Hypothermia has to do with the body's ability to regulate temperature, so a person taking alcohol and certain drugs will fare worse than others. Age also plays an important part. A young person I knew, who's snowmachine broke down, was out all night in about 20 Below zero and survived. The rescue people the next morning found him just as he was taking his clothes off ( so he barely made it ). He was however wearing protective clothing. I do believe you are correct. I think people can catch hypothermia even at the balmy temperature of 60 degrees if they are unprotected for a prolonged period of time.