And in Pennsylvania in January, it doesn't take much extra flow to make things too cold. You mention 180-195 in the city with a 160, that doesn't happen with the outside temp is 0F.
It's a whole different world up here, I drove around (in the city) in my previous car for a while with blankets on when the thermostat went bad.
Black Lady 2001, from what you describe, it's possible you have another problem beyond the thermostat, but you definitely have a problem there (or the temp sensor, as mentioned).