How are tornadoes predicted?

Forecasters use massive computer programs. Tornadoes form under certain conditions, and if forecasters see those certain conditions, they study the area more. However, these models cannot predict where a tornado will form, only regions where there is the potential for tornadoes. On the scale of individual storms scientists use Doppler radar to detect rotation within a storm. Depending on the signature this can either indicate the mesocyclone that produces a tornado, or the tornado itself.