Here's a more detailed description:
* Appearance: They are thin, delicate, and often arranged in parallel lines.
* Composition: Cirrus clouds are composed of ice crystals, which form at high altitudes (above 6,000 meters).
* Weather Implications: Mares' tails usually indicate fair weather, as they are associated with stable, high-altitude air. However, they can sometimes precede a warm front, signaling that a change in weather is coming.
* Variations: While the term "mares' tails" typically refers to cirrus clouds, the term can also be used to describe other wispy clouds, such as cirrocumulus clouds, which appear in smaller patches or ripples.
In summary, "mares' tails" are a beautiful and often predictable sight in the sky, usually signifying good weather.