Last Thursday an uncommon event occurred at the Grand Canyon — a total cloud inversion. Temperature inversions occur in many places across the US, but when they happen at the Grand Canyon, the canyon fills with clouds. Inversions happen several times a year in the canyon, usually in the winter. This time, however, in addition to the usual photos, Park Service staff member Michael Quinn caught 15 minutes of the event on a one-minute time-lapse video. If you prefer, enjoy it with music added. I opted for the silent view, the way clouds usually present themselves. Like fog, they slip in on little cat feet.