What are lens-shaped clouds called How are they formed?

Answer 1

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Lenticular clouds, technically known as altocumulus standing lenticularis, are stationary lens-shaped clouds that form at high altitudes, normally aligned at right-angles to the wind direction. Where stable moist air flows over a mountain or a range of mountains, a series of large-scale standing waves may form on the downwind side. Lenticular clouds sometimes form at the crests of these waves. Under certain conditions, long strings of lenticular clouds can form, creating a formation known as a wave cloud.

Answer 2

Lens-shaped clouds are called lenticular clouds. They are formed when moist air flows over a mountain or obstacle and creates standing waves in the atmosphere, causing the air to cool and condense into these distinctive cloud formations.