Scud before Congestus
Fleeting and small, the flimsiest shreds of scuddy cloud material drift darkly in front of the face of a powerful bomb of atmospheric energy release, in the form of cumumlus congestus clouds. Why was the scud so dark, the convection so bright? The answer is in differential lighting. The scud was closer and lower in the sky, in the shadow of some other clouds behind our backs. The little cloud rags look even darker thanks to silhouetting in the vivid reflection of near-sunset light from those big convective turrets.
3 SSE Yuma CO (21 Jun 10) Looking SE