Many Bay Area residents took to social media on Monday to get answers after spotting what they referred to as UFO clouds.
We asked NBC Bay Area Chief Meteorologist Jeff Ranieri to take a look and explain. Here's what he said:
"What you’re looking at is a classic example of a lenticular cloud. These cloud shapes can often take on the appearance of something out of a science fiction movie!
So what’s happening here? Well, these clouds are created when moist, stable air flows over a mountain or hilltop. When the air passes over the mountain or elevation, it condenses, forming a cloud.
The wind pattern then compresses the cloud, leaving it in this very unusual and cool-looking flat shape.
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So, it might look like a UFO, but it’s actually a lenticular cloud."