A lightwieght military style poncho is my base item. It is far from the best dedicated rain gear, but for dual purpose use as a floor for my siltarp it is invaluable. G.I. wool watchcap and glove liners are again very light and compact. A warm head and fingers may give me a few moments of TUC to get 'squared away' in foul weather. Likewise a wool scarf can add comfort and venting for little space. If two pair of socks are good, 3 are better and a wool shirt and pants, some thin woolen longjohns( two piece are easier for toilet calls, but one piece is warmer and faster to put on for me)have me literally covered. Living in California where everyday is 'Casual Friday' I am actually overdressed compared to everyone else in warm weather. It's the cold I worry about.I hopefully can grab a coat. But if not, a thin shirt and woolen can be improved upon with my secret insulating material WIGGY hasn't heard of. It's called crumpled newspaper stuffed in between a thin shirt and the woolen.