The day started with a white-out with the canyon completely obscured from view. Then, in–what seemed to be just moments–the fog dropped and settled below the rim. As noted on Twisted Sifter: “The phenomenon is known as ‘temperature inversion’ where warm air acts as a lid to seal cool air near the ground, trapping fog in the canyon and preventing it from rising. According to the National Weather Service, the atmosphere’s temperature profile is most prone to inversion during the winter, when long nights allow for air near the Earth’s surface to become unusually cold.”
Some of the best photographs of the inversion were taken by Park Ranger Erin Whittaker and are found here: http://www.twistedsifter.com/2013/12/grand-canyon-floor-filled-with-fog-november-2013/.
Another fascinating phenomenon made possible by this weather event was the Brocken Spectre with Glory which my husband experienced. With bright sunshine behind him, his shadow was projected onto the fog and a rainbow encircled his shadow. Neither Gene nor I had our cameras with us so we were unable to record what happened but a friend at the canyon (Mike Buchheit) did capture his own experience of this. His photo can be found at: https://www.facebook.com/grandcanyonassoc.
Another experience of the Brocken Spectre with Glory in another part of the world is depicted in the featured photograph (details below):