Head In the Clouds

by Leslie Aronson — July 4, 2008

Have you ever wanted to be able to predict the weather? Be your own meteorologist? The clouds can often be dead giveaways in assisting with weather prediction, and though the nuanced differences between cloud types can sometimes take a little while to master, it can be a fun skill to have. For details, check out http://www.instructables.com to get a more in-depth approach, the basics of which are outlined below. Basically, clouds are broken into four categories of high clouds, middle clouds, low clouds, and clouds with vertical growth; clouds are also identified by shape.

Cumulus refers to a "heap" of clouds. Stratus refers to clouds that are long and streaky. And nimbus refers to clouds that bring intense weather and are often anvil shaped. High clouds include a variety of cirrus clouds. Cirrus clouds are white wispy clouds that stretch across the sky. By all accounts, cirrus clouds indicate fair weather in the immediate future; however, they can also be an indication of a change in weather patterns within the next 24 hours (most likely a change of pressure fronts). By watching their movement and the direction in which the streaks are pointed, you can get a sense of which direction the weather front is moving.

Middle clouds consist of Altostratus and Altocumulus clouds. Altostratus are grey and/or blue clouds that cover the whole sky and usually indicate a storm sometime in the very near future because they usually precede bad weather. Altocumulus are grayish-white clouds blanketing the entire sky. They tend to look like large fluffy sheets in which there is a lot of contrast between light and dark. If you see them in the morning, prepare for a thunderstorm in the afternoon.

Low clouds include varieties of stratus clouds. Nimbostratus is your standard rain cloud. It is a large flat sheet of grey cloud with a little bit of differentiation. If you see these, chances are, it's raining outside.

Clouds with vertical growth include Cumulus and Cumulonimbus. Cumulus clouds are your stereotypical white "cottonball" clouds. So long as the clouds remain in low clumps floating across the sky, there will be fair weather. However, you need to keep an eye on these clouds because any vertical growth can indicate the start of a large storm. Cumulonimbus are cumulus clouds that have grown vertically into an anvil-like shape. The anvil tends to point in the direction the storm is moving. These clouds bring most dangerous weather such as rain, lightning, hail, and tornadoes.