Astronomy Picture of the Day -- A Roll Cloud Over Uruguay

NASA ^ | Sunday, June 12, 2016 | (see photo credit)

[SunkenCiv]

Explanation: What kind of cloud is this? A type of arcus cloud called a roll cloud. These rare long clouds may form near advancing cold fronts. In particular, a downdraft from an advancing storm front can cause moist warm air to rise, cool below its dew point, and so form a cloud. When this happens uniformly along an extended front, a roll cloud may form. Roll clouds may actually have air circulating along the long horizontal axis of the cloud. A roll cloud is not thought to be able to morph into a tornado. Unlike a similar shelf cloud, a roll cloud is completely detached from their parent cumulonimbus cloud. Pictured above, a roll cloud extends far into the distance in 2009 January above Las Olas Beach in Maldonado, Uruguay.

[SunkenCiv]

[Credit & Licence: Daniela Mirner Eberl]

[SunkenCiv]

The Big One

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[Paine in the Neck]

A common enough event in Australia that it even has its own website http://morningglorycloud.com/

[BenLurkin]

Nice!

[OldNewYork]

The world is still full of beauty and wonders. Thanks for posting this.