(WUTR/WFXV/WPNY) – We all know what thunderstorms are, though their stages and formation are quite complex, so let’s break them down. Most thunderstorms form in three stages: the cumulus stage when storm clouds form, the mature stage when the storm is fully formed, and then the dissipating stage when the storm weakens and breaks apart.

The Cumulus Stage

Clouds use warm, moist air as fuel to keep them going and growing. When that warm, moist air moves high up into the atmosphere in an updraft, cumulus clouds form. There are several ways this updraft of warm moist air can form. Sometimes the air is forced up when it hits the side of a mountain. Other times, it’s forced up because of a cold front. 

The Mature Stage

As the cumulus cloud continues to grow, the tiny water droplets within it grow too because as they’re flying up there in the cloud, they’re colliding and sticking to each other. This is when the cloud starts looking dark and gray. Raindrops start to fall through the cloud when the rising air can no longer hold all those water droplets up. Meanwhile, cool dry air flows downward in the cloud (the downdraft), pulling water downward as rain. With an updraft, downdraft, and rain, the cloud is now called a cumulonimbus cloud and the cycling of air up and down is called a thunderstorm cell.

The Dissipating Stage

When the downdrafts in the cloud become stronger, they eventually start cutting off the updraft. This leads to the last stage of a thunderstorm where it weakens and dissipates. The storm dies out with light rain as the cloud disappears from bottom to top. The whole process takes about one hour for an ordinary thunderstorm. Severe thunderstorms like supercells and squall lines are much larger, more powerful, and last for several hours.