How does a tornado or hurricane or something like that start?
A tornado forms from the twisting of rising air. Radar and storm spotters are two primary sources that tornadoes are identified. The troposphere needs to have instability for a thunderstorm and a tornado to occur. Instability release produces the updraft of a thunderstorm. The closer the base of the updraft (known as Level of Free Convection) is to the surface then the better it is for tornadoes. The base of the updraft will tend to be closer to the surface when the dewpoints and relative humidity in the lower troposphere are higher.
