8* F. and a 15 mph wind would put you right about -10 * F windchill. BRRR! If you are going to have your water bottles in the bag with you you might as well heat them up and stick them down by your toes. It will help for awhile at least. I've heard of folks doing the same thing with a pee container but I haven't got that desperate yet. <img src="/images/graemlins/grin.gif" alt="" />