I was in the US last month and awoke to find a really dark, heavy sky.

I took some photographs and on scrutinising them a little later discovered the clouds to be dotted widespread with what appears to be cylinder shapes.

I have cropped part of the photo to show what I am seeing and highlighted the shapes with green arrows.

The lens of the camera is not flawed, neither was this moisture on the lens.

[Linked Image]

Has anyone any knowledge of this phenomena?