Storm clouds

I have never seen any storm clouds like this before. Normally the storm clouds have a flat bottom or just a few puffs on the bottom. This was a crazy storm all around us, but all we got was rain and wind for a few minutes. What I thought was most strange about the cloud was that there was a hole in the center of it where you could see blue sky. That part is just out of reach of the photo on the top left side.