Clouds (Elementary)

Looking at clouds helps us make sense of the weather. Clouds form when tiny water droplets in the air join together and get bigger. Stratus clouds are layered clouds. Cumulus clouds are puffy clouds. Cirrus clouds are wispy clouds. Nimbus clouds are rain clouds.

People who study the weather are called meteorologists. They put together words to describe clouds. Here are what the different clouds look like (look at the diagram too).

l. High clouds are found at the top of the atmosphere layer that lies closest to Earth (the troposphere). High clouds are always above 10,000 feet. High clouds include: cirrus clouds that are high and wispy, cirrostratus clouds that are high, wispy and layered, and cirrocumulus clouds that are high, wispy and puffy.

1. Cirrus clouds are the most common clouds that you see way high up in the sky. Winds blow them into long wisps called, mares’ tails. They move across the sky from west to east. They are a sign that good weather will follow.
2. Cirrocumulus clouds are small, rounded puffs of clouds. They seem to ripple across the sky in rows, like fish scales. That is why they are called a mackerel sky.
3. Cirrostratus clouds are thin sheets of high clouds that spread across the whole sky. They are so thin that they often just look like a hazy sky. They can show a ring around the sun or moon. With cirrostratus cloud cover, there can still be enough sun to form shadows on the ground.

ll. Middle clouds are found between 6,500 feet and 26,000 feet up in the sky. They include: altostratus clouds that are layered and about midway up in the sky and altocumulus that are puffy and about midway up in the sky.

1. Altostratus clouds are huge sheets of grayish clouds that fill the sky. Only a dim outline of the sun shows through altostratus clouds and no shadows show on the ground. This is sometimes called a watery sun. Altostratus clouds are often pushed in front of a snow or rainstorm on the way.
2. Altocumulus clouds are gray and puffy. They can spread across the sky in little rising masses called little castles. They are the clouds that, on a hot, sticky summer day, grow into thunderheads.

lll. Low clouds are found between the ground and up to 6,500 feet. They include: stratus clouds that are layered, stratocumulus clouds that are low, layered and puffy, and nimbostratus that are rainy and layered.

1. Stratus clouds form a low, solid, gray layer across the sky. They look like a fog bank that hasn’t reached the ground. They sometimes spit mist and light rain.
2. Stratocumulus clouds are low bunches of gray clouds. They often form at sunset after a storm. They are not a solid band. Blue sky can be seen around them. Sunlight will stream down between them. It sometimes looks like a spotlight from the heavens.
3. Nimbostratus clouds are dark, wet cloud layers. They bring light to moderate rain. You cannot see the sun through nimbostratus clouds. They don’t let enough light through for shadows on the ground. They make for a very gray day. They often form another a lower ragged layer of clouds that speed by in the wind, called scud clouds.

lV. Clouds that Grow and Rise include: cumulus clouds that are puffy and cumulonimbus clouds that are rainy and puffy.

1. Cumulus clouds are the most well known clouds. They are the cottony puffs that form shapes as they rise. They have flat bottoms that are darker than the rounded tops and are surrounded by blue sky. They are fair weather clouds. Cumulus clouds can build and rise into giant clouds called towering cumulus.
2. Cumulonimbus clouds are thunderheads. These are low clouds with dark bottoms that rise into giant rounded tops. When their growing tops hit higher winds, they get cut off into an anvil-shape. These could have rain, snow, hail, and lightning. They can even sometimes spawn tornadoes.

Airplanes flying at high altitudes can even form clouds. Contrails are cirrus-like trails of clouds that follow high-flying planes across the sky.