Lightning is an atmospheric discharge of electricity accompanied by thunder, which typically occurs during thunderstorms.The bolt of lightning can travel at speeds of 60,000 m/s (130,000 mph), and can reach temperatures approaching 30,000 °C (54,000 °F).
How lightning initially forms is still a matter of debate. Ice inside a cloud is thought to be a key element in lightning development, and may cause a forcible separation of positive and negative charges within the cloud, thus assisting in the formation of lightning.
The study or science of lightning is called fulminology, and someone who studies lightning is referred to as a fulminologist. (Source: Wikipedia)
The photos of these albums are taken during the Nor wester in Calcutta (Kolkata).