Unusual Clouds: Lenticular, Virga, Mammatus, Kelvin-Helmholtz
One of the enjoyable pastimes of weather addiction is cloud watching. Here are some rare and unsual cloud formations that I have seen—lenticular clouds which look like flying saucers to virga clouds which look like jellyfish to mammatus clouds which look like udders. Have you seen them?
I live in New Mexico, where the sky is such a deep blue that native tradition believed turquoise was small pieces of fallen sky. Part of the joy of being outside is just to gaze into the endless blue and watch the clouds form, shift and dissolve.
Scientists explain that warm air collides with cooler air, causing the moisture in the air to condense from gas to droplets or frozen particles. Science aside, clouds form weird and wonderful shapes and images.
Here are some relatively rare clouds types I have seen here in New Mexico.
Jellyfish clouds or Virga
Image: Courtesy of NOAA
These clouds are common in the desert, but rare elsewhere. Those jellyfish tendrils are rain that can’t reach the ground. They occur when the ground heats the air so it evaporates the falling rain.
Image: Courtesy of Wikipedia
Anyone who has milked a cow knows how these clouds got their name. They are sagging pouches that form on the base of larger clouds, like the anvil clouds of thunderstorms (where they sometimes indicate a potential tornado.) There are many theories why these puffs of moisture form under the clouds but so far there are no real answers. While an individual lobe usually lasts only 10 minutes, the boiling cluster can linger for hours. It’s an incredible sight.
Image: Courtesy of Windows to the Universe, Benjamin Foster/UCAR
Named for Lord Kelvin and Hermann von Helmholtz, these weird clouds appear when two layers of air are traveling at different speeds and the faster top layer ripples the moisture of the lower air mass. They are rare and as a sign of unstable air, seldom last longer than 10 to 15 minutes. In the West, they sometimes appear when cool air races up one side of a mountain and glides over the air on the other side.
Lenticular clouds look like flyer saucers! They seem to get their shape because they form downwind of hilly terrain. I've seen some amazing examples in the Southwest near the mountains.
Have you seen these beauties?
The most fascinating clouds of all might be noctilucent clouds. These are clouds from outer space, formed by meteor dust. These electric blue clouds are only seen in summer.
Learn more about noctilucent clouds!