A couple of days prior to this shot, we had a light snowfall. The temperature was around -5˚C and the snow was light and almost like powder. Just after it stopped snowing the wind picked up and created these patterns. Note the blueish tone of the shadows lit by a clear blue sky, whereas the sunlit areas have a warmer tone due to the low angle of the sun.
White balance set to Daylight, shot 1 hour before sunset early February.