Ever notice how most batteries have little plus symbols (+) on their tops and minus symbols (-) on their bottoms? A storm cloud is like a big fluffy battery – the most powerful battery on Earth. Drops of rain and bits of ice blow and fall within the cloud, bumping against one another to create static electricity. Positively charged particles rise to the cloud’s top, while negatively charged particles sink to the lower levels. The difference between the positive and negative particles builds up a current, which arcs through the air as intra-cloud lightning, the most common type of lightning.
The much more dangerous cloud-to-ground lightning works its way downward from the negatively charged lower levels of a cloud (or, in some cases, from the positively charged tippy-top) through a stepped leader, a series of negative charges. The trip down the steps happens faster than the blink of an eye: around 200,000 mph (322,000 kph). Once the stepped leader gets within 150 feet (46 m) or so of the surface, it connects with a positive jolt of electricity that rises through an object on the ground, such as a tree, tower, building, or even you (if you’re silly enough to stand outside during a storm). This upward surge is called a steamer, and it’s the flash of lightning you see with your eyes. When it connects with the leader, it creates a channel to conduct electricity from the earth to the cloud. Zzzzzt! Krakow! Lightning can carry up to a billion volts of electricity – about 50,000 times the current of a typical industrial electrical accident.
Picture Credit : Google