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If you’ve ever looked up and wondered, “What type of cloud is that?” this piece is for the budding nephologist (person who studies clouds) in you. By observing clouds, you can predict the incoming weather!See our Guide to Clouds with pictures of common cloud types in the sky and what theymean.
Types ofClouds
Some clouds are as high as a jet; others kiss mountaintops. Some are white puffs, and some are grey and lumpy. Overall, there are three different types of clouds: high, middle, and low.
I. HighClouds
Bases start above 20,000 feet, onaverage
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1. Cirrus: Thin, feather-like, wispy clouds which are strands of ice crystals.
Weather prediction: A change is on itsway!
2. Cirrocumulus: Thin clouds that appear as small “cotton patches.”
Weather prediction: Fair, but cold. In the tropics,hurricanepotential!
Trivia: Sometimes, this is called a “mackerel sky” based on the folklore, “Mare’s tails and mackerel scales make tall ships take in their sails.” These clouds can precede an approaching warm front. Warm fronts can bring veering winds and precipitation. So, a sailor might take in hissails.
3. Cirrostratus: Thin white clouds that resemble veils that tend to cover the whole sky. They are more common in winter.
Weather prediction: Rain or snow will arrive within 24hours!
II. Middle- to Low-LevelClouds
Bases start at between 6,500 and 20,000feet
1. Altocumulus: Gray or white layers or patches of solid clouds with rounded shapes, and they often appear as fluffy ripples. They are made of liquid water, but they don’t often produce rain.
Weather prediction: Fair andpleasant!
2. Altostratus: Grayish or bluish layer of clouds that can obscure the Sun, usually covering the entire sky.
Weather prediction: Be prepared for continuous rain orsnow!
3. Nimbostratus:Dark, gray, shapelesscloud layers containing rain, snow, or icepellets.They are often thick enough to block out the Sun.
Weather prediction: Gloomy with persistent rain orsnow
III. LowClouds
Bases start below 6,500feet
1. Stratus: Thin, gray-white, sheetlike clouds with low bases covering the whole sky.
Weather prediction: Fair, but gloomy. They may bring drizzle or snow, but won’t dump too much precipitation because they are sothin.
2. Stratocumulus: Rounded cloud masses that form in a layer. Often, they have a darkish tint instead of bright white.
Weather prediction: Fair weather for now, but a storm might be on itsway.
IV. Low Clouds With VerticalDevelopment
Form at almost any altitude and can reach more than 39,000feet
1. Cumulus: Fluffy, white, cotton-ball cloudswith flat bases and dome-shaped tops.
Weather prediction: Fair weather is instore!
2. Cumulonimbus: Large, dark, vertical clouds with bulging tops that can grow to towering heights on hot, humid days.
Weather prediction: These bring showers, thunder, andlightning.
Want to see more cloud pictures?Imagine clouds shaped like jellyfish and flying saucers!See Rare Clouds and Pictures.
