How to Predict the Weather Based on Clouds
Before there were meteorologists, we relied on clouds as a way how to predict the weather. The convenience of the modern age has led many people to forget that it is possible to predict the weather by looking at the clouds though. However, these heaps of moisture that seem to balance in the sky can communicate a lot about what the weather will be like over the few hours or even the next few days if you know how to interpret them. Knowing how to predict the weather, is an especially critical skill for those who spend time deep in the backcountry, where one may not have access to weather reports or radar and getting caught in a storm can be an indeed life or death situation.
Being able to read the clouds do not have to be an esoteric act. Like any skill, interpreting the sky is something that you can learn. Start with essential knowledge, then build upon it until you fully understand what is in the air. The categories of clouds are straightforward actually, beginning what altitude they tend to hang at high in the sky.
The altitude is where a large part of the classifications that organize clouds comes from. After that, the way that a cloud spreads or doesn’t spread matters in terms of what they become in the sky. Your ability to see the sun through it is another factor that matters when you are trying to figure out the type of cloud you are looking at and the weather that it is likely to imply.
Clouds form because warmer evaporated water rises, runs into the particulate matter in the sky, then condenses and cools, forming consolidated ice crystals around those specs of dust. When this condensed moisture becomes thick enough, it falls to the earth again as either snow or rain. The type of clouds formed depends significantly on several other factors though, including air temperature, wind, and the level of available moisture, but knowing all the details of how clouds are formed is not necessary for using them and knowing how to predict the weather. Instead, there are a few basic formations that you can look for, which can tell you a lot about what the weather has in store.
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The Height of a Cloud in the Sky
Before we divide the clouds further into other categories, we can organize them based on the height in the sky and their location. Clouds are either at the high, middle, or low level. The distance from the Earth that each type of cloud is is a primary determining factor for the category within which each kind of cloud falls. However, clouds that form a specific distance from the earth also tend to have a particular characteristic in common.
High-Level Clouds – These are thin clouds found at an altitude between 20,000 and 50,000 feet. Their compact form is a byproduct of the fact that there is little moisture to be found at this level in the sky.
Middle-Level Clouds – Located between 7,000 and 20,000 feet, these clouds are ever changing in their structure. Another distinct feature is that these clouds typically allow the sun or moon to shine through them, although the outline may be faint.
Low-Level Clouds – This category includes any cloud located beneath 7,000 feet. These clouds tend to have flat, dark bottoms and an appearance of being heaped up.
These high-level clouds typically come with excellent weather. They are quite wispy and can indicate which way the wind way up in the atmosphere is blowing since their tails orient themselves to that direction.
Although the weather prediction when you see cirrus clouds is fair, they may also indicate that a storm is on the way. Pay attention to these clouds, and if they start the get ticker, expect rain within the next 24 hours.
This is the other type of high-level cloud to watch out for. They form like a sheet of moisture high in the sky, that can be quite long and wide but stays thin. These clouds only form when there is an unusually large amount of moisture in the sky. The weather prediction is then within 12 to 24 hours.
We often refer to these low-level clouds as “fog”. These clouds may produce some light rain or snow, depending on the temperature. However, they typically break up as the day warm and may reveal blue skies as they dissipate.
Also referred to as “mackerel sky”. Their appearance resembles the scales of a fish. These middle-level clouds create a layer in the sky of textured clouds that may be spaces through which you can see the blue sky. These are the most common type of mid cloud. You can predict that storms will arrive later in the day.
Clouds that sit within the middle level, cover the entire sky, are thick and produce rainfall within this category. They are often so large that once they are above you, it is impossible to see where they end. If this type of cloud moves in, expect steady rain all day.
When someone pictures the perfect cloud, it is probably a cumulus cloud. These are the stereotypical, fluffy clouds that kids lie on the grass staring at and looking for images. They have flat bottoms and stacked tops, are white, and should be more extensive than they are tall.
You can see them at lower levels of the sky. Cumulus clouds are typically an indication of beautiful weather, now and into the afternoon. However, if these clouds start to build upon their tops, you may be able to expect storms in the afternoon.
These middle-level clouds form a sheet across the sky that is gray or bluish. They are thin enough that the sun can shine through even when it can’t be seen. These clouds indicate that there will be light rain but nothing too severe.
These are low-level clouds. However, they may become stacked so tall that they can extend into the middle and high levels as well. These clouds tend to have a flat bottom. They also have a massively tall top that often takes on the shape of an anvil. These are the clouds that produce the most significant and most dangerous storms, with lightning, tornadoes, and heavy rainfall possible. If you see these clouds, watch out.