Horizontal Roll Clouds this week...

[J Gontesky]

This week, I have observed a type of horizontal roll cloud on two occaions: once on Monday morning and then again this morning here in northeast Kansas. On both occasions, the clouds formed behind overnight convection just prior to the skies clearing. This morning's event was not particularly well-defined, but Monday's was. Both events were faintly visible on radar - particularly at the lowest elevation scans.

While I feel I have some semblance of what causes these, does anyone here want to take a stab at a concise explanation as to the dynamics involved in such an event?

I also used this as my first attempt at stitching together a panoramic image with the Canon PhotoStitch software. While the seams are still visible, I was pleased at how simple the process was...with a little more effort, I'm assuming I could get a fairly good product out of it. I won't insert the pano here since it is so wide, but here's the link to it and more images:
http://www.notesinthemargin.com/archives/402

 

[Skip Talbot]

Hey J, I just posted a shot of one I caught in a previous thread. It was actually the base of a large mesocyclone before the parent storm went elevated and orphaned it. The gust front continues to extend out from the storm, condensing rolling convection as it goes, while the storm's updraft long since fizzled and the convection from the tower evaporates.