blow across a body of water while warm moist air sweeps up from above.They spin up as they move up the surface boundary from the horizontal shear near the surface, and then stretch upwards to the cloud once the low level shear vortex aligns with a developing thunderstorm.Water twisters can move from 2 to 80 miles an hour. The winds inside a waterspout can be from 60-120 mph. Similar to regular tornadoes, they can be seen with more than one.
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Supercell Tornadoes




A Supercell is a long-lived thunderstorm possessing a rotating up draft.
Tornadoes tend to stay on the ground for long periods of time. Superc-
ell tornadoes are formed after a Supercell thunderstorm has occurred.
Less than half of Supercell thunderstorms produce a Supercell tornado.
They can occur anywhere in the world if the weather conditions
are right.Supercells occur the least and are the severest.Supercells are
classified into two groups: Low precipitation(LP)and high precipitation(HP).
LP Supercells are found in climates such as the high plains. HP
Supercells are found in moist areas. Supercells are most common in the
Great Plains.Most have winds above 200 mph.Supercells cause the
most damage out of any tornadoes.














Fire Whirl


A fire whirl, (fire devil or fire tornado) is a rarely captured tornado in which a fire, under certain air conditions and currents), acquires a vertical form and forms a whirl, that looks like a tornado. Fire whirls may be whirlwinds separated from the flames, either within the burn area or outside it itself. Fire whirls commonly cause a large threat to dry areas. Wind blows the fire whirl to the sides spreading it out. They can spread to form wild fires, damaging a large area.Fire-whirl.jpg

Dust Devils


Dust devils generally form in the early morning or late afternoon in the hot sun. They form over dry land or in a desert area. Mostly harmless dust devils, form when winds blow around dust that rarely reach speeds of 70 mph. They can last from two to five minutes or longer. Dust devils are different from any other tornadoes because they do not form from any cloud.

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Gustnado


A gustnado is a shot lived tornado. They form in from of a thunderstorm appearing much like a Dust Devil. They can have winds reaching from 50 to 60 mph. Gustnados are commonly confused with tornadoes. Gustnados do not form from any other cloud.

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Landspout


A landspout tornado is a less intense compared to a supercell tornado and they do not last very long. Even being such a less intense tornado, it can still cause damages with wind. The condensation funnel of a landspout does not come in touch with the ground. When it does come in touch with the ground, it can form a dust cloud. Landspouts can be compared to waterspout tornadoes.

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http://en.wikipedia.org/wiki/Tornado
http://www.nssl.noaa.gov/edu/safety/tornadoguide.html
http://teacher.scholastic.com/activities/wwatch/tornadoes/
http://www.noaa.gov/tornadoes.html
http://www.weatherwizkids.com/weather-tornado.htm
http://www.fema.gov/hazard/tornado/index.shtm
http://en.wikipedia.org/wiki/Funnel_cloud
http://www.weatherscapes.com/album.php?cat=clouds&subcat=funnel_clouds
http://www.weatherquestions.com/What_is_a_funnel_cloud.htm