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A rare pyro-cumulus cloud billows towards the stratosphere behind the Hollywood Sign as the Station Fire triples in size in California on Sunday, Aug. 30th, 2009. The strangely calm winds -- not normally associated with such blazes -- made the cloud possible. The clouds are created by rapidly rising hot air from the fire. As the air soars up into colder elevations, it cools and reaches dew point, forming the gigantic clouds -- not unlike a thunderhead. So it's smoke and water seen here.
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