Thunderbolt is more in heat and humid weather. When hot air cools rapidly, thunderstorms are formed. In this thunderstorm, the speed of the air is triggered. As a result, the air's water vapor turns into rain, dew point and snowflake at the same time. Because of the mutual conflict of snow and snow, the ice's electron charge shocks the ice. 
This creates fixed electrical charges. This charge accumulates and produces severe thunderstorms. When the electric spark creates high temperature, intense sound is formed. Lightning flowing through the air generates about 30 thousand degrees centigrade temperature. As a result, the wind is rapidly expanded and acute sound is formed. (A) In the cloud of own + and - charge (it is called intra cloud or, IC discharge) (b) A cloud + or - with other clouds in charge - or + with charge (it is called cloud to cloud or, CC discharging) (C) Cloud with charge + (it is called cloud to ground or, CG discharging) + At the time of discharge + from charge - electricity flows through the air in the form of spark. This is the thunderstorm. The literal meaning of thunderbolt is "The electricity in the earth is falling". However, the lightning or charge does not fall on the ground in all lightning. Electric charge only falls in the ground due to lightning produced by CG discharging.