I don't know what this "cloud" is called but I went outside (balcony) to pray for rain, LOL, and then I noticed this HUGE cloud rolling along (right on top of) the lake. It was moving from Toronto, westward, and heading right towards Port Credit. I was hoping it was a rain cloud of some type. Suddenly, it changed direction and headed south/southeast out across Lake Ontario. It was very strange and eerie to see this thing. Ignore the 4X magnification of some of the pics; I was trying to capture the size of it - it was huge in both height and width!! Unfortunately, we have not had one drop of rain and it is still hot 'n humid :(