In storm clouds, tiny particles in the cloud move around
picking up positive or negative energy charges, like when shoes scuff a
rug. The positive charged particles stay light, and rise to the top of
the cloud. The negative charged particles get heavier, and collect at
the bottom of the cloud.
As more particles become charged, they divide into opposing groups in
the cloud. When the power of attraction between them gets too great, the
particles discharge their energy at each other, completing a path for
electricity to travel through the air. We call this flow of electricity
It's the negative charges in the bottom of the cloud that cause
lightning to strike the ground. When the negatively charged particles
group together, they begin to seek out positive charges from the ground
below. The excess electrons create a channel of charged air called a
that reaches down to the ground below. The leaders attract other charged
ground-based channels called streamers.
When the stepped leader from the cloud meets a returning streamer
from the ground, the path is ready. An electrical current called the
stroke, travels back up the path. This return stroke releases
tremendous energy, bright light and thunder.
The typical stroke can last only 30 milliseconds, so four to five
strokes may happen in the blink of an eye. Despite the old saying,
lightning does strike the same place twice.
To review, lightning is created by the attraction between opposite
charges, the same force that creates static electricity. But lightning
uses huge opposite charges to produce an electrical current that's
nothing like what you'd get from static