As I was getting ready to park at work in Decorah Iowa, I notice a very bright piercing white light up in the sky. I probably wouldn't have noticed it normally, but it was the only light in the sky since it was completely overcast and still dark outside. I couldn't tell how high up it was, but it wasn't low at all. It had to be at least a half mile up or higher. I had a hard time at first thinking it was not a star, but the cloud coverage was thick, and it was far brighter than a star would be even when there would be no cloud cover. I stayed outside for approximately 10-15 minutes until I went into work because I was going to be late. During the whole 15 minutes the light never moved, changed shade or colors at all.