Timelapse shows a river of cloud rolling over the canyon
Low cloud brought by colder weather poured over the red rock walls in slow waves.
The timelapse shows a dense bank of cloud settling on the rim of a deep canyon and flowing slowly across the gorge, breaking apart in one place and gathering again in another.
Shadows from the cloud drift over layers of red and orange rock, revealing the depth of the canyon tier by tier. Towards the end, the sky clears and sunlight falls on the far side of the valley.
Forecasters point out that conditions on high plateaus can change quickly at the turn of the seasons.
