Wildfires have forced evacuations for visitors and staff at two national parks in the US West as the summer monsoon season brings increased lightning to the arid region. Black Canyon of the Gunnison National Park,

A wildfire that's burning in the southern part of Black Canyon of the Gunnison National Park has grown to more than 1,600 acres.

Multiple aircraft are fighting the fire and a federal incident management team is set to take command of the fire first thing Friday, emergency officials said.