Cumulus — The Puffy Ones
Cumulus clouds are the ones most kids draw — big, puffy, white clouds that look like cotton balls, popcorn, or even castles floating in the sky! The word 'cumulus' means 'heap' or 'pile' in Latin.
Cumulus clouds form when warm air bubbles rise quickly from the ground. They usually have flat bottoms (where condensation starts) and rounded, bumpy tops that grow upward as more warm air pushes them higher.
Fair-weather cumulus clouds are small and scattered across a blue sky. They mean good weather! They usually form in the morning or afternoon when the sun heats the ground, and they disappear in the evening as the air cools.
But cumulus clouds can grow! If the air is very warm and moist, cumulus clouds can build taller and taller, eventually turning into towering cumulus clouds. If they keep growing, they can become thunderstorm clouds (cumulonimbus) — but we will learn about those later.
Cumulus clouds are usually found at low to medium altitudes, about 2,000 to 6,000 feet above the ground.
**Cloud Spotter Tip:** If you see small, scattered cumulus clouds on a sunny day, it is going to be a beautiful day! But if they start growing taller and darker, a storm might be coming.