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Altostratus undulatus cloud

earth science Maturity 5-7 Next article →

Some clouds look like waves in the sky. This is the altostratus undulatus cloud. It is a type of altostratus cloud. These clouds have special wavy shapes called undulations. You might see wavy bases on the clouds. Often, these waves are hard to see with your eyes. They are still a very interesting part of our sky.

These clouds form in a specific way. They appear during early stages of return flows. These flows are becoming unstable. This happens near an inversion surface in the air. The wavy strips of clouds stay near that surface. The air moves in a way that creates these patterns. It is a slow and steady way the sky changes.

Scientists and watchers use many names for these clouds. Some people call them billow clouds. Others call them wind row clouds. You might also hear them called wave clouds. These names all describe the same wavy shapes. These shapes can look like single lines. They can also look like many lines that have merged.

You can find these clouds in certain places. They appear over the southern plains of the United States. They often show up when the surface temperature is cool. The air stays relatively cool near the ground. This helps the clouds form their wavy shapes. These specific conditions make the patterns easy to spot.

Think about how waves move in the ocean. These clouds work in a similar way. Instead of water, the air creates the waves. The undulations are just patterns in the air. They can stretch far across the sky. Sometimes they stay small and close together. They show us how the air moves above us.

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