Most schoolchildren learn the basic clouds in elementary school science class. “This is a cumulus cloud. That is a stratus cloud,” etc. But what teachers don’t explain is there are some stranger cloud formations that almost defy belief. These clouds can be equally beautiful, scary, and surreal. Some of the following photos have been digitally manipulated, but they represent real phenomena that, if you’re lucky, you’ll have a chance to see one day.
These lenticular clouds over the Sierra Nevada mountain range are tinted a spectacular red by the sunset. Lenticular clouds can form when moist, stable air flows over mountains, and they may remain in place for long periods of time. Not surprisingly, these clouds have frequently been mistaken for UFOs.
The pointed spires of the unique Air Force Academy chapel in Colorado Springs, Colo., appear ready to puncture the mammatus clouds hanging overhead. Mammatus clouds tend to develop under a cumulonimbus cloud, by sinking, cool air with a high water or ice content. The appearance of mammatus clouds generally indicates the strongest part of a thunderstorm has passed.
An ominous-looking shelf cloud moves over Race Point Beach in Cape Cod. Shelf clouds form when cooler air descends in a thunderstorm’s downdraft, then spreads laterally near the Earth’s surface. When warmer, moister air is lifted at the leading edge and condenses, a shelf cloud can result.
Niccolò Ubalducci is an avid stormchaser who has posted thousands of his photos, many quite spectacular, on Flickr. He captured this image of a wall cloud in 2010. These clouds, which drop out of the base of cumulonimbus clouds, often spawn tornadoes. They’re certainly not as rare as the other cloud formations in this story, but we just loved this photo.
Mick Petroff captured this incredible image of a Morning Glory cloud formation in northern Australia. These extremely rare “roll cloud” formations can be found around the world, but are most common in Australia’s Gulf of Carpentaria. These clouds, which can be hundreds of miles long, can be accompanied by intense weather — wind squalls, sharp vertical air displacement, and pressure rises at the surface. According to National Geographic, “The rolling motion is the result of winds changing speed and/or direction at the inversion — when the air temperature reverses from its usual state, resulting in warm air on top of cool air — along which the weather disturbance is traveling.”
This is Not a Tornado … Really
This photo reportedly showing a tornado has been circulating for several years online. It actually depicts a wall cloud from a mesocyclone, not a tornado. According to USA Today, this photo was taken in Orchard, Iowa, in 2008.
A New Sensation
A woman named Witta Priester captured this incredible image of an unusual cloud formation in New Zealand in 2005. Asperatus clouds, although related to undulatus clouds, have been proposed as a new cloud type by the Cloud Appreciation Society (yes, there really is such an organization). They form when heavy rain or a thunderstorm cause a wave action in the air, mixing warm and cold layers of air. While the image appears as if it might have been dramatically enhanced with photo software, it is totally legit; NASA has run the photo in its popular Astronomy Picture of the Day feature. (The image is copyrighted and we’re using it under Fair Use provisions of copyright law.)