On the evening of the fifth, I noticed some nice convection down to my south over the mountains southwest of Denver. From my vantage point at the Snow Mountain Ranch in Grand County, it was rather distant, but lit well by the setting sun.
I headed up to the reservoir to hang out with my cousins as they fished and take some pictures and noticed some weak cumulus on the mountains to my east (west of Boulder). By the time I got back to the cabin and had settled in to relax for the rest of the night, I thought I caught a flash of light from outside. I went out to the northeast side of the lodge and saw a tower building about twenty miles to my northeast, a tower that was starting to flash like a strobe light. The full moon was also out and off to the south, affording plenty of light to the growing tower. As the updraft continued to intensify, I went in and got a chair so I could enjoy the show.
Even my family, who might normally be put off by my suggestion "you've got to come out and see this" soon found themselves outside, jaws on the ground, watching one of the most beautiful light shows in any of our memories. The flashes were near constant and while I didn't witness any specific cloud-to-ground strokes, the exterior strokes were more than enough to please me.
"I have never seen lightning like that" was a common phrase. (I have, of course, but that's because I'm out looking for it!)
Anyway, enjoy the cycle of the cell as it strengthened, anvilled, and then slowly drifted away before the mid-level cloud deck obscured it.