At 5:30 p.m., our contributor Matt Sparx sent us a photo of the wildfire that sparked in Bobcat Ridge south of Horsetooth Reservoir (above).

According to Fox31, the flames were visible as early as 4:35 p.m.  They also reported that, while unconfirmed, the flames could have begun after a power line in the area went down.  (Source)

The view from a Windsor subdivision. --Shelby Taylor-Thorn, TSM