Clouds can be huge billowing puffs that look like cotton balls above us, or clouds can be thin, transparent wisps that resemble feathers in a big blue sky. If you looking up at the sky are paying attention to the clouds, you’ve probably noticed they come in all shapes and sizes. There is no difference between fog and clouds other than altitude. Fog is defined as visible moisture that begins at a height lower than 50 feet. If the visible moisture begins at or above 50 feet, it is called a cloud.
Learning about each type of cloud is fun. If you learn a little about each type of cloud, you might get pretty accurate at predicting the weather.
Have you ever wondered how clouds form and why some look different than others?
Clouds form due to surface heating, from mountains, when air is forced to rise and from weather fronts. Scientists have organized clouds into ten broad categories. Cloud altitude levels, temperature, wind, and other conditions determine what type of cloud will form. To help you identify the different types of clouds, there are four qualities you can use that all clouds have.
Height: Where in the sky the cloud typically occurs (low-level, mid-level, or high-level)
Color: The color of the cloud
Shape: The form the cloud typically takes
Weather: The weather the cloud is usually associated with or predicts
To make it easier for you to identify the top ten clouds next time you look up to the sky, here is a list of cloud types and their properties.
Shape: Heap-like, often grouped together
Description: Altocumulus clouds are fairly common clouds that look like round white or gray patches in the sky. They are sometimes grouped in parallel lines and have been described as looking similar to tufts of wool or fish scales.
Color: White or light gray
Shape: Thick and flat
Weather: Usually indicates warm weather approaching, may cause light rain
These clouds form a white or gray layer that blankets the sky at mid-level. There are usually no patches of blue sky when these clouds appear, but the sun is often visible as a dimly lit disk behind the clouds (although no shadows appear on the ground).
Color: White or gray
Shape: Rows of small patchy clouds
Weather: Usually sunny and cold
Cirrocumulus clouds are much smaller than most other types of clouds, and they are sometimes called cloudlets. They are found at high altitudes and are made of ice crystals. They often are arranged in parallel rows. They are one of the rarer types of clouds and usually don’t last long.
Color: Transparent or whitish
Shape: Wispy, but thicker than cirrus clouds
These are transparent, wispy clouds that cover most or all of the sky. The best identifier for cirrostratus clouds is a halo or ring of light surrounding the sun or moon.
Shape: Wispy or feathery
Weather: Warm front may be approaching
Wispy clouds located high in the atmosphere are likely cirrus clouds. They are thin and white with lots of blue sky visible. They can occur in fair weather or when a warm front or large storm is approaching.
Height: Low-level, but can spaln all layers
Color: Pale to dark gray
Shape: Dense and towering
Cumulonimbus are the classic “thunderstorm clouds” and are large towering clouds that are often dark in color. Seeing them is a sign that a storm is likely on its way. They can be very large, appearing like a mountain (sometimes with a flat top).
Shape: Fluffy, tall; looks like cauliflower
Weather: Typically sunny
The stereotypical puffy cloud you probably drew a lot of when you were a kid, cumulus clouds are dense individual clouds that are bright white on top and gray underneath. They typically appear earlier in the day when it’s sunny.
Color: Dark gray
Shape: Large thick layer
Weather: Steady rain or snow
Nimbostratus clouds form a thick, dark layer across the sky. They are often thick enough to blot out the sun. Like cumulonimbus clouds, they are associated with heavy precipitation, but, unlike cumulonimbus, you can’t pick out individual nimbostratus clouds.
Weather: Appear before or after a storm front
Stratocumulus clouds are somewhat similar to cumulus clouds but are flatter, thicker, and darker. There is less blue sky between the clouds, and the weather will appear more cloudy than sunny.
Color: Gray or white
Shape: Featureless flat layer
Weather: Gloomy weather, sometimes with light precipitation
Similar to fog (but on the horizon instead of on the ground), stratus clouds are a gray featureless layer of clouds that cover all or most of the sky.
With so many different kinds of clouds, not all fit into the top ten. There are others that occur with specific circumstances. We have a few of them listed out because they are so unique. Mammatus clouds are actually altocumulus, cirrus, cumulonimbus, or other types of clouds that have these pouch-like shapes hanging out of the bottom. Orographic clouds get their shape from mountains or hills that force the air to move over or around them. Lenticular clouds are shaped like a lens or flying saucers! They may get their shape from hilly terrain (another type of orographic cloud) or just the way the air is rising over flat terrain. The Kelvin Helmholtz formation looks like rolling (undulating) waves and is called the Kelvin-Helmholtz cloud, named for the physicist who first studied its flowing formation.