Undulatus asperatus

Asperatus is the unofficial name of a relatively rare cloud formation. The term was proposed for inclusion in the International Cloud Atlas of the World Meteorological Organization, 2009. The name translates approximately to " roughened " or " churned ". Until now, the name has not been included in clouds nomenclature.

Margaret LeMone, cloud expert at the National Center for Atmospheric Research, documented Asperatus clouds for 30 years and looks at it as a new cloud formation. On 20 June 2006 Jane Wiggins photographed a Asperatus formation of an office building in downtown Cedar Rapids, Iowa, United States. In 2009, Gavin Pretor - Pinney came, founder of the Cloud Appreciation Society, on the picture and began to promote the awareness of cloud formation by the Royal Meteorological Society. Jane Wiggins photo was published on 4 June 2009 on the website of National Geographic.

The cloud formation is related probably closest to the subspecies undulatus. Although dark and storm -like in appearance, they usually dissolve on without the formation of a storm. The ominous -looking clouds appear most frequently in the states of the Great Plains of the United States, often in the morning or midday hours following convective thunderstorm activity. The Royal Meteorological Society currently gathering (as of June 2009) Evidence for weather phenomena in which form Asperatus - clouds to explore their education and then to decide whether they differ from other Undulatuswolken.