Tornadoes are violently rotating columns of air that extend between clouds and the ground. They can form when warm, moist air meets cold air, creating thunderstorms with the potential to produce tornadoes. Tornado strength is measured using the Enhanced Fujita Scale from EF0 to EF5 based on wind speed and damage caused. Tornado Alley in the central United States experiences most tornadoes during spring and summer. When a tornado watch is issued, tornadoes may form, while a warning means a tornado has been sighted and people should take shelter immediately.

1. Tornadoes

2. What is a Tornado? “ A tornado is a violently rotating column of air extending between, and in contact with, a cloud and the surface of the earth.” http://www.weather.com/ready/tornado/index.html

3. How do they form? Warm, moist air that meets cold air and dry air can create thunderstorms which have the possibility of producing tornadoes. The exact way tornadoes are formed are unknown. http://www.spc.noaa.gov/faq/tornado/

4. How strong are they? Tornadoes are measured in strength by the Enhanced Fujita Scale. Damage helps estimate the wind speeds of the tornado. http://en.wikipedia.org/wiki/Enhanced_Fujita_Scale

5. Enhanced Fujita Scale http://en.wikipedia.org/wiki/Enhanced_Fujita_Scale Scale Wind Speed (MPH) Damage Caused EF0 65-85 Roof lightly damaged, broken tree branches EF1 86-110 Mobile homes turned over and roofs severely damaged EF2 111-135 Roofs torn off and trees uprooted EF3 136-165 Levels of homes destroyed and cars picked up ad thrown EF4 166-200 Houses completely destroyed EF5 >200 Reinforced concrete very damaged

6. Where do they occur? Tornadoes can be formed anywhere in the United States. They mostly are formed during the Spring and Summer months. http://www.ncdc.noaa.gov/oa/climate/severeweather/tornadoes.html#alley

7. Tornado Alley http://www.ncdc.noaa.gov/img/climate/research/tornado/stalley.gif

8. Tornado Watch There is a possibility that a tornado might form; listen for future weather updates. http://www.fema.gov/hazard/tornado/to_terms.shtm

9. Tornado Warning A tornado has been detected visually or on radar. Head to safety. http://www.fema.gov/hazard/tornado/to_terms.shtm

10. Tornado Safety Tips If you see a tornado or hear the tornado siren immediately head to a basement or to the lowest interior room. If you are in a mobile home, vehicle, or outside seek shelter in a building or lay flat in a ditch. http://www.fema.gov/hazard/tornado/to_during.shtm

11. Tornado Video Tornado Video

12. Work Cited Slide 1- <div xmlns:cc=&quot;http://creativecommons.org/ns#&quot; about=&quot;http://www.flickr.com/photos/pingnews/452392668/&quot;><a rel=&quot;cc:attributionURL&quot; href=&quot;http://www.flickr.com/photos/pingnews/&quot;>http://www.flickr.com/photos/pingnews/</a> / <a rel=&quot;license&quot; href=&quot;http://creativecommons.org/licenses/by-sa/2.0/&quot;>CC BY-SA 2.0</a></div> Slide 2- Weather.com The Weather Channel, n.d. Web. 10 Oct. 2009 <http://www.weather.com/ready/tornado/index.html>. Slide 3- Noaa.gov NOAA, n.d. Web. 10 Oct. 2009 <http://www.spc.noaa.gov/faq/tornado/>. Slide 4 and 5- Wikipedia.org N.p., n.d. Web. 10 Oct. 2009 <http://en.wikipedia.org/wiki/Enhanced_Fujita_Scale>. Slide 6- ncdc.noaa.gov NOAA, n.d. Web. 10 Oct. 2009 <http://www.ncdc.noaa.gov/oa/climate/severeweather/tornadoes.html#alley>. Slide 7- Concannon et al. 2000. NOAA. Web. 10 Oct. 2009 <http://www.ncdc.noaa.gov/img/climate/research/tornado/stalley.gif>. Slide 8 & 9- Fema.gov FEMA, 4 June 2009. Web. 10 Oct. 2009 <http://www.fema.gov/hazard/tornado/to_terms.shtm>. Slide 10- Fema.gov FEMA, 4 June 2009. Web. 10 Oct. 2009 <http://www.fema.gov/hazard/tornado/to_during.shtm>.