I watched this one for a while and it did grow, but it was rolling out onto the plains away from me. I've been trying to get some time lapse photos of a thunderstorm blowing up, but haven't been too successful.
I was trying to block a house that was just on the other side of s small hill. Glad you like it, but I am having problems with noise in just about every picture I post these days. The original file doesn't have the noise, it's when I convert to black and white is where it's happening. I wasn't real happy with this and it may not stay very long. If I can't figure it out soon I'll stop posting until I can post something I am happy with.
I scare myself sometimes being able to do that to a photo. I figured the hill was hiding something L()L. When you convert to black and white what kind of levels or curves do you use? Converting straight to black and white should not create noise unless it is pushed with tones. I am not sure what your program has but if it has something like 'surface blur' or 'noise ninja' or ???? Well noise ninja is a plugin for photoshop so I am guessing no on that one. How do you convert to b/w?
One way to help reduce noise is to create a duplicate layer and apply a very small Gaussian blur to it. You want enough to cancel out the noise but not so much where it creates a cloud. Than you can adjust the transparency to see the layer below, you want to adjust it down to bring back some focus and still keep a slight blur on the noise to hide it.