A Vulcan lute on Aldea. The Vulcan lute (sometimes referred to as Vulcan harp, Vulcan lyre, or Vulcan Lyrette) was a twelve-stringed instrument, played on the planet Vulcan, that was tuned on a diatonic scale and noted to be very soothing.
Keystone Average Weather. 1  The highest monthly average temperature in Keystone for July is 54 degrees. 2  The lowest monthly average temperature in Keystone for December is 14 degrees.  The most monthly precipitation in Keystone occurs in January with 0 inches.
On average, there are 285 sunny days per year in Costilla County, Colorado. The July high is around 81 degrees. The January low is 3. Our comfort index, which is based on humidity during the hot months, is a 74 out of 100, where higher is more comfortable. The US average on the comfort index is 44.