WAWONA — The smoke creeping up from a steep hillside near this small California community 27 miles south of Yosemite Valley was a sure sign that a spot fire was burning, hidden beneath the tall pine trees.

In years past, firefighters might have proceeded with just the limited information provided by a helicopter operator struggling to see through the haze.

Instead, a California Air National Guard aircraft with infrared capability flying thousands of feet above the Ferguson Fire was able to determine that firefighters were facing not one spot fire but seven, which were quickly growing together.