The most dramatic cloud I've ever seen went by today. It came from the north (see other photo: http://365project.org/kwind/extra-shots/2014-03-16 ) and slowly moved south right over our house! It was like a wave! It had been sunny, then got very dark, there was hail and rain and even a rainbow that was so large I couldn't get the whole thing in my frame.
Every now and then you'll come across a picture of an unusual cloud formation such as this one. I guess there are a lot of atmospheric conditions taking place that causes them. I am glad that it was you that was in the right place at the right time!
Wow what an amazing cloud and great timing on your part, so dramatic. We had a similar cloud over Southern Sydney a couple of weeks ago and there were some incredible photos.
@edie Your comment literally made me LOL!