io9 just introduced us to the “unique meteorological phenomenon” that is the roll cloud: “a type of arcus cloud — a dense and horizontal cylindrical structure that often appears ragged and turbulent.” They hang out with thunderstorm gust fronts and only occasionally deign to show up, and when they do they literally look like they’re rolling through the sky like a kind of horizontal tornado.

Here’s one:

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And we know what you’re thinking: That totally looks like a joint. (Or, at least, that’s what we’re thinking, so … back us up here.)

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Seriously:

I mean.

roll cloud2

DocJ96

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Yup.

You know we’re right on this. Roll clouds: Smoke ‘em if you’ve got ‘em!