Yes. The cloud formed near sunset. Nothing unnatural about it...just a big thunderstorm. Search 'cumulonimbus'.
http://tinyurl.com/7d7cbvd
Here's a Bible-thumping jackass twisting the sighting into an apocalyptic sign.
http://www.youtube.com/watch?v=9Dxu64lzNyY
Ain't Mother Nature grand? ;-))

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