WOODLAND PARK, Colo. — A stubborn and towering wildfire jumped firefighters' perimeter lines in the hills overlooking Colorado Springs, forcing frantic mandatory evacuation notices for more than 32,000 residents, including the U.S. Air Force Academy, and destroying an unknown number of homes.

Heavy smoke and ash billowed from the mountain foothills west of the city. Bright yellow and orange flames flared in the night, often signaling another home lost to the Waldo Canyon Fire, the No. 1 priority for the nation's firefighters.

Interstate 25, which runs through Colorado Springs, was briefly closed to southbound traffic Tuesday.