Oklahoma Tornado May 2013

At least 91 people, including 20 children, are feared dead as a gigantic tornado rips through Oklahoma City suburbs, flattening whole neighbourhoods.
Follow the link for more information.
http://www.bbc.co.uk/news/world-us-canada-22604251

Live reports are from:

http://www.bbc.co.uk/news/world-us-canada-22605586

This time of the year sees the height of the tornado season with the most severe occurring in the above areas.

How do tornadoes form? PDF version of this:
http://downloads.bbc.co.uk/news/nol/shared/spl/hi/sci-nat/06/tornado/pdf/how_tornado_is_formed.pdf

http://news.bbc.co.uk/1/hi/world/5328524.stm  Animated clips