The shot was taken before a sailing competition. The boats were preparing for the start. The clouds were also getting bigger very quickly and we knew we were going to have a big storm, as usual for hot summer days.
As the sky was getting darker, I thought it would be a good idea to put one of my cameras in a water housing in case it would start pouring. As I put in the last screw of the housing, the wind started to blow stronger. A couple of seconds later we were caught in heavy rain and the sky was almost black as night.
All the boats were behind me in the dark but one of them was in line with the blue sky behind the storm. I took a couple of shots but this is the only one where there isn't too much water everywhere and you can see something!