This photo was taken on December 30, 2016, just after sunrise. The sky was full of wavy clouds. There were waves superimposed on waves and the pattern was especially evident in the southeast where the Sun was rising. Elsewhere the sky was not nearly so dramatic which shows how important light is to photographers. It can make or break a picture. Without the low Sun angle these clouds would appear "ho-hum," even though they are not.
The Weather Briefing Blog