Ghost Sighting or Dust Devil? Analyzing this Las Vegas ‘Sign’ [VIDEO]

When I saw this story on TV this morning I could not believe it. I posted about the passing of Betty Willis, designer of Las Vegas' iconic welcome sign, just 2 days ago. Now here is this extremely rare, powerful and downright creepy footage of a dust devil right next to it?

Come to find out, this footage was shot on the Friday before Betty's passing. But I've been to this town over 20 times and hiked through many of the different canyons and valleys of the Mojave and I've never seen a dust devil with this kind of intensity.

Despite my skepticism on most of these matters, I'm still filing this under the heading 'Supernatural'.