Yesterday evening, we were in Colorado Springs. Looking back towards Mike and Chris’s house, we saw a beautiful thundercloud: white in the fading light, and more active than I had ever seen before; flashes of lightning illuminated the cloud every few seconds. Mike videoed it for a while; the photo shows one flash. To give an estimate of the size of the cloud, the buildings in the foreground are less than 1 kilometer away; the cloud is more than 30 kilometers (20 miles) away. I’ll try to put the video up at some point, but cannot convert it to a reasonable size at the moment (the original is 89Mb for just over 1 minute…).