Undulatus Asperatus Clouds Observed Over Guatemala

November 19, 2014

Nubes de Escuintla-001

Photographer: Julio Meza; Julio's Web site
Summary Authors: Julio Meza; Jim Foster

This bizarre undulatus asperatus cloud formation was observed at Escuintla, Guatemala on the afternoon of July 5, 2014. The day was rather windy but otherwise no unusual weather was associated with these mid-level clouds. In the few cases where undulatus asperatus have been documented, they've been observed to take shape over relatively flat terrain sometime (2 or 3 hours to more than 8 hours) after thunderstorms were reported. In 2009, undulatus asperatus were recognized as a new type of cloud.

Photo details: Camera Model: NIKON D200; Focal Length: 80mm (35mm equivalent: 120mm); Aperture: f/16.0; Exposure Time: 0.077 s (1/13); ISO equiv: 100.