Hundreds of homes were destroyed, at least half a dozen  people were injured, and thousands of acres burned around two cities east of the Rocky Mountains. Boulder County Security Officer Joe Pele said the rapidly spreading prairie wildfire was illuminated by sparks from power lines and transformers that were overthrown by the drought-dried front range winds in Colorado. Boulder County's Danish Emergency Management Agency on Twitter said evacuation orders were first issued to all residents of Superior City, Colorado, with a population of approximately 13,000, and soon afterwards to more than 18,000 people in the adjacent Lewisville community. 

Within hours, the fire struck an estimated 647.5 hectares and destroyed more than 500 homes, Pele told reporters at a press conference. He said the entire subdivision of 370 homes west of Superior was on fire and 210 apartments were lost in the Superior Old Town, along with other apartments in the area. Property damage also included Superior Town malls and hotels. Governor Jared Polis called the fire a "power of nature", saying that the flames would consume landscapes the size of football fields in seconds.

According to the medical network for Centura Health, thousands of people were moved, amongst them about 30 patients and staff at the Avista Adventist Hospital in Louisville, which was closed and completely evacuated late in the afternoon. Some patients were discharged. The rest were moved to another Centura hospital. Spokeswoman Kelly Kristensen says six people were treated for wildfire injuries at UC Health Hospital in the neighboring town of Bloomfield. However, she refused to reveal the nature of the injury or the condition of the patient.