Beautiful January pearlescence glows over lake Mjøsa, SE Norway. Such clouds tend to appear in mid winter, after heavy western winds over the mountains
in the central Norwegian mainland. The wind, carrying moist air from the Atlantic, is then pressed upwards high into the atmosphere by the mountains,
where the moisture freezes into ice crystals, which bends and reflects the sunlight like prisms.
Thus the fantastic colors. Shows best at sunset and an hour into dusk thereafter.