Clouds are formed when water vapor evaporating from the surface of the Earth condenses around microscopic particles in the atmosphere. When warm air meets colder air, this triggers the condensation process. This simply means that instead of vapor, the water or, in some cases ice, becomes solid. There are many different types of clouds, each with their own unique look and effects.
Clouds receive their classifications based on appearance as well as where they form in the atmosphere. One that many are all too familiar with is the cumulonimbus. To break down the name, “cumulo” indicates a puffy, piled up cloud and “nimbus” identifies this cloud as capable of producing precipitation. All cumulus clouds are classified as vertical clouds. These are the clouds one sees in advance of a rain or snowstorm, looking quite heavy and full as the storm grows near. These are clouds which can produce thunder and lightning, which is why they are nicknamed thunderheads. They are also capable of some of the more extreme weather you sometimes witness such as strong winds, hail and tornadoes. Compare these to a cumulus cloud which, while puffy and piled, floats harmlessly overhead. They are often at a much lower altitude than the cumulonimbus.
Cirrus clouds are high-altitude clouds that most people have likely seen. They take their name from a Latin word meaning wisp of hair. Again, this is an exceptionally accurate description. These clouds are thin and wispy, riding high in the atmosphere. Generally, they are composed of ice crystals, rather than water droplets.
Next you have stratus clouds, which occupy lower altitudes. They are so named because of their layers or strata. They are best described as flat, uniform clouds. Nimbostratus clouds are also capable of producing precipitation, but nothing as extreme as the cumulonimbus. Did you know that fog is also a cloud formation? Fog refers to very low-lying or ground-hugging stratus clouds. Here you can see the condensation process up close because it’s all around you. It makes you feel damp because it is composed of water droplets.
There are more clouds than are referenced here, as each of these broad classifications encompasses many different types. There are even certain clouds that appear after tornadoes, called mammatus clouds. These are so named because they look very much like teats or breasts. Other clouds are more likely to be seen over mountains, such as orographic and pileus clouds. No matter where you find them, clouds can be an interesting object for study in the fascinating world of weather.