A wildfire west of Potosi Mountain that has produced plumes of smoke visible from the southwest Las Vegas Valley has more than doubled in size. A screenshot from the National Weather Service's Las Vegas forecast office X account shows camera footage of a wildfire on Mount Potosi that was posted Aug. 7, 2026. A wildfire in the Potosi Mountain area that produced plumes of smoke visible from the southwest Las Vegas Valley had burned 77 acres as of Saturday afternoon, according to the Nevada Wildfire Information Dashboard. The National Weather Service’s Las Vegas office said the wildfire, on the west side of the mountain, was caused by a lightning strike from a thunderstorm. Potosi Mountain, near state Route 160, is a prominent peak at the southern end of the Spring Mountains.