Estimated to have burned 173,536 acres since August 13, the blaze prompted authorities on October 16 to order mandatory evacuations for parts of Larimer County, north of Denver.“Residents and business occupants should evacuate the area immediately and as quickly as possible due to immediate and imminent danger,” authorities said.“Do not delay leaving to gather belongings or make efforts to protect your home or business.”This time lapse, captured by Boulder resident Meghan Brammer, shows a shelf of thick smoke gliding across the sky, contrasting with the sun-tinted clouds and bright blue sky above. Credit: Meghan Brammer via Storyful">