tornadoes n.
Skip this Video
Loading SlideShow in 5 Seconds..
Tornadoes PowerPoint Presentation
Download Presentation

Loading in 2 Seconds...

play fullscreen
1 / 7

Tornadoes - PowerPoint PPT Presentation

  • Uploaded on

Tornadoes. Jauris llaverias-607. What are tornadoes.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'Tornadoes' - bing

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript


Jauris llaverias-607

what are tornadoes
What are tornadoes
  • WHAT ARE TORNADOES A tornado is basicaly a violently rotating colum of air extanding form a thunderstorm to the gorundlevels.Some of the most violent tornadoes are capable of tremendous destrucation due to thier incredibly fast wind speeds of 250 mph or more. Damage paths caused by a tornado can be about one mile wide 50 miles long!
  • Tornadoes are powerfully twisting columns of air that make contact with the ground. They form from large storms and hit the ground creating an explosion of dust and wreckage on the ground. In general, tornadoes are about 500 feet wide, less than 1,000 feet long, and less than 112 miles per hour. However, very strong winds may produce a MILE wide tornado, and may travel up to 300 miles per hour! Some may even last more than an hour and cause severe damage. You may know a tornado is coming if the sky turns a greenish-black colour, debris is falling from the sky, and a funnel-shaped cloud forms. It may even start hailing before a tornado. The best thing to do is seek shelter as soon as possible so you are safe from the storm.
  • How Do Tornadoes Form?
  • Tornadoes are associated with large (supercell) thunderstorms that often grow to over 40,000 feet. A column of warm humid air will begin to rise very quickly.
  • 1. Air Rotates Because of Wind Shear. How the column of air begins to rotate is not completely understood by scientists, but one way the rotation appears to happen is when winds at two different altitudes blow at two different speeds creating wind shear. For example, a wind at 1000 feet above the surface might blow at 5mph and a wind at 5000 feet might blow at 25mph. This causes a horizontal rotating column of air.
  • 2. Faster Spin Makes a Funnel Cloud. If this column gets caught in a supercell updraft, the updraft tightens the spin and it speeds up (much like a skater's spins faster when arms are pulled close to the body. A funnel cloud is created.
  • 3. The Funnel Rotates and Touches Down. The rain and hail in the thunderstorm cause the funnel to touch down creating a tornado.
what causes tornadoes
What causes tornadoes
  • What causes tornadoes?
  • Tornadoes form in unusually violent thunderstorms when there is sufficient (1) instability and (2) wind shear present in the lower atmosphere. Instability refers to unusually warm and humid conditions in the lower atmosphere, and possibly cooler than usual conditions in the upper atmosphere. Wind shear in this case refers to the wind direction changing, and the wind speed increasing, with height. An example would be a southerly wind of 15 mph at the surface, changing to a southwesterly or westerly wind of 50 mph at 5,000 feet altitude. This kind of wind shear and instability usually exists only ahead of a cold front and low pressure system. The intense spinning of a tornado is partly the result of the updrafts and downdrafts in the thunderstorm (caused by the unstable air) interacting with the wind shear, causing a tilting of the wind shear to form an upright tornado vortex. Helping the process along, cyclonically flowing air around the cyclone, already slowly spinning in a counter-clockwise direction (in the Northern Hemisphere), converges inward toward the thunderstorm, causing it to spin faster. This is the same process that causes an ice skater to spin faster when she pulls her arms in toward her body. Other processes can enhance the chances for tornado formation. For instance, dry air in the middle atmosphere can be rapidly cooled by rain in the thunderstorm, strengthening the downdrafts that are needed for tornado formation. Notice that in virtually every picture you see of a tornado the tornado has formed on the boundary between dark clouds (the storm updraft region) and bright clouds (the storm downdraft region), evidence of the importance of updrafts and downdrafts to tornado formation. Also, an isolated strong thunderstorm just ahead of a squall line that then merges with the squall line often becomes tornadic; isolated storms are more likely to form tornadoes than squall lines, since an isolated storm can form a more symmetric flow pattern around it, and the isolated storm also has less competition for the unstable air which fuels the storm than if it were part of a solid line (squall line) of storms. Because both instability and wind shear are necessary for tornado formation, sometimes weak tornadoes can occur when the wind shear conditions are strong, but the atmosphere is not very unstable. For instance, this sometimes happens in California in the winter when a strong low pressure system comes ashore. Similarly, weak tornadoes can occur when the airmass is very unstable, but has little wind shear. For instance, Florida -- which reports more tornadoes than any other state in the U.S. -- has many weaker tornadoes of this variety. Of course, the most violent tornadoes occur when both strong instability and strong wind shear are present, which in the U.S. occurs in the middle part of the country during the spring, and to a lesser extent during fall.
  • Tornadoes occur when horizontally rolling air masses are turned vertical by thunderstorm updrafts. The resulting rotating updrafts called mesocyclones can the tighten and intensify to produce tornadoes.
the effects of tornadoes
The effects of tornadoes
  • The effects of tornadoes can be deadly and crazed they effect all of us because if they effect one of us they effect all of us because they can lead to some type of disruption in the business plus tornadoes pick up trees and houses and swing them around which can kill so many people because thousands and thousands of people are dying because of these home and thousands thousand
  • of people are living in the street because of this catstrophy that has happened
how to prepare for tornadoes
  • Make sure to look out for the forecast
  • Always have an emergency plan
  • Always be ready for anything
  • Make sure to locate a place that is safe for you to stay
  • Be sure to always have emergency kit
  • Always expect what you would never think that would happen
  • And always stay safe
fun facts
Fun facts
  • Fun Tornado Facts
  • Welcome to the Tornado Facts website. Here you will find many interesting facts on tornadoes and twisters. Here are some fun tornado facts:
  • The most powerful Tornadoes occur in the United States.
  • A typical tornado only lasts for a few minutes.
  • Every tornado has its own color, sound and shape.
  • You need to step on the pedal of a car pass 70 miles per hour to outrun the fastest tornadoes.
  • The chances that a tornado is a F5, the highest classification for a tornado on the F-scale, is less than 0.1%
  • Tornadoes have been reported in every state in the US and also in every season.
  • A Tornado can occur at any time, but most often between 3pm and 9pm.