Colorado officials expanded mandatory evacuations on Wednesday after the state’s largest active wildfire, the Lee fire, pushed south into Garfield County for the first time. The blaze, which has grown to about 120,650 acres and is only 4% contained, prompted orders for residents northwest of Rifle to leave immediately as winds drove flames across the Rio Blanco–Garfield county line. Fire crews are trying to hold lines along Colorado Highway 13 while preparing additional containment barriers to the south. Farther north, Routt County authorities issued evacuation orders when the 750-acre Crosho fire crossed from Rio Blanco County into Routt National Forest. Residents from east of Crosho Lake to Routt County Road 17 were told to evacuate, and several local roads were closed. The Crosho fire, detected two days earlier, is burning on both U.S. Forest Service land and private property. The Lee and Crosho incidents are among five lightning-sparked wildfires—the others are the Elk, Oak and Stoner Mesa fires—that have scorched more than 143,000 acres on Colorado’s Western Slope in recent days. The National Weather Service has posted fire-weather watches for much of western Colorado on Thursday and Friday, warning that extremely dry conditions, gusty winds and potential dry thunderstorms could hamper containment efforts and ignite new starts.