Tornado Formation: Supercell Thunderstorms

• air-mass thunderstorms don’t form tornadoes

  • not big enough and don’t have enough energy

• most tornadoes are produced within supercell thunderstorms

  • huge updraft of air causes wind shear and tilts the thunderstorm

  • tilt allows warm air to rise into central portions of the storm, while rain and hail fall in the front

  • cold air (containing rain and hail) doesn’t extinguish the storm like in an air-mass thunderstorm

  • storm moves laterally

• most tornadoes are produced by supercell thunderstorms

• 30% of supercell thunderstorms produce tornadoes

How Strong Are Tornadoes?

• very high speed winds

  • up to 310 mph

• blow away buildings and tress

• thrown debris acts like bullets or shrapnel

  • break windows, kill people

• fast winds can blow away roofs, then exposed walls are easily blown over

Storm Movement

• in the Northern Hemisphere, tornadoes and thunderstorms tend to move northeast due to prevailing winds

• the most tornadoes happen in Oklahoma