UFO cloud

Lenticular cloud over Butte, Montana.

Flying saucer like cloud in blue sky over gray mountains with rusty mining equipemnt in foreground.

Image via Karen Racette.

It looks a lot like a UFO … but it’s what’s called a lenticular cloud. These lens-shaped clouds typically form where stable, moist air flows over a mountain, and they can appear and disappear quickly. Karen Racette captured this one floating over Butte, Montana, on October 7, 2019.

More photos of lenticular clouds, plus a word about how they form.

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Eleanor Imster