Cloud pictureEach cloud indicates too much water vapour in a given parcel of air. Below the dew point the air cannot longer hide the vapour and tends to build visible water droplets - the clouds. Lenticular clouds are formed by the same process, but stay in place, because the lack of wind. Valuca’s Photosite shows more photos of this UFO shaped weather phenomenon.

Via: Ehrensenf.de, Picture credit: Valuca