Many Bay Area residents took to social media on Monday to get answers after spotting what they referred to as UFO clouds.
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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!
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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.
So, it might look like a UFO, but it’s actually a lenticular cloud."