A very tall figure in Madison County, Iowa

I live in Des Moines, Iowa, but almost every weekend I take my wife and daughter down to the country just outside of Earlham to visit with my parents. The incident happened during the later weeks of November. Maybe the 17th or the 22nd? It hadn't quite started snowing yet, but it was getting colder. We were driving back from my parent's house on Hogback bridge road at about 11:30 PM or so and I will admit to being fairly drowsy at the time, but I have driven that road countless times, tired or not, and have never encountered something like this. My wife and daughter had already fallen asleep by the time we reached the intersection. On the left side of the road I thought I saw something crouched in front of the intersection sign. As we neared the sign, whatever it was stood up and acted like it was going to try to cross the road. My heart skipped several beats at the sheer size of this thing. It was easily 7-8 feet tall, was very skinny/lanky, and was covered with shaggy, matted brown hair. It's eyes reflected yellow in my headlights like a cat's. I recall saying "Oh God." as I swerved a bit in terror but kept driving. After I had passed it and the realization set in of what I just saw I turned and woke my wife up and told her. She acted as concerned as someone who was just woken up could be, but wasn't able to fall asleep again until we got home. I was so scared that I called my mother who lives only a couple of miles away and told her to lock her doors. She agreed to do it, but didn't believe that I had seen anything, of course. I've been researching the possibility of sasquatches ever since then and came across this site. One thing that was odd, is that several of the other Iowan sitings were in November as well. Perhaps this could indicate a migratory behavior?