What causes tornadoes?

What causes landfalling hurricanes to spawn tornadoes east of their track?

• The purpose of this question is is for me to fully understand how tornadoes are spawned to the east of the landfalling hurricane's track. Why does this happen and what are the factors that behind their formation?

• Answer:

  It is not necessarily confined to the east of the track, but anyway hurricanes can be prolific tornado spawners particularly in their outer rainbands well away from the center. This is because this area tends to have greater instability and the wind structure around the hurricane is such that low level wind shear (winds changing in speed and direction as altitude increases) is typically fairly large as well. Closer to the center those conditions are not as well pronounced.