ZIMSEC O Level Geography Notes: Weather Hazards: Lightining
Is typically caused by the physical characteristics of cumulonimbus weather conditions.
As rain drops fall the energy which they have causes a positive charge to develop at the top of a cloud and negative charges to develop at its base.
The earth becomes negatively charged.
Lightning, which simply flashes of electricity, moves from the top of the cloud to the bottom of the cloud and from.
It also occurs from the bottom of the cloud to the ground.
Also as water droplets and ice crystals in clouds fall and collide with one another, especially in super-cooled water vapor, they form like charges from which flashes of electricity move from part/cloud to another part/cloud with a different charge.
Due to the last process outlined above most lightning flashes occur within and between clouds.