Fortunato,
When I was a youngun' (and the world has certainly changed since then) copperheads were a common experience in my area. I personally killed (here comes PETA) three before I became an adult. All were within 50 feet of our house. I have not seen one since 1970 or so. Perhaps the population has declined. But, 'Spaw is right, the cool weather that has already begun is sending them into hiding.
Roger in Baltimore