Lightning is a huge electric spark that jumps between clouds or toward the ground.

The longer version

Inside a storm cloud, collisions between ice crystals and soft hail separate electric charge, leaving one region positive and another negative. When the difference grows large enough, the air breaks down as an insulator, a conducting channel forms, and the stored energy is released in a fraction of a second.

That discharge is what we see as a flash. It may jump between oppositely charged parts of the cloud, between two clouds, or down toward the ground. The channel suddenly heats the surrounding air, and the violent expansion that follows produces the shock wave we hear.

Where this entry sits

Clouds, wind, rain, and storms shape daily life in ways that most people barely notice. This collection explains snow, lightning, rainbows, the turning seasons, temperature, the instruments forecasters rely on, and scraps of old weather lore. The full list sits on the Weather and Climate page, where every entry is listed in order.