I must say it didn't take much to notice these spectacular, fast moving storm clouds forming in the middle of the afternoon! It was very fascinating to watch them change shape so quickly. I need to confirm these clouds, but I am assuming that they are called ''shelf clouds". Shelf clouds form at the leading edge of a gust or very strong winds flowing down and outward from a storm. A shelf cloud should be seen as a harbinger of strong winds, so a reminder to take caution and understand that Mother Nature can be very powerful.