Tornado question

[vbhoutex]

I know how tornados form and most of the other definitions and information associated with them, but what makes one tornado form into an EF5 as opposed to an EF2?

[meteorologist]

A better environment for tornado strength creates stronger tornadoes. Wind shear, dry lines, instability, cloud height, low level jet are some of the ingredients. For a more complete answer, see:

http://www.spc.noaa.gov/faq/tornado/

http://www.weatheranswer.com/public/Tor ... tion_4.pdf

http://www.weatheranswer.com/public/Thunderstorm.pdf

http://www.weatheranswer.com/public/Tor ... tion_3.pdf