The process of how clouds form begins with air containing water vapor, which is water in its gaseous form. The air is forced to rise, either by warm air rising (like a hot air balloon) or by moving up a mountain side to higher elevations. As the air rises, it cools. Water vapor condenses and latches onto tiny pieces of dust called condensation nuclei. These small particles can be any number of things: salt from the ocean, dust carried by the wind from dry land or even particles created by air pollution. Essentially, clouds are made up of water drops or ice crystals floating in the sky.
When the water vapor condenses it forms a cloud. The type of cloud that forms, depends on how high the cloud base is and what temperature the air was when it formed. If the cloud base is low and the air was warm when it formed, you’ll see towering cumulus clouds like those on a summer day, forming as heating from the sun warms the ground and creates updrafts of warm air. If the cloud base is high and cold, you’ll see cirrus clouds: wispy streams of ice crystals that form as water vapor freezes directly into ice without ever becoming a liquid. In between these extremes are all kinds of different clouds: stratus clouds that blanket an entire sky in a layer; nimbostratus clouds that bring rain.
”Clouds are the sky’s imagination.”– Terri Guillemets
Water follows a cycle. It evaporates and collects in clouds and then falls as rain or snow. In general, most of the water will fall back down to earth, where it can evaporate again. Some of the water from the rain falls into streams, rivers, or lakes and flows eventually to the ocean. In this way, water is recycled over and over again on earth.
The biggest factors affecting cloud cover are temperature and moisture in the atmosphere. When both of those increase, cloud cover increases; when they decrease, cloud cover decreases. However, there are also many other factors that influence how much it rains or snows, like wind speed and direction. These factors have a lot to do with the size and shape of clouds.
Types of Precipitation
Obviously, rain is the most common type of precipitation. Very small drops are considered drizzle. When the drops reach the size of about 0.5 mm or bigger it is considered rain. There are several types of ice that falls from the sky; small ice pellets are considered sleet and of course bigger ones are hail, which can get really big and hazardous to your health at times. And of course, there is snow, which technically can take several distinct forms from flakes to pellets.
Weather Fronts and How Clouds Form
Clouds can be formed when two large air masses collide. Warm fronts produce clouds when warm air slides over cold air. A number of different types of clouds form in this way; altocumulus, altostratus, cirrocumulus, cirrostratus, cirrus, cumulonimbus, nimbostratus, stratus, and stratocumulus.
Cold fronts form clouds when heavy cold air slides under lighter warmer air pushing it upward. Cumulus clouds are formed in this way. But they often grow into cumulonimbus clouds, which produce thunderstorms.
Consider this an introduction to how clouds form. There is much more that can be learned. But unless you intend to become a meteorologist, this might be enough!
Retired from the real world after several careers. But thinking back, college was a lot of fun. And researching various topics for debate team was one of my favorite things to do. On this little website I get to research anything that catches my attention. How fun is that! Add in a little commentary and opinion for good measure. And that’s it!