Overcoats for the Cold: Rag & Bone wool and nylon Marwood coat with removable shearling collar, $995 at Tenet, Southampton, N.Y.; Uniqlo (+J) cotton shirt, $49.90 at Uniqlo; A.P.C. wool pants, $325 at A.P.C.; Louis Vuitton leather derbies, $1,100, at