|Lenticularis clouds over Cape Town, South Africa last|
Sunday. Photo by Liza Vaun Bezuidenhout, via Twitter.
Of course, beautiful clouds can happen anywhere, so it's always good to look up occasionally to see what's going on overhead.
Case in point: Cape Town, South Africa last Sunday.
Lenticularis clouds formed over the South African city. These clouds are fairly common, and most often form when winds fairly high up in the atmosphere are quite strong.
Clouds often form when air rises over a mountain, and moisture in the rising air condenses into a cloud, the the air drops down over the mountain or other obstruction, limiting the size of the cloud.
Sometimes the air going up and over the mountain continues in waves downstream, much like the waves you see downstream from a submerged rock in a fast moving river.
|Another view of the lenticularis clouds over|
Cape Town, South Africa. Photo by Kyle Mihof.
Then you get these smooth, shaped lenticularis clouds. They're relatively common, but sometimes they're quite spectacular, looking at like UFOs or something.
Because these clouds are a visible reflection of a wave in the wind over a mountain, they don't move much. And the wind screaming through this clouds often sculpts them into smooth, rounded, layered shapes.
Lenticularis clouds are not dangerous, and are not a sign that scary, stormy weather is approaching. However, they are a sign for airplane pilots that the air is very turbulent.