Look up: Mesocyclone

1. mesocyclone
   (from the article `tornado`) Doppler radars can measure rotation in the updraft and allow forecasters to watch the formation of a mesocyclone (that is, a region of rotating air ... Tornadoes may occur wherever conditions favour the development of strong thunderstorms. Essential conditions for such storms are the presence of ... [2 re...
   Found on http://www.britannica.com/eb/a-z/m/76
   
   
2. Mesocyclone
   A cylinder of cyclonically flowing air that form vertically in a severe thunderstorm. They measure about 3 to 10 kilometers across. About 50% of them spawn tornadoes.
   Found on http://www.physicalgeography.net/physgeo
   
   
3. MESOCYCLONE
   A area of rotation of storm size that may often be found on the southwest part of a supercell. Its circulation can be larger than the tornado that may develop within it, but not necessarily. Originally a radar term for a rotation signature that met certain criteria, it is best seen on Doppler radar.
   Found on http://www.weather.com/glossary/m.html
   
   
4. Mesocyclone
   indicated on Doppler weather radar. A `mesocyclone` is a vortex of air, approximately 2 to 10 miles in diameter (the mesoscale of meteorology), within a convective publisher = American Meteorological Society |author= Glossary of Meteorology |title=Mesocyclone| date= June 2...
   Found on http://en.wikipedia.org/wiki/Mesocyclone