You would be hard pressed to find any thermocline in KY or Barkley, just too much current drawn thru them. KY Lake has a defined main and secondary channel that are both marked by buoys. Get a map or use a GPS map like a Navionics to run the deep edges of either of these channels. Just be prepared to lose a bunch of baits since most all the channel drops are crooked , have several depth changes,and have lots of stumps and man-made structure along them. You might find some crappie along the deepest flats in front of the dam.