I was driving into a parking lot with one level building. It was raining very hard. I saw a person running down the sidewalk holding a newspaper over their head. I thought to myself, they are getting soaked and I am going to park in a space closest to the buildings. I pulled into a space then thought I should back out and then back into the parking space. The rain was coming down so hard that noise of it hitting my car was extremely loud. I had notice that when I pulled in the left side of the parking lot, the side away from the buildings was completely submerged under water. As I backed out of the space, I backed right into the flooded area. When I tried to pull forward my back tires just spun. I though, oh no, I back up too far and into the flooded area. The rear end of my car lifted and began to sink into the water, rear end first, deeper and deeper. The lights flickered, and then went completely out, the motor shut off and there was total silence. I was completely submersed in the water with no way out. The door was lock and windows were electric so I could not roll the window down. I thought, no one will know to look for me hear. I was frightened, terrified actually. I felt I was suffocating and then I woke up.