Meteorological optical phenomenon

[DaveC426913]

Snapped this pic the other day. At first, I was drawn by the subtlety of the central tip of the cloud, which is illuminated by reflected light from the sunlit mound of cloud between it and us, but I was wowed by these fanlike structures in the sky above the cloud.

Those are not digital artifacts or anything, they are naked-eye effects. They are some sort of shadow, cast over the top of the cloud by the sun. I don't quite understand what phenomenon has created them though. Any takers?

 

[Andre]

That's most unusual. The cumulus cloud clearly indicates instability while the reflections and shadow indicate a hazy smoggy layer which usually only exist in stable high pressure subsidence inversions.

So, could this be a transient cold front just about to pass? Just a guess.

 

[jim mcnamara]

Looks like crepuscular rays. Dunno.

Look here for very good details:

http://www.atoptics.co.uk/rayshad.htm