From KY3.com Weather:
A storm system moving across the Ozarks on Monday morning produced widespread interest for more than just the thunder and rainfall it produced. As the system moved across the region, the balance of instability aloft and a relatively stable low level airmass helped to produce what was likely a potentially new form of clouds now under review by the World Meteorological Society or WMO. The cloud type in question has been named, "Undulatus asperatus".
It seemed as though I was looking at rapids on a river --- from underneath! We did get some rain from these, but not storms. The temperature was only about 62 degrees at the time and a little breezy.
Here are more photos I took of this awesome sight: