Went to cold weather training at Ft. McCoy, Wisconsin in late January '86 or '87. The week we were in the field, we had a few nights that got down to -40. I still don't have the vocabulary needed to explain how cold that is. Our old crusty 1stSgt (Vietnam vet with 4 purple hearts) told us, "If you're cold, you ain't moving fast enough." There's a whole lotta truth to that.