



Photographer: Peter Paul Hattinga Verschure

Summary Authors: Peter Paul Hattinga Verschure; Jim Foster



The unusual cloud formation shown above was captured over Deventer, Netherlands, a little before sunset on December 16, 2013. Wave structures are apparent across this ragged sky, but it's unclear if these 'eyebrow' clouds take the form of undulatus asperatus clouds (Stratocumulus undulatus asperatus), lenticular clouds (Altocumulus lenticularis) or of some other type of cloud. Because there are few geographic obstacles (minimal elevated terrain) in the Netherlands and surrounding areas, lenticular clouds are rarely observed here. In general, undulatus asperatus seem to have a predisposition to occur following convective storms the previous night. But no such storms were noted in the vicinity of Deventer. Nor does the sky have a particularly menacing appearance, typically associated with undulatus asperatus clouds.



Photo details: Camera Model: SAMSUNG WB150F; Focal Length: 5.3mm (35mm equivalent: 32mm); Aperture: f/3.4; Exposure Time: 0.0029 s (1/350); ISO equiv: 80; Software: Adobe Photoshop Elements 8.0 Windows.