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What are those wispy clouds in the sky?

By Brent Watts, bwatts@wdbj7.com
Published On: Aug 06 2014 10:44:13 AM EDT
Updated On: Jul 17 2014 10:04:54 AM EDT

The skies have turned a deep blue and now you're mesmerized by clouds that seem like cotton candy being pulled apart.

Chances are, you're looking at cirrus clouds that have formed around 16,000-to 40,000 feet.

COLD AIR ALOFT

Air temperatures aloft are extremely cold, sometimes as much as -20° to  -40° F. This means any water turns to ice crystals and forms the cirrus clouds.

Sometimes, the relative humidity is lower aloft, which can lead to deep blue skies which accent the cirrus clouds.

Upper Levels Temperature and Humidity

GUSTY WINDS

Winds aloft are typically much stronger than at the lower levels. Sometimes the jet stream can be found streaking through the sky at the same level where cirrus form. The stronger winds can often blow the ice crystals around, giving them that wispy look.

The stronger the wind, the more "stringy" the clouds.

Upper-level temperatures and wind speed

BACKGROUND

Cirrus clouds get their name from the Latin word cirrus, or curl of hair, tuft or wisp. Cirrus cloud is a member of the ten fundamental cloud types and are wispy white high-altitude cloud formations. In fact, they are the highest of the main cloud genera, popularly known as 'mares' tails they may even form in the upper troposphere.

WHAT DO THEY MEAN?

Cirrus clouds are typically found during changes in the weather. When accompanied by blue skies, they are the true fair-weather cloud, especially when they appear to be dissolving which can indicate high pressure and improving conditions.

However, Cirrus are often an indication of the leading edge of a warm front, especially if they are spreading out from the west or south-west, and thicken into a denser sheet of cirrostratus. It can often predict an approaching storm system is 24 to 36 hours away.