 Ah, clouds. So sweet and puffy. So dark and scary. Whoa! Sorry, where was I? Right! Clouds! Clouds are made of water droplets or ice crystals that are so small and light they stay afloat in the air. But how does the water and ice get into the sky? And how do they form a cloud? Clouds form when water from oceans, lakes and rivers evaporates, becoming water vapor. Warm air containing water vapor rises. If it rises high in the atmosphere, the air cools down, and some of the water vapor condenses into liquid water. The condensation process is easier when the droplets have a particle to condense upon. Oh, hey there! These particles, like dust or pollen, are called condensation nuclei. When enough water vapor condenses upon many condensation nuclei, that forms a cloud. Clouds can form in many places where air is rising, at weather fronts, where air is heated at the Earth's surface, where air is forced to rise in areas of low pressure, or when wind encounters a mountain range and has nowhere to go, what up? Hello! As you can see, there's a lot more to clouds than meets the eye.