Thunder is one of nature’s most dramatic sounds, often accompanying the brilliant flash of lightning during a storm. But what causes this rumbling roar in the sky?

Mammatus cloud: A drooping cumulonimbus cloud in its latter stage of development (has a pouch-like appearance). These clouds are often are seen hanging from the anvil of a severe thunderstorm, but ...

From towering cumulonimbus clouds that signal severe thunderstorms to the eerie, pouch-like mammatus clouds often associated with turbulent weather, each cloud formation carries unique information.

When associated with cumulonimbus clouds, they can often indicate strong storms. However, they can also take place with other types of clouds, too, even when the weather is fairly calm.

Cumulonimbus clouds are associated with thunderstorms. If the conditions are right, these storms could produce severe weather. Comparatively, stratus clouds are known for their flat appearance.

“Once it gets up there around 36,000 feet it kind of hits a ceiling, and it just starts spreading out, and since the winds are so light, the clouds are going in all directions, a circular pattern,” ...

“Once it gets up there around 36,000 feet it kind of hits a ceiling, and it just starts spreading out, and since the winds are so light, the clouds are going in all directions, a circular pattern,” ...