Asperitas clouds seen in the sky over Ottawa [Video]

A unique form of clouds made an appearance over the skies of Ottawa on Sunday evening.

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The clouds, known as asperitas clouds, are known for their distinctive formation that look like rippling waves.

The cloud formation was proposed and identifed by the Cloud Appreciation Society in 2008.

Rare cloud formations in Ottawa’s west end on Sunday. (Matt Skube/CTV News Ottawa)

The World Meteorological Organization added the asperitas clouds to its International Cloud Atlas in 2015. It is the latest cloud type to be added to its atlas and the first in more than 50 years.

Its name comes from the Latin word for “roughness.”

“The thing about these clouds is, I mean, they’re beautiful to look at, but they’re scientifically really compelling as well, because we don’t really understand why they form,” Dan Riskin, CTV Science and Technology specialist, told CTV News Ottawa on …