SWAMPUS--I always heard it slightly different, at least the South part--"Wind's in the South, baits in the fish's mouth." There's no question that weather fronts affect fishing. It has been my general experience that trout feed well ahead of a strong storm front. As for the Smokies, prevailing winds tend to be from the southwest.
I put considerable credence in old "sayings" about weather and firmly believe that there is a lot of truth in them. My Grandpa Joe was full of such folk wisdom, and years ago I used some of it for several years in a little "weather wisdom" section for some country magazine (the title escapes me just now). Some of my favorite bits of weather wisdom (and almost all of them rhymed) dealt with snow. "Snow hanging on the ground, it's waiting for more to come around." Or in the case of rain, "if it starts before seven, it will quite before eleven." Or "mackerel skies and mare's tails, make wise sailors set short sails." Incidentally, you'll find a lot of this sort of stuff in old Will Shakespeare, who seemed to know a lot about everything.