Which type of lens-shaped cloud formation, often mistaken for Unidentified Flying Objects (UFOs), typically forms downwind of hills and mountains?

💡 Explanation:

Lenticular clouds are stationary, lens-shaped clouds that form in the troposphere, usually aligned perpendicular to the direction of the wind. Due to their unusual, smooth, saucer-like appearance, they are frequently cited as the explanation for many UFO sightings.