shtf, CLOTHING better be MOST of "shelter'

gear, cause you are unlikely to always be able to set UP a shelter,and you are very likely indeedto have to be ok, climatewise, while just sitting or while moving. A set of Expedition Wt Thermax longjohns( preferably fastened together at the waist, to prevent heat loss at the waist, and with a folding bottom, to let you take a crap) goes a LONG ways towards keeping you dry and warm. Ditto a set of Gore Tex cammies. One set of "spare" Gore Tex socks is in BOB, for wet footing conditions. Two sets each of polypro socks and Thermax hiking socks. Change them out often, at least daily, washing them and your feet, go a long ways towards keeping your feet healthy. Of course, you should just AVOID, or LEAVE an area where the climiate or conditions making living any tougher than it has to be. Even the BIRDS know enough to migrate twice a year.