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Watch for Mare’s Tails

“Mare’s tails” are the long, wispy, feathery clouds one sees occasionally in an otherwise cloudless sky. But note them well. Some of them are marvelously beautiful, and nearly all have significance to anyone interested to know the coming weather.

Mare’s tails portend a change. Sometimes the first sign of the change to come is a single long mare’s tail, stretching itself high and lonely against the blue sky. It looks somewhat like an elongated ostrich plume.

If the feathery wisps at the tip turn up-ward, you may count on rain (in warm weather) within the next thirty-six hours or so, and perhaps much less time. If the tip is downward, there will be some wind, but probably no rain. Not long after the first mare’s tail appears, there may be others forming and appearing, and they may make a startlingly beautiful sky. Gradually a more solid-looking cloudiness will form, the mare’s tails will be absorbed into this or vanish, the sun will become pale and may disappear, and the whole sky will grow overcast.

Watch for mare’s tails and learn for yourself how well you can do a little weather forecasting. The more correct name for mare’s tails is cirrus (singular) and cirri (plural). They are said to have been seen as high as ten miles, though their average altitude is about five and a half miles. Their particles are ice. These clouds give rise to halos, coronae, and other optical appearances.

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